EA041617B1 - 2,5-DISUBSTITUTED 3-METHYLPYRAZINES AND 2,5,6-TRI-SUBSTITUTED 3-METHYLPYRAZINES AS SHP2 ALLOSTERIC INHIBITORS - Google Patents

Description

Cross-reference to related applications

This application claims priority over U.S. Provisional Application No. 62/361,249, filed July 12, 2016, and U.S. Provisional Application No. 62/449,523, filed January 23, 2017, the contents of which are incorporated herein by reference in in all its fullness.

Field of invention

The present invention relates to SHP2 protein tyrosine phosphatase inhibitors useful in the treatment of diseases or disorders. In particular, the present invention relates to compounds and compositions that inhibit SHP2, methods for treating diseases associated with SHP2, and methods for synthesizing such compounds.

Background of the invention

Protein tyrosine phosphatase-2 (SHP2), containing a BN2 domain, is a non-receptor protein tyrosine phosphatase encoded by the PTPN1 1 gene that is involved in many cellular functions, including proliferation, differentiation, cell cycle maintenance, and migration. SHP2 is involved in signal transduction via Ras-mitogen-activated protein kinase, JAK-STAT, or phosphoinositol-3-kinase-AKT signaling pathways.

SHP2 contains two N-terminal type 2 Src homologous domains (N-SH2 and C-SH2), a catalytic domain (PTP) and a C-terminal tail. Two BN2 domains control the intracellular location and regulation of SHP2 functions. The molecule is in an inactive, self-inhibited conformation, stabilized by a bond system formed by residues of both N-SH2 and PTP domains. Stimulation, for example, by cytokines or growth factors leads to the opening of the catalytic site, resulting in enzymatic activation of SHP2.

Mutations in the PTPN1 1 gene, and consequently in SHP2, have been identified in several human diseases such as Noonan syndrome, Leopard syndrome, juvenile myelomonocytic leukemia, neuroblastoma, melanoma, acute myeloid leukemia, and cancers of the breast, lung, and rectum. Therefore, SHP2 is a very promising target for the development of new treatments for various diseases. The compounds of the present invention fulfill the need for small molecules that inhibit SHP2 activity.

Brief description of the invention

The present invention relates to compounds capable of inhibiting SHP2 activity. The present invention also provides a method for preparing the compounds disclosed herein, pharmaceutical formulations containing such compounds, and methods for using such compounds and compositions to control diseases or disorders associated with disruption of SHP2 activity.

One aspect of the present invention relates to compounds of formula I-W

^R4

I-W or its pharmaceutically acceptable salts or stereoisomers, where:

A represents heterocycloalkyl, aryl or heteroaryl, while heterocycloalkyl, aryl and heteroaryl are 5-12-membered monocyclic or 5-12-membered polycyclic, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from the group consisting of N, S, P and O;

Y ¹ is -S-, direct bond, -NH-, -S(O) ₂ -, S(O) ₂ -NH- or -C(=CH ₂ )-;

Y ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ;

R ¹ is independently at each occurrence -H, -Q-Cg-alkyl, -OR ⁶ , halogen, -CN, -NR ⁵ R ⁶ , -S(O)2R ⁵ , -C(O)NR ⁵ R ⁶ , NR ⁵ C(O)R ⁶ , monocyclic or polycyclic heterocyclyl, spiroheterocyclyl, heteroaryl or oxo, wherein each alkyl, heterocyclyl, spiroheterocyclyl or heteroaryl is optionally substituted with one or more of -OH, -CN or -S(O)2R ⁵ , where heterocyclyl contains 15 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and spiroheterocycle contains one or more heteroatoms selected from from N, S, P and O;

R ² is independently -OH, -CN, -Ci-Cg-alkyl, -C ₂ -C6-alkenyl or -C3-C3-cycloalkyl; wherein each alkyl, alkenyl, cycloalkyl is optionally substituted with one or more of —OH or halogen;

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R ^a is independently at each occurrence -H;

R ^b is independently in each occurrence -H, -C1-C6-alkyl, -C3-C8-cycloalkyl or heterocyclyl, wherein heterocyclyl is 5-12 membered monocyclic or 5-12 membered polycyclic containing 1-5 heteroatoms, selected from the group consisting of N, S, P and O; wherein each alkyl, cycloalkyl, or heterocycle is optionally substituted with one or more of -NR5R ⁶ , (CH2) _n OH, or -CF3;

R ³ is independently -C1-C6-alkyl, 3-12 membered polycyclic heterocycle, 5-12 membered spiro-heterocycle, C3-C8-cycloαalkyl, or -(CH2)nR ^b , wherein each alkyl, spiro-heterocycle, heterocycle or cycloalkyl is optionally substituted one or more of -C1-C ₆ -alkyl, -NH2, heterocyclyl or spiroheterocyclyl, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiroheterocycle contains one or more heteroatoms selected from N, S, P and O; or

R ³ can be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, with each heterocycle or spiro heterocycle optionally substituted with one or more of -C1-C6 alkyl, halogen, -OR ^b , -NH2, -NHR ^b , heteroaryl, heterocyclyl, -(CH2) _n NH ₂ , -(CH ₂ ) _n OH, -CONHR ^b or =O, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and spiro heterocycle contains one or more heteroatoms selected from N, S, P and O;

R ⁴ is independently -H, -C ₁ -C ₆ -alkyl, -C ₁ -C ₆ -hydroxyalkyl, -C(O)OR ⁵ , NH(CH2)nOH, -C(O)NH (CH2)nOH , -C(O)R ^b , -NH2, -OH, -CN or -C(O)NR5R ⁶ , each alkyl being optionally substituted with one or more of -OH or -OR ^b ; or

R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, where the heterocycle is optionally substituted with oxo, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N , S, P and O;

R ⁵ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁶ is independently -H, -C1-C6 alkyl, -C3-C8 cycloalkyl, monocyclic 3-12 membered heterocycle, -OR ⁷ or -CF3, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N , S, P and O;

R ⁷ and R ⁸ are independently at each occurrence -H; and n is independently at each occurrence 0, 1, 2, 3, 4, 5, or 6.

Another aspect of the present invention relates to compounds of formula I

^R2

R ⁴ I or its pharmaceutically acceptable salts or stereoisomers, where:

A is a 5-12-membered monocyclic or polycyclic heterocycloalkyl, aryl or heteroaryl, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O;

Y ¹ is -S- or a direct link;

Y ² is -NR ^a -;

R ¹ is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -OH, halogen, -CN, -NR5R ⁶ or -S(O)R ⁵ ;

R ² is independently -OH, -CN, -Cl-C ₆ alkyl ₎ -C 2 -C ₆ -alkenyl or -C ₃ -C ₈ -cycloalkyl; wherein each alkyl, alkenyl or cycloalkyl is optionally substituted with one or more of —OH or halogen;

R ^a is independently at each occurrence -H;

R ^b is independently in each occurrence -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl or heterocyclyl containing 1-5 heteroatoms selected from the group consisting of N, S, P and O ; wherein each alkyl, cycloalkyl or heterocycle is optionally substituted with one or more of —OH or NR5R ⁶ ;

R ³ is independently -C ₁ -C ₆ -alkyl or 3-12-membered polycyclic heterocycle, each alkyl or heterocycle is optionally substituted with one or more -NH ₂ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of from N, S, P and O; or

R ³ may be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, each heterocycle or spiro heterocycle being optionally substituted with -Ci-C6-alkyl, -OH, or NH ₂ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from H, S, P and O;

R ⁴ is independently -H, or -Ci-C6-alkyl, with each alkyl optionally substituted with one or more -OH; or

R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, wherein the heterocycle is optionally substituted with oxo, wherein the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁵ is independently -H, -Ci-C6-alkyl, -C3-C3-cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, R and O;

R ⁶ is independently -H, -Ci-Ce-alkyl, -C3-C3-cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, R and O;

R ⁷ and R ⁸ are independently at each occurrence -H; and η is independently at each occurrence 0, 1.2, 3, 4, 5, or 6.

Another aspect of the present invention relates to compounds of formula I-W6

or its pharmaceutically acceptable salts or stereoisomers, where:

A is a 5-12-membered monocyclic or polycyclic heteroaryl;

Υ ¹ represents -S-;

Υ ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ;

R ³ is combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, with each heterocycle or spiro heterocycle optionally substituted with one or more of -Ci-Ce-alkyl, -OH, -NH ₂ , heteroaryl, heterocyclyl, -(CH ₂ ) _n NH ₂ or -CONHR ^b ;

R ¹ is independently at each occurrence -H, -Ci-Ce-alkyl, -OH, halogen, -CN or -NR ⁵ R ⁶ ;

R ² is -Ci-Ce-alkyl;

R ^b is independently at each occurrence -H or -C1-C ₆ -alkyl;

R ⁴ is -H, -C1-C ₆ -alkyl, -C1-C ₆ -hydroxyalkyl, -C(O)NH(CH ₂ ) _n OH, -C(O)R ^b , -C(O)NR ⁵ R ⁶ , -OH or -CN, with alkyl optionally substituted with one or more -OH; or each R ⁵ and R ⁶ independently at each occurrence are -H or -Ci-C6-alkyl; and η is independently at each occurrence 1, 2, 3, 4, 5, or 6.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which Υ ¹ represents -S-.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which Υ ¹ is a direct bond, -ΝΗ-, Υ ¹ is -S(O) ₂ -, -S(O) ₂ NH- or - C (= CH) ₂ -.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which Y ² represents -(NR ^a )-.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which R ³ represents -Ci-Cg-alkyl, which is optionally substituted by one or more of -NH ₂ , heterocyclyl or spiroheterocyclyl.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which R ³ and R ^a together with the atoms to which they are attached, are combined to form a 5-12-membered spiroheterocycle, which is optionally substituted with -C1- _C6 - alkyl, -OH or -NH ₂ .

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which the 5-12-membered spiro heterocycle contains piperidinyl.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which the 5-12-membered spiro heterocycle contains oxygen.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 3-12-membered monocyclic heterocycle, which is optionally substituted

-C ₁ -C ₆ -alkyl, -OH, -NH ₂ , heteroaryl, heterocyclyl, -(CH ₂ )nNH ₂ or -CONHRb.

In a particular embodiment, the invention relates to compounds or their pharmaceutically acceptable salts or stereoisomers, in which R ^a and R ⁴ together with the atom to which they are attached, are combined to form a polycyclic 3-12-membered heterocycle.

In a particular embodiment, the invention relates to compounds or pharmaceutically acceptable salts or stereoisomers thereof, wherein R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 3-12 membered polycyclic heterocycle which is optionally substituted with -NH2.

In a particular embodiment, the invention relates to compounds or pharmaceutically acceptable salts or stereoisomers thereof, wherein A is heterocycloalkyl or aryl.

In a particular embodiment, the invention relates to compounds or pharmaceutically acceptable salts or stereoisomers thereof, wherein e A is heteroaryl.

Another aspect of the present invention relates to compounds or their pharmaceutically acceptable salts, or stereoisomers, which are selected from the group consisting of:

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Another aspect of the present invention relates to compounds or their pharmaceutically acceptable salts, or stereoisomers, which are selected from the group consisting of:

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Another aspect of the present invention relates to compounds or their pharmaceutically acceptable salts, or stereoisomers, which are selected from the group consisting of:

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Another aspect of the present invention relates to compounds or their pharmaceutically acceptable salts, or stereoisomers, which are selected from the group consisting of:

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him or

Yet another aspect of the present invention relates to an earth salt compound, or stereoisomer, which is pharmaceutically at CI

/ (A170).

Yet another aspect of the present invention relates to an acceptable salt compound, or stereoisomer, which is or is a pharmaceutically acceptable

Another aspect of the present invention relates to an acceptable salt compound, or stereoisomer, which is or is pharmaceutically acceptable.

Another aspect of the present invention relates to a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, which is

Another aspect of the present invention relates to a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, which is

Another aspect of the present invention relates to methods of treating a disease associated with SHP2 modulation in a subject in need thereof, which comprises administering to the subject an effective amount of one or more of the compounds disclosed herein (for example, compounds of formula I, I-W and I-W6 and their pharmaceutically acceptable salts or stereoisomers).

Another aspect of the present invention is directed to pharmaceutical compositions containing one or more of the compounds disclosed herein (for example, compounds of formula I, I-W and I-W6 and their pharmaceutically acceptable salts or stereoisomers), and a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier may further contain an excipient, diluent or surfactant. The pharmaceutical composition may be effective in treating a disease associated with SHP2 modulation in a subject in need thereof.

Another aspect of the present invention relates to methods of treating a disease associated with SHP2 modulation in a subject in need thereof, comprising administering to the subject an effective amount of a pharmaceutical composition containing one or more of the compounds disclosed herein (for example, compounds of formula compounds of formula I, I-W and I-W6 and their pharmaceutically acceptable salts or stereoisomers).

The present invention also provides compounds and pharmaceutical compositions that are useful in the inhibition of SHP2.

Detailed description of the invention

In a first aspect, compounds of formula I are described.

where A, R ¹ , R ² , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above. In another aspect, compounds of formula II are described.

R ² (R ¹ ),

^.R3

^R4

II f where A, R ¹ , R ² , R ³ , R ⁴ , Y ² and n are as described above. In yet another aspect, compounds of formula III are described.

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(R ¹ ,R ³

^R4

III where A, R ¹ , R ² , R ³ , R ⁴ , Y ² and n are as described above.

One aspect of the present invention relates to compounds of formula I-V1

where A, R ¹ , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above.

One aspect of the present invention relates to compounds of formula I-V2

where A, R ¹ , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above.

One aspect of the present invention relates to compounds of formula I-W

where A, R ¹ , R ² , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above.

One aspect of the present invention relates to compounds of formula I

where A, R ¹ , R ² , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above.

One aspect of the present invention relates to compounds of formula I-W6

where A, R ¹ , R ² , R ³ , R ⁴ , Y ¹ , Y ² and n are as described above.

Details of the present invention are set forth in the accompanying description below. Although methods and materials similar or equivalent to those described herein may be used in the practice or testing of the present invention, illustrative methods and materials are described below. Other features, objects and advantages of the present invention will become apparent from the description and from the claims. In the description and the appended claims, the singular forms also include the plural forms, unless the context clearly indicates otherwise. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as generally understood by a person skilled in the art to which the present invention pertains. All patents and publications mentioned in this specification are incorporated herein by reference in their entirety.

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Each embodiment described herein may be used alone or in combination with any one or more other embodiments.

Definitions.

As used herein, the singular forms refer to one or more (ie, at least one) grammatical entities. For example, element means one element or more than one element.

The term and/or is used in this disclosure to mean either and or or, unless otherwise indicated.

By optional or optional, it is meant that the event or circumstance described below may or may not occur, and that the description includes cases where the event or circumstance occurs and cases where it does not. For example, optionally substituted aryl encompasses both aryl and substituted aryl as defined herein. With respect to any group containing one or more substituents, one of ordinary skill in the art will appreciate that such groups are not intended to introduce any substitution or substitution patterns that are sterically impractical, impossible to synthesize, and/or inherently unstable. nature.

The term optionally substituted is intended to mean that a particular chemical moiety (eg, an alkyl group) may (but need not) be bonded to other substituents (eg, heteroatoms). For example, an alkyl group that is optionally substituted may be a fully saturated alkyl chain (ie, a pure hydrocarbon). Alternatively, the same optionally substituted alkyl group may contain substituents other than hydrogen. For example, at any point in the chain, it may be linked to a halogen atom, a hydroxyl group, or any other substituent described herein. Thus, the term optionally substituted means that a particular chemical moiety may contain other functional groups, but does not necessarily contain any additional functional groups.

The term aryl refers to cyclic, aromatic hydrocarbon groups that contain 1 to 2 aromatic rings, including monocyclic or bicyclic groups such as phenyl, biphenyl or naphthyl. If the group contains two aromatic rings (bicyclic, etc.), then the aromatic rings of the aryl group can be connected at one point (for example, biphenyl) or fused (for example, naphthyl). The aryl group may optionally be substituted with one or more substituents, eg 1-5 substituents, at any attachment point. Illustrative substituents include, but are not limited to -H, halogen, -OC ₁ -C ₆ alkyl, -C ₁ -C6 alkyl, -OC ₂ -C6 alkenyl, -OC ₂ -C6 alkynyl, -C ₂ -C6 alkenyl , -C ₂ -C6-alkynyl, -OH, -OR (O) (OH) ₂ , -OC (O) C ₁ -C ₆ alkyl, -C (O) C ₁ -C ₆ -alkyl, -OC ( O) OC ₁ -C ₆ -alkyl, -NH2, -NH (C ₁ -C ₆ -alkyl), -N (C ₁ -C ₆ -alkyl) ₂ , -S (O) ₂ -C ₁ -C ₆ alkyl, -S(O)NHC ₁ -C ₆ -alkyl and -S(O)N(C ₁ -C ₆ -alkyl) ₂ . The substituents themselves may optionally be substituted.

Unless specifically defined otherwise, the term heteroaryl means a monovalent or multivalent monocyclic aromatic radical or polycyclic aromatic radical with 5-24 ring atoms containing one or more heteroatoms in the ring selected from N, S, P and O, with the remaining atoms in rings are C. Heteroaryl, as defined herein, also means a bicyclic heteroaromatic group, where the heteroatom is selected from N, S, P, and O. The aromatic radical is optionally independently substituted with one or more substituents described herein. Examples include, without limitation, furyl, thienyl, pyrrolyl, pyridyl, pyrazolyl, pyrimidinyl, imidazolyl, isoxazolyl, oxazolyl, oxadiazolyl, pyrazinyl, indolyl, thiophen-2-yl, quinolyl, benzopyranyl, isothiazolyl, thiazolyl, thiadiazolyl, benzo[d]imidazolyl, thieno[3,2-b]thiophene, triazolyl, triazinyl, imidazo[1,2-b]pyrazolyl, Furo[2,3-c]pyridinyl, imidazo[1,2a]pyridinyl, indazolyl, 1-methyl-1H- indazolyl, pyrrolo[2,3-c]pyridinyl, pyrrolo[3,2-N-pyridinyl, pyrazolo[3,4-c]pyridinyl, thieno[3,2-c]pyridinyl, thieno[2,3-c]pyridinyl , thieno[2,3-b]pyridinyl, benzothiazolyl, indolyl, indolinyl, indolinonyl, dihydrobenzothiophenyl, dihydrobenzofuranyl, benzofuran, chromanyl, thiochromanyl, tetrahydroquinolinyl, dihydrobenzothiazine, dihydrobenzoxanyl, quinolinyl, isoquinolinyl, 1,6-naphthyridinyl, benzo[de]isoquinolinyl , pyrido[4,3-b][1,6]naphthyridinyl, thieno[2,3-b]pyrazinyl, quinazolinyl, tetrazolo[1,5-a]pyridinyl, [1,2,4]triazolo[4,3 -a]pyridinyl, isoindolyl, isoindolin-1-one, indolin-2-one, pyrrolo[2,3-b]pyridinyl, pyrrolo [3,44e]pyridinyl, pyrrolo[3,2b]pyridinyl, imidazo[5,4-b]pyridinyl, pyrrolo[1,2-a]pyrimidinyl, tetrahydropyrrole[1,2a]pyrimidinyl, 3,4-dihydro-2H -1λ ² -pyrrolo[2,1-b]pyrimidine, dibenzo[b,d]thiophene, pyridin-2-one, furo[3,2-c]pyridinyl, furo[2,3-c]pyridinyl, 1H- pyrido[3,4-][1,4]thiazinyl, 2-methylbenzo[d]oxazolyl, 1,2,3,4-tetrahydropyrrolo[1,2-a]pyrimidyl, 2,3-dihydrobenzofuranyl, benzoxazolyl, benzisoxazolyl, benzo[d]isoxazolyl, benzo[d]oxazolyl, furo[2,34e]pyridinyl, benzothiophenyl, 1,5-naphthyridinyl, FuRo[3,2-b]pyridinyl, [1,2,4]triazolo[1,5 -a]pyridinyl, benzo[1,2,3]triazolyl, 1-methyl-1Hbenzo[d][1,2,3]triazolyl, imidazo[1,2-a]pyrimidinyl, [1,2,4]triazolo [4,3-b]pyridazinyl, quinoxalinyl, benzo[c] [1,2,5]thiadiazolyl, benzo[c] [1,2,5]oxadiazolyl, 1,3-dihydro-2H-benzo[d]imidazole -2-he,

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3,4-dihydro-2H-pyrazolo[1,5-b][1,2]oxazinyl, 3,4-dihydro-2H-benzo[b][1,4]oxazinyl, 4,5,6,7tetrahydropyrazolo[ 1,5-a]pyridinyl, thiazolo[5,4-d]thiazolyl, imidαzo[2,1-b][1,3,4]thiαdiazolyl, thieno[2,3-b]pyrrolyl, 3H-indolyl, benzo [d][1,3]dioxolyl, pyrazolo[1,5-a]pyridinyl and their derivatives.

Alkyl refers to a straight or branched chain saturated hydrocarbon. C1-C6 alkyl groups contain from 1 to 6 carbon atoms. Examples of the C ₁ -C ₆ alkyl group include, without limitation, methyl, ethyl, propyl, butyl, pentyl, isopropyl, isobutyl, sec-butyl and tert-butyl, isopentyl and neopentyl.

The term alkenyl means an aliphatic hydrocarbon group containing a carbon-carbon double bond, and which may be straight or branched, while containing from about 2 to about 6 carbon atoms in the chain. Some alkenyl groups contain from 2 to about 4 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl or propyl are attached to the linear alkenyl chain. Illustrative alkenyl groups include ethenyl, propenyl, n-butenyl, and iso-butenyl. A C2-C6 alkenyl group is an alkenyl group containing 2 to 6 carbon atoms.

The term alkynyl means an aliphatic hydrocarbon group containing a carbon-carbon triple bond, and which may be straight or branched, while containing from about 2 to about 6 carbon atoms in the chain. Some alkynyl groups contain from 2 to about 4 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl or propyl are attached to the linear alkynyl chain. Illustrative alkynyl groups include ethynyl, propynyl, n-butynyl, 2-butynyl, 3-methylbutynyl, and n-pentynyl. C ₂ -C ₆ alkynyl group is an alkynyl group containing 2 to 6 carbon atoms.

The term cycloalkyl means monocyclic or polycyclic saturated carbon rings containing 3-18 carbon atoms. Examples of cycloalkyl groups include, without limitation, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptanyl, cyclooctanyl, norboranyl, norborenyl, bicyclo[2.2.2]octanyl, or bicyclo[2.2.2]octenyl. C ₃ -C ₈ -cycloalkyl is a cycloalkyl group containing from 3 to 8 carbon atoms. The cycloalkyl group may be fused (eg decalin) or internally bridged (eg norbornane).

The term cycloalkenyl means monocyclic, non-aromatic, unsaturated carbon rings containing 4-18 carbon atoms. Examples of cycloalkenyl groups include, without limitation, cyclopentenyl, cyclohexenyl, cycloheptenyl, cyclooctenyl, and norborenyl. C ₄ -C ₈ -cycloalkenyl is a cycloalkenyl group containing from 4 to 8 carbon atoms.

In some embodiments, the terms heterocyclyl, or heterocycloalkyl, or heterocycle refer to monocyclic or polycyclic 3-24 membered rings containing carbon atoms and heteroatoms selected from oxygen, phosphorus, nitrogen, and sulfur, and no carbon atoms or heteroatoms of the ring common delocalized π-electrons (aromatics). Heterocyclyl rings include, without limitation, oxetanyl, azetidinyl, tetrahydrofuranyl, pyrrolidinyl, oxazolinyl, oxazolidinyl, thiazolinyl, thiazolidinyl, pyranyl, thiopyranyl, tetrahydropyranyl, dioxalinyl, piperidinyl, morpholinyl, thiomorpholinyl, thiomorpholinyl-s-oxide, thiomorpholinyl-s , diazepinil, tropanil and homotropanil. The heterocyclyl or heterocycloalkyl ring may also be fused or internally bridged, for example may be a bicyclic ring.

In some embodiments, a heterocyclyl or heterocycloalkyl or heterocycle is a saturated, partially saturated, or unsaturated, mono- or bicyclic ring containing 3-24 atoms, of which at least one atom is selected from nitrogen, sulfur, or oxygen, which, if not otherwise specified, may be bonded at a carbon or nitrogen atom, wherein the -CH ₂ - group may optionally be replaced by -C(O)-, or the sulfur atom in the ring may be optionally oxidized to form S-oxides. A heterocyclyl may be a saturated, partially saturated or unsaturated, mono- or bicyclic ring containing 5 or 6 atoms, of which at least one atom is selected from nitrogen, sulfur or oxygen, which, unless otherwise indicated, may be atom-linked carbon or nitrogen, while the group -CH ₂ - may be optionally replaced by -C(O)-, or the sulfur atom in the ring may be optionally oxidized to form S-oxide(s). Non-limiting examples and suitable meanings of the term heterocyclyl are thiazolidinyl, pyrrolidinyl, pyrrolinyl, 2-pyrrolidonyl, 2,5dioxopyrrolidinyl, 2-benzoxazolinonyl, 1,1-dioxotetrahydrothienyl, 2,4-dioxoimidazolidinyl, 2oxo-1,3,4-(4- triazolinyl), 2-oxazolidinonyl, 5,6-dihydrouracilyl, 1,3-benzodioxolyl, 1,2,4oxadiazolyl, 2-azabicyclo[2.2.1]heptyl, 4-thiazolidonyl, morpholino, 2-oxotetrahydrofuranyl, tetrahydrofuranyl, 2,3 -dihydrobenzofuranyl, benzothienyl, tetrahydropyranyl, piperidyl, 1-oxo-1,3dihydroisoindolyl, piperazinyl, thiomorpholino, 1,1-dioxothiomorpholino, tetrahydropyranyl, 1,3dioxolanyl, homopiperazinyl, thienyl, isoxazolyl, imidazolyl, pyrrolyl, thiadiazolyl, isothiazolyl, 1,2 ,4-triazolyl, 1,3,4-triazolyl, pyranyl, indolyl, pyrimidyl, thiazolyl, pyrazinyl, pyridazinyl, pyridyl, 4-pyridonyl, quinolyl and 1-isoquinolonyl.

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As used herein, the term halogen or halide means a fluoro, chloro, bromo, iodo group.

The term carbonyl refers to a functional group containing a carbon atom connected to an oxygen atom through a double bond. In this document, it may be abbreviated as oxo, C(O) or C=O.

Spirocycle or spirocyclic means bicyclic ring systems based on carbon atoms in which both rings are connected via a single atom. The rings may be different in size and nature, or be identical in size and nature. Examples include spiropentane, spirohexane, spiroheptane, spirooctane, spirononane, or spirodecan. One or both rings in a spirocycle may be fused to another carbocyclic, heterocyclic, aromatic, or heteroaromatic ring. One or more carbon atoms in the spirocycle may be replaced by a heteroatom (eg O, N, S or P). C ₅ -C ₁₂ -spirocycle is a spirocycle containing from 5 to 12 carbon atoms. One or more carbon atoms may be replaced by a heteroatom.

The term spirocyclic heterocycle, spiroheterocyclyl, or spiroheterocycle is intended to mean a spirocycle where at least one of the rings is a heterocycle (eg, at least one of the rings is furanyl, morpholinyl, or piperadinyl). The spirocyclic heterocycle may contain from 5 to 12 atoms, at least one of which is a heteroatom selected from N, O, S, and P.

The present invention also includes pharmaceutical compositions containing an effective amount of one or more of the disclosed compounds and a pharmaceutically acceptable carrier. As used herein, a pharmaceutically acceptable carrier, diluent, or excipient includes, without limitation, any adjuvant, carrier, excipient, glidant, sweetener, diluent, preservative, colorant/colorant, flavor enhancer, surfactant, a wetting agent, dispersing agent, suspending agent, stabilizer, isotonic agent, solvent, surfactant, or emulsifier approved by the United States Food and Drug Administration as acceptable for human or pet consumption.

The present invention includes pharmaceutically acceptable salts of the compounds described herein. Exemplary pharmaceutically acceptable salts include, without limitation, for example, water-soluble and water-insoluble salts such as acetate, amsonate (4,4-diaminostilbene-2,2-disulfonate), benzenesulfonate, benzoate, bicarbonate, bisulfate, bitartrate, borate, bromide, butyrate, calcium salt , calcium edetate, camsylate, carbonate, chloride, citrate, clavularate, dihydrochloride, edetate, edisylate, estolate, esilate, fiunarate, gluceptate, gluconate, glutamate, glycolylarsanilate, hexafluorophosphate, hexylresorcinate, hydrabamine, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, setionate, lactate, lactobionate, laurate, magnesium salt, malate, maleate, mandelate, mesylate, methyl bromide, methyl nitrate, methyl sulfate, mucat, napsilate, nitrate, N-methylglucamine ammonium salt, 3-hydroxy-2-naphthoate, oleate, oxalate, palmitate, pamoate (1,1-methene-bis-2-hydroxy-3-naphthoate, einbonate), pantothenate, phosphate/diphosphate, picrate, polygalacturonate, propionate, p-toluenesulfonate, salicylate, stearate, subacetate, succinate, sulfate, subsalicylate, su ramate, tannate, tartrate, theoclate, tosylate, triethiodide and valerate.

The term pharmaceutically acceptable salt also includes both acid addition salts and base addition salts. The term pharmaceutically acceptable acid addition salt refers to those salts which retain the biological efficacy and properties of the free bases, which are not biologically or otherwise undesirable, and which are formed with inorganic acids such as, but not limited to, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and the like, and organic acids such as, but not limited to, acetic acid, 2,2-dichloroacetic acid, adipic acid, alginic acid, ascorbic acid, aspartic acid, benzenesulfonic acid, benzoic acid, 4 - acetamidobenzoic acid, camphoric acid, camphor-10-sulfonic acid, capric acid, caproic acid, caprylic acid, carbonic acid, cinnamic acid, citric acid, cyclamic acid, dodecylsulfuric acid, ethane-1,2-disulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, formic oic acid, fumaric acid, galactaric acid, gentisic acid, glucoheptonic acid, gluconic acid, glucuronic acid, glutamic acid, glutaric acid, 2-oxo-glutaric acid, glycerophosphoric acid, glycolic acid, hippuric acid, isobutyric acid, lactic acid, lactobionic acid acid, lauric acid, maleic acid, malic acid, malonic acid, mandelic acid, methanesulfonic acid, mucic acid, naphthalene-1,5-disulfonic acid, naphthalene-2-sulfonic acid, 1-hydroxy-2-naphthoic acid, nicotinic acid, oleic acid, orotic acid, oxalic acid, palmitic acid, pamic acid, propionic acid, pyroglutamic acid, pyruvic acid, salicylic acid, 4-aminosalicylic acid, sebacic acid, stearic acid, succinic acid, tartaric acid, thiocyanic acid, ptoluenesulfonic acid, trifluoroacetic acid acid, undecylenic acid, and the like.

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The term pharmaceutically acceptable base addition salt refers to those salts that retain the biological efficacy and free acid properties that are not biologically or otherwise undesirable. Such salts are obtained by adding an inorganic base or an organic base to a free acid. Salts derived from inorganic bases include, without limitation, sodium, potassium, lithium, ammonium, calcium, magnesium, iron, zinc, copper, manganese, aluminum salts, and the like. For example, inorganic salts include, without limitation, the ammonium, sodium, potassium, calcium, and magnesium salts. Salts derived from organic bases include, but are not limited to, salts of primary, secondary, and tertiary amines, substituted amines, including naturally occurring substituted amines, cyclic amines, and basic ion exchange resins such as ammonia, isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine , diethanolamine, ethanolamine, dinol, 2-dimethylaminoethanol, 2-diethylaminoethanol, dicyclohexylamine, lysine, arginine, histidine, caffeine, procaine, hydrabamine, choline, betaine, benetamine, benzathine, ethylenediamine, glucosamine, methylglucamine, theobromine, triethanolamine, tromethamine, purines , piperazine, piperidine, N-ethylpiperidine, polyamine resins, and the like.

The term tautomers refers to a range of compounds that have the same number and type of atoms, but differ in their ability to form bonds and are in equilibrium with each other. The tautomer is a separate representative of this series of compounds. Typically, a single tautomer is depicted, but it should be understood that this single structure is intended to represent all possible tautomers that may exist. Examples include keto-enol tautomerism. Where a ketone is depicted, it should be understood that both the enol and ketone forms are part of the present invention.

The term stereoisomers refers to a series of compounds that are characterized by the same number and type of atoms and have the same ability to form bonds between these atoms, but differ in three-dimensional structure. The term stereoisomer refers to any member of a given series of compounds. For example, a stereoisomer may be an enantiomer or a diastereomer. The present invention includes stereoisomers of the compounds described herein.

The term effective amount, when used with respect to a compound, is an amount effective to treat or prevent a disease in a subject, as described herein.

As used herein, the term carrier encompasses carriers, excipients, and diluents and means a material, composition, or carrier medium, such as a liquid or solid excipient, diluent, excipient, solvent, or encapsulation material, involved in the transfer or transportation of a pharmaceutical agent from one organ or body part to another organ or body part of the subject. The term treatment in relation to a subject refers to the normalization of at least one symptom of a disorder present in the subject. Treatment includes elimination, normalization, or at least partial reduction in the intensity of the disorder.

The term prevent or warning in relation to a subject refers to preventing the subject from being affected by a disease or disorder. Prevention includes prophylactic treatment. For example, prevention may include administering to a subject one or more of the compounds disclosed herein before the subject is affected by the disease, wherein the administration will prevent the subject from being affected by the disease.

The term disorder is used herein to refer to a disease, condition, or disease and is used interchangeably with these terms unless otherwise noted.

As used herein, the term administer, administer, or administer refers either to the direct administration to a subject of one or more of the disclosed compounds, or a pharmaceutically acceptable salt of one or more of the disclosed compounds, or to a composition containing one or more of the disclosed compounds, or to the administration to a subject of a prodrug that is a derivative or analogue of a compound, or a pharmaceutically acceptable salt of a compound, or composition, which can produce an equivalent amount of the active compound in the subject's body.

The patient or subject is a mammal, such as a human, mouse, rat, guinea pig, dog, cat, horse, cow, pig, or non-human primate such as a monkey, chimpanzee, baboon, or rhesus.

Compounds of the present invention.

In one or more embodiments of the invention, the compound is represented by the formula I-W

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^R4

I-W

G or its pharmaceutically acceptable salt or stereoisomer, where:

A represents heterocycloalkyl, aryl or heteroaryl, while heterocycloalkyl, aryl and heteroaryl are 5-12-membered monocyclic or 5-12-membered polycyclic, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from the group consisting of N, S, P and O;

Y ¹ is -S-, direct bond, -NH-, -S(O) ₂ -, S(O) ₂ -NH- or -C(=CH ₂ )-;

Y ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ;

R ¹ is independently at each occurrence -H, -C1-C6 alkyl, -OR ⁶ , halogen, -CN, -NR5R ⁶ , -S(O)2R ⁵ , -C(O)NR5R ⁶ , NR5C(O )R ⁶ , monocyclic or polycyclic heterocyclyl, spiroheterocyclyl, heteroaryl, or oxo, wherein each alkyl, heterocyclyl, spiroheterocyclyl, or heteroaryl is optionally substituted with one or more of -OH, -CN, or -S(O) ₂ R ⁵ , wherein the heterocyclyl contains 15 heteroatoms selected from the group consisting of N, S, P and O, and the heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from N, S, R and O;

R ² is independently -OH, -CN, -C ₁ -C ₆ -alkyl, -C ₂ -C ₆ -alkenyl or -C ₃ -C ₈ -cycloalkyl; wherein each alkyl, alkenyl, cycloalkyl is optionally substituted with one or more of —OH or halogen;

R ^a is independently at each occurrence -H;

R ^b represents independently in each case -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl or heterocyclyl, and heterocyclyl is 5-12-membered monocyclic or 5-12-membered polycyclic containing 1- 5 heteroatoms selected from the group consisting of N, S, P and O; wherein each alkyl, cycloalkyl, or heterocycle is optionally substituted with one or more of -NR5R ⁶ , -(CH2)nOH, or -CF3;

R ³ is independently -C1-C6-alkyl, 3-12-membered polycyclic heterocycle, 5-12-membered spiro-heterocycle, C3-C8-cycloalkyl or -(CH2)nR ^b , wherein each alkyl, spiro-heterocycle, heterocycle or cycloalkyl is optionally substituted one or more of -C1-C ₆ -alkyl, -NH2, heterocyclyl or spiroheterocyclyl, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiroheterocycle contains one or more heteroatoms selected from N, S, P and O; or

R ³ can be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, with each heterocycle or spiro heterocycle optionally substituted with one or more of -C1-C6 alkyl, halogen, -OR ^b , -NH2, -NHR ^b , heteroaryl, heterocyclyl, -(CH2) _n NH ₂ , -(CH ₂ ) _n OH, -CONHR ^b or =O, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and spiro heterocycle contains one or more heteroatoms selected from N, S, P and O;

R ⁴ is independently -H, -C1-C6-alkyl, -C1-C6-hydroxyalkyl, -C(O)OR ⁵ , -NH(CH2) _n OH, -C(O)NH (CH ₂ ) _n OH , -C(O)R ^b , -NH ₂ , -OH, -CN or -C(O)NR ⁵ R ⁶ , each alkyl being optionally substituted with one or more of -OH or -OR ^b ; or

R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, where the heterocycle is optionally substituted with oxo, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N , S, P and O;

R ⁵ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁶ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle, -OR ⁷ or -CF3, where the heterocycle contains 1-5 heteroatoms selected from the group , consisting of N, S, P and O;

R ⁷ and R ⁸ are independently at each occurrence -H; and n is independently at each occurrence 0, 1, 2, 3, 4, 5, or 6.

In one or more embodiments of the invention, the compound is represented by formula I

- 52 041617

or a pharmaceutically acceptable salt or stereoisomer thereof, wherein:

A is a 5-12-membered monocyclic or polycyclic heterocycloalkyl, aryl or heteroaryl, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O;

Y ¹ is -S- or a direct link;

Y ² is -NR ^a -;

R ¹ is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -OH, halogen, -CN, -NR5R ⁶ or -S(O)R ⁵ ;

R ² is independently -OH, -CN, -C ₁ -C ₆ -alkyl, -C ₂ -C ₆ -alkenul or -C3-C ₈ -cycloalkyl; wherein each alkyl, alkenyl or cycloalkyl is optionally substituted with one or more of —OH or halogen;

R ^a is independently at each occurrence -H;

R ^b is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -C3-C8-cycloalkyl or heterocyclyl containing 1-5 heteroatoms selected from the group consisting of N, S, P and O; wherein each alkyl, cycloalkyl or heterocycle is optionally substituted with one or more of —OH or —NR5R ⁶ ;

R ³ is independently -C ₁ -C ₆ -alkyl or a 3-12 membered polycyclic heterocycle, wherein each alkyl or heterocycle is optionally substituted with one or more -NH2, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O; or

R ³ may be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, each heterocycle or spiro heterocycle being optionally substituted with -C ₁ -C ₆ -alkyl, -OH or NH2, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from H, S, P and O;

R ⁴ is independently -H, or -C ₁ -C ₆ -alkyl, with each alkyl optionally substituted with one or more -OH; or

R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, wherein the heterocycle is optionally substituted with oxo, wherein the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁵ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁶ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O;

R ⁷ and R ⁸ are independently at each occurrence -H; and n is independently at each occurrence 0, 1, 2, 3, 4, 5, or 6.

In one or more embodiments of the invention, the compound is represented by formula I-W6

^R4

I-W6 or a pharmaceutically acceptable salt or stereoisomer thereof, wherein:

A is a 5-12-membered monocyclic or polycyclic heteroaryl;

Y ¹ is -S-;

Y ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ;

R ³ is combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, each heterocycle or spiro heterocycle being optionally substituted with one or more of -C ₁ -C ₆ -alkyl, -OH, -NH2, heteroaryl, heterocyclyl,

-(CH ₂ ) _n NH ₂ or -CONHRb;

R ¹ is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -OH, halogen, -CN or -NR5R ⁶ ;

R2 is -C ₁ -C ₆ alkyl;

R ^b is independently at each occurrence -H or -C ₁ -C ₆ -alkyl;

R ⁴ is -H, -C ₁ -C ₆ alkyl, -C ₁ -C ₆ hydroxyalkyl, -C(O)NH(CH2) _n OH, -C(O)R ^b , -C(O) NR5R ⁶ , -OH or -CN, wherein the alkyl is optionally substituted with one or more -OH; or each R ⁵ and R ⁶ independently at each occurrence are -H or -C ₁ -C ₆ -alkyl; and n is independently at each occurrence 1, 2, 3, 4, 5, or 6.

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ¹ is -S.

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ¹ is a direct bond, -NH-, Y ¹ is -S(O) ₂ -, -S(O) ₂ NH-, or -C (= CH) ₂ -.

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ² is -(NR ^a )-.

In one or more embodiments of the invention, a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ is -C ₁ -C ₆ alkyl which is optionally substituted with one or more of -NH ₂ , heterocyclyl, or spiroheterocyclyl.

In one or more embodiments of the invention, a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 5-12 membered spiro heterocycle which is optionally substituted with -C1C ₆ -alkyl , -OH or -NH2.

In one or more embodiments of the invention, a compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the 5-12 membered spiro heterocycle contains piperidinyl.

In one or more embodiments of the invention, a compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the 5-12 membered spiro heterocycle contains oxygen.

In one or more embodiments of the invention, a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 3-12 membered monocyclic heterocycle which is optionally substituted with -C ₁ - C ₆ -alkyl, -OH, -NH2, heteroaryl, heterocyclyl, -(CH2) _n NH2 or -CONHR ^b

In one or more embodiments of the invention, a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ^a and R ⁴ together with the atom to which they are attached are combined to form a polycyclic 3-12 membered heterocycle.

In one or more embodiments of the invention, a compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 3-12 membered polycyclic heterocycle which is optionally substituted with -NH ₂ .

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein A is heterocycloalkyl or aryl.

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein A is heteroaryl.

In one or more embodiments of the invention, the compound, or a pharmaceutically acceptable salt or stereoisomer thereof, is selected from:

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- 56 041617

- 57 041617

- 58 041617

- 59 041617

- 60 041617

- 61 041617

- 62 041617

- 63 041617

- 64 041617

- 65 041617

- 66 041617

- 67 041617

- 68 041617

- 69 041617

- 70 041617

A-135

A-136

A-137

A-138

A-139

A-140

A-141

-71 041617 and their pharmaceutically acceptable salts, prodrugs, solvates, hydrates, tautomers or isomers.

In one or more embodiments, a compound of the present invention (e.g., a compound of formula I, II, III, I-V1, I-V2, I-W, I-X, I-Y, or I-Z) may be selected from:

No. connections Structure A-142 o G} ci h ^u A-143 A-144 1 / l / '1 _l g A-145 J1 ' i L · A-146 ΎΊ . T U 2 ., i L- ... -

- 72 041617

- 73 041617

- 74 041617

- 75 041617

-76041617

- 77 041617

- 78 041617

- 79 041617

-80041617

-81 041617

- 82 041617

-83041617

- 84 041617

A-208 m l ΎΊ ‘। । G A-209 su.. ^X —< fl U 'I'J r. “ L.-/ A-210 Ά 1 rx . .. A-211 - Λύ K L ζ I s- UK A-212 . To / 4. .ί ... Ί I K. =- ·-' Ι__γ ' A-213 ί Cλ1.

- 85 041617

A-214 A-1 i- A-215 ' ^: I g „_ '. - A-216 He - La - J Oy A-217 ' L . - -: ¹ \ A-218 kXCx -~T/ -AND· A-219 CO.Λ

- 86 041617

A-220 €O. i '.-. ECx A-221 1 '^'Λϊ_ J'V A-222 - ^: J JI 1 - : ¹ '6' A-223 m l ΪIX-X<x> A-224 ΝΧλ,.Ι.. ^; T'Qj A-225

- 87 041617

A-226 λ1. '1 1' .i . ' ¹ L L...... A-227 ^: . · . A-228 ri. ^; r UI... I ΐ to. A-229 il 1 L./ A-230 .,1' XIA. 'i u .. ..

- 88 041617

A-231 P 1 ^: : Ί I . I Ϊ Γ A-232 (C i ⁷ rxx A-233 I S )...( A-234 ' .... .. ,. 1 1V '°- 'lZ A-235 1 f H . ^..J'A

- 89 041617

A-236 I - ^li . J 'r L_ . A-237 on I/' f” V~ .J A-238 •to J. i... j.. A-239 H x / A-240 to /V J

- 90 041617

- 91 041617

A-247 XU J ² 'Π ., .. T7 K A-248 αχ l ^j (2a ., A-249 •W 1 ^J aa .. ji xx ³ I / A-250 n X___/ χ'X/\v A-251 ' = .... ^J -Ъ' · A-252 a< j, xa,, ,, j Oa ^J L /

- 92 041617

A-253 i ii :. ^: ! I! '> . - ,., Jui A-254 Cl. A 1 / l ...Ϊ. .-, ,v A-255 VI I '·. I G ’ i . . τχχ. A-256 XIlX ., ,. X ^: : ( a ' ... . _{L z} A-257 ^£ O / X w th A-258 ., .s. A UI rx ,, , να IT)

- 93 041617

A-259 LI ³ > - ί Qy A-260 . 1 And Ί ί i J V L, - L... A-261 ,..,. J. a τ z,.. ,. ^r U A-262 ..,. ,=. Λ Q Ό..... X 7 T 1л ^Η: lV A-263 ίΥΛ,. , -σ A-264 . s I CXTX^ .. ί J ί :k --L/

- 94 041617

A-265 /\nfft □ -- .J A-266 .=. J. il Ό , ., T ^: ΪΪΧ A-267 H ,, i ^F i ί' X rv -' I / A-268 ..=, 1 O', Xi . % 4 % A-269 nV , .. T J CK A-270 ,, .=. .1 1Г ΐ ( d , ., Μ I L

- 95 041617

A-271 =. I. l. x 1.4 1!. 2 .... .... '7% A-272 __/ /.__ >- ^Z >, r/i A-273 .. - _s ,1 ! ^! 'J7.1. .- -g ¹⁷ - ® A-274 „ 3. J XX 71 .. „ X ^c ' IX XX ' “ ^μ l-7 A-275

- 96 041617

A-276 - . ...S J. Τι i? A-277 , . 1 ? '7 2 -i . ..G T 7 y' Ί.J, ' A-278 ...... _.. λ ¢2 Ό .. .. alu A-279 . 1 J ¹ Ί ^Ί Ϊ ! J La 1 V' A-280 ... 1 1 ' 11 W- ^r β A-281 . ₅ 1 H 1 Ί _t ^{f Ξ} J ί - < λ..............

- 97 041617

- 98 041617

A-287 > 1 t >. T. ' ^Γ 1 . ij . A-288 ... X CI 7.i. ... -c ακ Vw A-289 . ~ 1 ¹¹ Ί ^Ί i . \ ^Ξ and b+ A-290 . 1 YYY; . .. GOS. ... _{L y} -i A-291 me. ^Ν /οΛγ . "3 < -C with A-292 Me ¹ i ^{ь f} ϊ ^Ν . ci ^Ν Ν ^ΝΗ Ν ¹ 4' 1 Ί ^υ U _c * Ό'

- 99 041617

- 100 041617

- 101 041617

Methods for the synthesis of the disclosed compounds.

Compounds of the present invention can be obtained in various ways, including methods conventional in chemistry. Suitable synthesis methods are illustrated in the following schemes.

Compounds of any of the formulas described herein can be prepared by methods known in the art of organic synthesis, which are represented in part by the following synthesis schemes and examples. From the schemes described below, it is quite clear that protective groups for sensitive or reactive groups are used, if necessary, in accordance with the general principles or laws of chemistry. Protective group operations are performed according to standard organic synthesis methods (T.W. Greene and P.G.M. Wuts, Protective Groups in Organic Synthesis, third edition, Wiley, New York, 1999). Such groups are removed at an appropriate stage in the synthesis of the compound using methods that are obvious to those skilled in the art. The selection processes, as well as the conditions for carrying out the reactions and the order of their implementation, must correspond to the preparation of the compounds of the present invention.

A person skilled in the art will understand if a stereocenter is present in any of the compounds of the present invention. Accordingly, the present invention includes both possible stereoisomers (unless otherwise indicated in relation to synthesis) and includes not only racemic compounds, but also individual enantiomers and/or diastereomers. If the compound is to be obtained as a single enantiomer or diastereomer, it can be obtained by stereospecific synthesis or by resolution of the final product or any suitable intermediate. Separation of the final product, intermediate or starting material can be carried out by any suitable method known in the art. See, for example, Stereochemistry of Organic Compounds, E. L. Eliel, S. H. Wilen, and L. N. Mander (Wiley-interscience, 1994).

Getting connections.

The compounds described herein can be obtained from commercially available starting materials or synthesized using known methods of organic, inorganic and/or enzymatic synthesis.

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The compounds of the present invention can be prepared in a variety of ways well known to those skilled in the art of organic synthesis. By way of example, the compounds of the present invention can be synthesized using the methods described below, as well as synthetic methods known in the art of synthetic organic chemistry, or variants thereof known to those skilled in the art. Such methods include, without limitation, the methods described below.

Scheme 1. General synthesis of 2-amino-5-thioaryl-(or thioheteroaryl)-6-methylpyrazines.

The general synthesis of 2-amino-5-thioaryl-(or thioheteroaryl)-6-methylpyrazines is shown in Scheme 1. 2-Bromo-5-chloro-3-methylpyrazine can be coupled with substituted aryl- or heteroaryl-1-thiol in the presence of a copper catalyst (for example, CuI). The resulting thioether can then be coupled with a substituted primary or secondary amine to give 2-amino-5-thioaryl-(or thioheteroaryl)-6-methylpyrazine. Additional deprotection and/or functionalization steps may be required to obtain the final compound.

Scheme 2. General synthesis of 2-amino-5-aryl(or heteroaryl)-6-methylpyrazines.

The general synthesis of 2-amino-5-aryl(or heteroaryl)-6-methylpyrazines is shown in Scheme 2. 2-Bromo5-chloro-3-methylpyrazine can be coupled with a substituted aryl- or heteroarylboronic acid in the presence of a palladium catalyst (e.g. , Pd(dppf)Cl ₂ ). The resulting biaryl intermediate can then be coupled with a substituted primary or secondary amine to give 2-amino-5-aryl(or heteroaryl)-6-methylpyrazine. Additional deprotection and/or functionalization steps may be required to obtain the final compound.

Scheme 3. General synthesis of 3-amino-6-aryl-5-methylpyrazinyl-2-methanol and 3-amino-5-methyl-6arylsulfanylpyrazinyl-2-methanol.

The overall synthesis of 3-amino-6-aryl-5-methylpyrazinyl-2-methanol and 3-amino-5-methyl-6arylsulfanylpyrazinyl-2-methanol is shown in Scheme 3. Ethyl-6-bromo-3-chloro-5-methylpyrazin- The 2-carboxylate can be coupled with a substituted primary or secondary amine. The resulting aminopyrazine intermediate may be coupled with a substituted aryl- or heteroarylboronic acid or a substituted arylthiol in the presence of a palladium catalyst (eg Pd(dppf)Cl ₂ ) followed by a reduction step. Additional deprotection and/or functionalization steps may be required to obtain the final compound.

Alternatively, the aminopyrazine intermediate can be prepared from ethyl 3-chloro-5-methylpyrazine-2-carboxylate by coupling with

- 103 041617 substituted primary or secondary amine and subsequent bromination with NBS or an alternative bromination agent.

Methods of using the disclosed compounds and compositions.

Methods and uses of the present invention Another aspect of the present invention relates to a method of treating a disease associated with SHP2 modulation in a subject in need thereof. The method includes administering to a patient in need of treatment for diseases or disorders associated with SHP2 modulation, an effective amount of one or more compounds of the present invention (for example, compounds of formula I, I-W or I-W6 and their pharmaceutically acceptable salts, or stereoisomers) or one or more pharmaceutical compositions of the present invention. In some embodiments, the disease may be, without limitation, Noonan syndrome, Leopard syndrome, juvenile myelomonocytic leukemia, neuroblastoma, melanoma, acute myeloid leukemia, and breast, lung, and rectal cancers. SHP2 is an important downstream signaling molecule to a variety of receptor tyrosine kinases, including platelet growth factor (PDGF-R), fibroblast growth factor (FGF-R), and epidermal growth factor (EGF-R) receptors. SHP2 is also an important downstream signaling molecule for activation of the mitogen-activated protein kinase (MAP) pathway, which can lead to cell transformation, which is a prerequisite for cancer development. SHP2 knockdown significantly suppressed cell growth in lung cancer cell lines with SHP2 mutation or EML4/ALK translocations, as well as EGFR-amplified breast cancers and esophageal cancers. SHP2 is also upregulated following oncogenes in gastric carcinoma, anaplastic large cell lymphoma, and glioblastoma.

In addition, SHP2 plays a role in signaling generated by immune response checkpoint molecules, including, but not limited to, programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). In this context, modulation of SHP2 function can lead to immune activation, in particular to activation of anti-cancer immune responses.

Another aspect of the present invention is directed to a method for inhibiting SHP2. The method includes administering to a patient in need thereof an effective amount of one or more compounds of the present invention (I, I-W or I-W6 and their pharmaceutically acceptable salts or stereoisomers) or one or more pharmaceutical compositions of the present invention.

The present invention relates to compounds or compositions disclosed herein, which are capable of modulating the activity (eg, inhibition) of SHP2. The present invention also relates to the therapeutic use of such compounds and compositions.

One or more of the disclosed compounds or compositions may be administered in effective amounts to treat or prevent a disorder and/or prevent its development in subjects. In some embodiments, SHP2 is inhibited after treatment with less than 1000 nM of a compound of the present invention. In some embodiments, SHP2 is inhibited after treatment with about 10 to about 100 nM of a compound of the present invention. In some embodiments, SHP2 is inhibited after treatment with 10 to 100 nM of a compound of the present invention. In some embodiments, SHP2 is inhibited following treatment with less than 10 nM of a compound of the present invention.

Another aspect of the present invention relates to one or more compounds of the present invention (I, I-W or I-W6 and their pharmaceutically acceptable salts or stereoisomers) or one or more compositions of the present invention for use in the treatment or prevention of a disease associated with modulation SHP2. In some embodiments, the disease is Noonan's syndrome, Leopard's syndrome, juvenile myelomonocytic leukemia, neuroblastoma, melanoma, acute myeloid leukemia, and breast, lung, and rectal cancers.

SHP2 is an important downstream signaling molecule to a variety of receptor tyrosine kinases, including platelet growth factor (PDGF-R), fibroblast growth factor (FGF-R), and epidermal growth factor (EGF-R) receptors. SHP2 is also an important downstream signaling molecule for activation of the mitogen-activated protein kinase (MAP) pathway, which can lead to cell transformation, which is a prerequisite for cancer development. SHP2 knockdown significantly suppressed cell growth in lung cancer cell lines with SHP2 mutation or EML4/ALK translocations, as well as EGFR-amplified breast cancers and esophageal cancers. SHP2 is also upregulated following oncogenes in gastric carcinoma, anaplastic large cell lymphoma, and glioblastoma.

In one aspect, the present invention relates to one or more compositions containing one or more compounds of the present invention (I, I-W or I-W6 and their pharmaceutically acceptable salts or stereoisomers), for use as a drug. In some embodiments, the drug is used to treat or prevent a disease associated with SHP2 modulation.

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Pharmaceutical compositions and methods of administration of the present invention.

Another aspect of the present invention relates to pharmaceutical compositions containing one or more compounds of the present invention and a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier may further include an excipient, diluent or surfactant.

Compositions may be prepared by conventional mixing, granulating or coating methods, in that order, and present pharmaceutical compositions may contain from about 0.1% to about 99%, from about 5% to about 90%, or from about 1% to about 20% of the disclosed compounds by weight or volume.

Administration of the disclosed compounds and pharmaceutical compositions may be by any route of administration of therapeutic agents. Such methods include systemic or topical administration, such as oral, nasal, parenteral, intravenous, transdermal, subcutaneous, vaginal, buccal, rectal, or topical routes of administration.

Depending on the intended mode of administration, the disclosed compounds or pharmaceutical compositions may be presented as solid, semi-solid or liquid dosage forms, such as injectables, tablets, suppositories, pills, sustained release capsules, tinctures, tinctures, emulsions, syrups, powders, liquids, suspensions or the like, sometimes in unit doses and in accordance with normal pharmaceutical practice. Likewise, they may also be administered in intravenous (both bolus and infusion), intraperitoneal, subcutaneous or intramuscular forms, all forms being well known to those skilled in the pharmaceutical arts.

Illustrative pharmaceutical compositions.

are tablets and gelatin capsules containing one or more compounds of the present invention and a pharmaceutically acceptable carrier such as, but not limited to a) a diluent such as purified water, triglyceride oils such as hydrogenated or partially hydrogenated vegetable oil, or mixtures thereof, corn oil , olive oil, sunflower oil, safflower oil, fish oils such as EPA or DHA or their esters or triglycerides or mixtures thereof, omega-3 fatty acids or their derivatives, lactose, dextrose, sucrose, mannitol, sorbitol, cellulose, sodium, saccharin, glucose and/or glycine; b) a lubricant, for example silica, talc, stearic acid, its magnesium or calcium salt, sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride and/or polyethylene glycol; for tablets also; c) a binder, such as magnesium aluminum silicate, starch paste, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose, magnesium carbonate, natural sugars such as glucose or beta-lactose, corn sweeteners, natural and synthetic gums such as gum arabic, tragacanth or alginate sodium, waxes and/or polyvinylpyrrolidone, if necessary; d) disintegrant, for example starches, agar, methylcellulose, bentonite, xanthan gum, alginic acid or its sodium salt, or effervescent mixtures; e) absorbent, colorant, flavoring agent and sweetener; f) an emulsifier or dispersant such as Tween 80, Labrasol, HPMC, DOSS, Caproyl 909, Labrafac, Labrafil, Peceol, Transcutol, Capmul MCM, Capmul PG-12, Captex 355, Gelucir, Vitamin E TGPS or other suitable emulsifier, and/or e) an absorption enhancing agent such as cyclodextrin, hydroxypropyl cyclodextrin, PEG400, PEG200.

Liquid, in particular injectable, compositions can be obtained, for example, by dissolution, dispersion, etc. For example, one or more of the disclosed compounds is dissolved in or mixed with a pharmaceutically acceptable solvent such as, for example, water, saline, aqueous dextrose, glycerol, ethanol, etc., thereby forming an injectable isotonic solution or suspensions. Proteins such as albumin, chylomicron particles or serum proteins can be used to dissolve the disclosed compounds.

One or more of the disclosed compounds or compositions may also be formulated into a suppository which may be prepared from fatty acid emulsions or suspensions using polyalkylene glycols such as propylene glycol as carrier.

One or more of the disclosed compounds or compositions may also be administered as liposomal delivery systems such as small monolamellar vesicles, large monolamellar vesicles, and multilamellar vesicles. Liposomes can be obtained from a variety of phospholipids containing cholesterol, stearylamine or phosphatidylcholines. In some embodiments, a film of lipid components is hydrated with an aqueous drug solution to form a drug-encapsulating lipid layer as described, for example, in US Pat. No. 5,262,564, the contents of which are incorporated herein by reference.

One or more of the disclosed compounds or compositions can also be delivered using monoclonal antibodies as separate carriers to which the disclosed compounds are attached. The disclosed compounds can also be attached to soluble polymers as carriers for targeted drug delivery. Such polymers may include polyvinylpyrrolidone, a pyran copolymer, polyhydroxypropyl methacrylamide phenol, polyhydroxyethyl laspanamide phenol, or polyethylene oxide polylysine substituted with palmitoyl residues. In addition, one or more of the disclosed compounds can be attached to polymers of the biodegradable class that are useful for achieving controlled drug release, such as polylactic acid, polyepsilon-caprolactone, polyhydroxybutyric acid, polyorthoesters, polyacetals, polydihydropyrans, polycyanoacrylates, and cross-linked or amphipathic hydrogel block copolymers. . In some embodiments, one or more of the disclosed compounds is non-covalently bonded to a polymer, such as a polycarboxylic acid polymer, or a polyacrylate.

One or more of the disclosed compounds or compositions can be delivered by parenteral administration. Parenteral administration of an injectable preparation is usually used for subcutaneous, intramuscular or intravenous injections and infusions. Injectable preparations may be prepared in conventional forms, either as liquid solutions or suspensions, or as solid forms suitable for dissolution in a liquid prior to injection.

Dosing regimens of the present invention.

The dosage regimen using the disclosed compound is selected based on a variety of factors, including the type, species, age, weight, sex, and health of the patient; the severity of the condition being treated; route of administration; the functioning of the patient's kidneys or liver; and the specific disclosed compound used. A physician or veterinarian of ordinary skill in the art can readily determine and prescribe the effective amount of the drug needed to prevent, counteract, or halt the progression of the condition.

Effective dosage amounts of the disclosed compounds, if used to produce the indicated effects, range from about 0.5 mg to about 5000 mg of the disclosed compound as needed to treat the condition. Compositions for in vivo or in vitro use may contain about 0.5, 5, 20, 50, 75, 100, 150, 250, 500, 750, 1000, 1250, 2500, 3500, or 5000 mg of the disclosed compound, or the amount may be in the range from one value to another value in the list of doses. In some embodiments, the compositions are in the form of a tablet that can be divided along a break line.

If desired, an effective daily dose of one or more compounds or compositions of the present invention may be administered as one, two, three, four, five, six, or more portions of doses administered separately at appropriate intervals throughout the day, optionally as single doses. dosage forms. In some embodiments of the present invention, one or more compounds or compositions of the present invention, or mixtures thereof, can be administered two or three times a day. In some embodiments, one or more compounds or compositions of the present invention will be administered once a day.

In some embodiments, one or more of the compounds or compositions described herein may be used alone, or administered together, or concurrently, or used in combination with another type of therapeutic agent. Co-administration or used in combination refers to any form of administration of two or more different therapeutic compounds or compositions in which the second compound or composition is administered while the previously administered therapeutic compound or composition is still effective in the body. For example, different therapeutic compounds or compositions can be administered either in the same formulation, or in a separate formulation, or simultaneously, sequentially, or by separate dosing of the individual components of the treatment. In some embodiments, different therapeutic compounds or compositions can be administered within one hour, 12, 24, 36, 48, 72 hours, or weeks apart. Thus, an individual who receives such treatment may benefit from the combined action of different therapeutic compounds or compositions.

Examples

The present invention is further illustrated by the following Examples and Synthesis Examples, which should not be construed as limiting the scope and spirit of the present invention to the specific procedures described herein. It should be understood that the examples are provided to illustrate certain embodiments and are not intended to limit the scope of the invention. Additionally, it should be understood that various other embodiments, modifications and their equivalents can be applied, which can be offered to experts in the art, without departing from the essence of the present invention and/or the scope of the appended claims.

The definitions used in the following examples and other parts of this document are:

CH ₂ Cl ₂ , DCM - methylene chloride, dichloromethane;

CH3CN, MeCN - acetonitrile;

CuI - copper(T) iodide;

DIPEA - diisopropylethylamine;

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DMF - Ν,N-dimethylformamide;

equiv. - equivalent;

ESI - electrospray ionization;

EtOAc - ethyl acetate;

Hr - hour;

H2O - water;

HCl - hydrochloric acid;

HPLC - high performance liquid chromatography;

K3PO4 - potassium phosphate (tribasic);

LC-MS - liquid chromatography with mass spectrometry;

MeOH - methanol;

min - minute(s);

Na2SO4 - sodium sulfate;

NMP - N-methylpyrrolidone;

NMR - nuclear magnetic resonance;

Pd(dppf)Cl ₂ - [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II);

TLC - thin layer chromatography.

Examples 1-93.

Example 1 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1 amine.

Stage 1. Synthesis of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-methylpyrazine.

To a solution of 2-bromo-5-chloro-3-methylpyrazine (50 mg, 241.01 µmol, 1 eq.) in dioxane (3 ml) under an inert atmosphere at 20°C was successively added 2,3-dichlorobenzenethiol (64.74 mg, 361.52 µmol, 1.5 eq.), CuI (9.18 mg, 48.20 µmol, 0.2 eq.), K3PO4 (102.32 mg, 482.02 µmol, 2 eq.) and 1,10 phenanthroline (17.37 mg, 96.40 µmol, 0.4 eq.). The resulting mixture was stirred at 80° C. for 0.5 h. The reaction mixture was then cooled and H ₂ O (20 ml) was added to the solution. The resulting aqueous phase was extracted with ethyl acetate (4x10 ml) and the combined organic extracts were washed with brine (2x10 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified to give 5-chloro-2-((2,3dichlorophenyl)thio)-3-methylpyrazine (25.00 mg, 34% yield) as a light yellow solid. LCMS (ESI): mass/charge: [M+H] calc. for CnH ₇ Cl ₃ N ₂ S: 304.94; the found value is 305.0.

Stage 2. Synthesis of N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)-2-methylpropane -2-sulfinamide.

To a solution of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-methylpyrazine (25 mg, 81.80 µmol, 1 eq.) and 2methyl-N-((R)-8-α3αspiro[4.5 ]decan-1-yl)propan-2-sulfinamide (42.28 mg, 163.61 µmol, 2 eq.) in NMP (1 ml) in an inert atmosphere at 20°C was added DIPEA (84.58 mg, 654, 43 µmol, 114.30 µl, 8 eq.). The mixture was then stirred at 120° C. for 12 hours. The reaction mixture was then cooled and H ₂ O (20 ml) was added to the solution. The resulting aqueous phase was then extracted with ethyl acetate (4x10 ml). The combined organic extracts were washed with brine (2x10 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give crude N-((R)-8-(5-((2,3-dichlorophenyl)thio) -6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2methylpropan-2-sulfinamide (30 mg) as a black-brown solid, which was used directly in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₄ H ₃₂ Cl ₂ N ₄ OS ₂ : 527.14; the found value is 527.1.

Step 3. Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1 amine.

To a solution of N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2methylpropan-2 -sulfinamide (30 mg, 56.86 μmol, 1 eq.) in MeOH (1 ml) HCl in MeOH (4 M, 3 ml) was added under an inert atmosphere at 20°C.

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The resulting mixture was stirred at 20° C. for 1 hour. The reaction mixture was then concentrated under reduced pressure to obtain a crude product. This crude residue was purified by preparative HPLC to give (R)-8-(5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine (7 01 mg, 29.12% yield as a solid. ¹ H NMR (400 MHz, methanol^) δ 8.12 (br s, 1H), 7.34 (d, J=7.72 Hz, 1H), 7.12 (t, J=7.94 Hz, 1H), 6.69 (d, J=7.72 Hz, 1H), 7.12 (t, mass/charge: [M+H] calcd for C ₂₀ H ₂₄ Cl ₂ N ₄ S: 423.11 ; found value 423.1.

Example 2 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine.

-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to the method in example 1, except that 2-methyl- N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(4-methylpiperidin-4yl)carbamate. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.26 (s, 4H), 7.48-7.46 (m, 1H), 7.26-7.22 (m, 1H), 6, 75 (d, J=8 Hz, 1H), 4.09-4.06 (m, 2H), 3.40 (m, 2H), 2.38 (s, 3H), 1.79-1.74 (m, 4H), 1.37 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ Cl ₂ N ₄ S: 383.08; the found value is 383.1.

Example 3 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-N,4-dimethylpiperidin-4amine.

Stage 1. Synthesis of tert-butyl-(1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4methylpiperidin-4-yl)(methyl)carbamate.

To a solution of tert-butyl-(1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (150.00 mg, 310.27 µmol, 1.00 eq) in THF (5.00 mL) sodium hydride (12.41 mg, 310.27 µmol, 60% purity, 1 eq) was added portionwise at 0° C. under an inert atmosphere. The mixture was stirred at 0°C for 30 min and then methyl iodide (44.04 mg, 310.27 µmol, 19.32 µl, 1 eq.) was added dropwise at 0°C. The mixture was stirred at 0°C and stirred for 1.5 h, after which the reaction mixture was quenched by adding water (50 ml) and was extracted with EtOAc (3x20 ml). The combined organic layers were washed with brine (2x20 ml), dried over sodium sulfate, filtered and concentrated under reduced pressure to give the methylated product as a yellow solid (110.00 mg, crude). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₃ H3 ₀ Cl ₂ N ₄ O ₂ S: 497.15; found value: 497.1; RT=1.12 min.

Step 2 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-N,4-dimethylpiperidin-4-amine.

1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-N,4-dimethylpiperidin-4-amine was synthesized by a method similar to that of Example 1, except that N -((R)-8-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide was replaced by tert-butyl-(1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4yl)(methyl)carbamate. 1H NMR (400 MHz, chloroform-d) δ ppm 8.38 (s, 1H), 7.93 (s, 1H), 3.87-3.84 (m, 1H), 3.56-3.44 (m, 1H), 2.40 (s, 3H), 1.74 (br d, J=4.15 Hz, 1H), 1.35-1.29 (m, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ S: 397.09; found value: 396.9.

Example 4 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-aminomethyl-4methylpiperidine.

1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-aminomethyl-4-methylpiperidine was synthesized by a method similar to that of Example 1, except that 2-methyl -N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-((4-methylpiperidin-4yl)methyl)carbamate. 1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-aminomethyl-4methylpiperidine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSOd6) δ 8.36 (s, 1H), 8.22 (d, J=0.7 Hz, 1H), 7.46 (dd, J=8.0, 1.4 Hz , 1H), 7.23 (t, J=8.0 Hz, 1H), 6.72 (dd, J=8.0, 1.4 Hz, 1H), 7.23 (t, J=13, 5, 5.0 Hz, 2H), 3.40 (ddd, J=13.3, 9.6, 3.5 Hz, 2H), 2.57 (s, 2H), 2.38 (s, 3H ), 1.49 (ddd, J=13.7, 9.6, 4.1 Hz, 2H), 1.36 (dt, J=13.5, 4.5 Hz, 2H), 1.00 ( s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ S: 397.09; the found value is 397.39.

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Example 5 Synthesis of (1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidin4-yl)methanamine.

Synthesis of 4-(pyridin-3-yl)piperidine-4-carbonitrile.

Synthesis of 4-(pyridin-3-yl)piperidine-4-carbonitrile. To a mixture of tert-butyl-4-cyanopiperidine-1-carboxylate (500 mg, 2.3 mmol, 1 eq.) and 3-chloropyridine (405 mg, 3.5 mmol, 340 μl, 1.5 eq.) in toluene ( 10 ml) LiHMDS (1 M, 7.1 ml, 3 eq.) and Pd(t-Bu ₃ P) ₂ (243 mg, 476 μmol, 0.2 eq.) were added in one portion at 25°C in an inert atmosphere . The mixture was stirred at 25°C for 2 h and then heated to 90°C for 15 h. Then the reaction mixture was poured into H ₂ O (5 ml) and the aqueous phase was extracted with ethyl acetate (3x10 ml). The combined organic phase was washed with brine (2 ml), dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography to give tert-butyl 4-cyano-4(pyridin-3-yl)piperidine-1-carboxylate (180 mg, 626 μmol, 26% yield) as a yellow oil. 1H NMR (400 MHz, chloroform-d) δ 8.64 (br s, 1H), 8.51 (br d, J=3.53 Hz, 1H), 7.69 (br d, J=7.94 Hz, 1H), 7.25 (dd, J=7.94, 4.85 Hz, 1H), 7.14 (s, 1H), 4.32-4.11 (m, 2H), 3.09 (br s, 2H), 2.01 (br d, J=12.8 Hz, 2H), 1.91-1.79 (m, 3H), 1.37 (s, 9H), 1.36- 1.32 (m, 2H), 1.15-1.12 (m, 1H), 1.09 (s, 1H). Deprotection with HCl (4N, dioxane) provided 4-(pyridin-3yl)piperidine-4-carbonitrile hydrochloride, which was used in the next step without further purification.

Step 1. Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidine-4carbonitrile.

5-Chloro-2-((2,3-dichlorophenyl) thio)-3-methylpyrazine (80 mg, 427 µmol, 1.2 eq.) at 120° C. under an inert atmosphere. The mixture was stirred at 120°C for 15 h before being poured into H ₂ O (5 ml) and then the aqueous phase was extracted with ethyl acetate (3x5 ml). The combined organic extracts were washed with brine (1 ml), dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography to give 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3yl)piperidine-4-carbonitrile (60 mg, 131 µmol, 37% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.80 (d, J=2.19 Hz, 1H), 8.65 (d, J=4.82 Hz, 1H), 8.07 (s, 1H ), 7.85 (dd, J=8.11, 1.53 Hz, 1H), 7.40 (dd, J=7.89, 4.82 Hz, 1H), 7.30 (dd, J= 8.33, 1.32 Hz, 1H), 7.06 (t, J=8.11 Hz, 1H), 6.83-6.78 (m, 1H), 5.31 (s, 1H), 4.62 (br d, J=14.03 Hz, 2H), 3.44 (br t, J=13.15 Hz, 2H), 2.53 (s, 3H), 2.31 (br d, J=12.28 Hz, 2H), 2.19-2.09 (m, 2H).

Stage 2. Synthesis of tert-butyl-((1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3yl)piperidin-4-yl)methyl) carbamate.

To a solution of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidine-4carbonitrile (60 mg, 131 µmol, 1 eq.) lithium aluminum hydride (30 mg, 788 μmol, 6 eq.) was added in one portion to THF (5 ml) at 0° C. under an inert atmosphere. The mixture was stirred at 0° C. for 2 h before H ₂ O (0.1 ml) was added dropwise to the reaction mixture to give a cloudy liquid. This mixture was then diluted with THF (10 ml) before adding Boc ₂ O (85 mg, 391 μmol, 90 μl, 3 eq.) at 25°C under N2 atmosphere. The mixture was stirred at 25°C for 2 h before the mixture was filtered and concentrated in vacuo. The residue was purified by column chromatography to give tert-butyl-((1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidin- 4yl)methyl)carbamate (27 mg, 51 µmol, 39% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.73-8.46 (m, 2H), 8.00 (s, 1H), 7.71 (br d, J=6.58 Hz, 1H), 7.38 (br s, 1H), 7.25 (br d, J=8.33 Hz, 1H), 7.01 (t, J=7.89 Hz, 1H), 6.67 (d, J =7.89 Hz, 1H), 6.67 (d, J=5.26 Hz, 3H), 2.47 (s, 3H), 2.25 (br s, 2H), 2.00 (br s , 2H), 1.40 (s, 9H), 1.31-1.23 (m, 1H).

Step 3 Synthesis of (1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidin4-yl)methanamine.

Synthesis of (1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-(pyridin-3-yl)piperidin-4yl)methanamine was carried out by a method similar to the method in example 1 1H NMR (400 MHz, methanol-d ₄ ) δ 8.72 (s, 1H), 8.56 (d, J=4.63 Hz, 1H), 8.49 (br s, 1H), 8, 08 (s, 1H), 8.03 (br d, J=8.16 Hz, 1H),

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7.56 (dd, J=7.94, 4.85 Hz, 1H), 7.34 (d, J=7.94 Hz, 1H), 7.11 (t, J=8.05 Hz, 1H ), 6.67 (d, J=7.72 Hz, 1H), 4.16 (br d, J=13.45 Hz, 2H), 3.35-3.33 (m, 1H), 3. 28 (br s, 1H), 3.23 (s, 2H), 2.44 (s, 5H), 2.01 (br t, J=10.14 Hz, 2H).

LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₃ Cl ₂ N ₅ S: 460.11; the found value is 459.9.

Example 6 Synthesis of (R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-amine.

Stage 1. Synthesis of 4-bromo-3-chloropyridine-2-amine.

Three separate batches of 4-bromo-3-chloro-2-fluoropyridine (3x8.00 g, 3x38.02 mmol, 3x1 eq.) and NH3-H2O (3x60 ml) were stirred at 120°C for 2 h, after which three batches were pooled and concentrated to reduce the solution volume. The aqueous phase was then extracted with dichloromethane (3x50 ml) and the combined organic extracts washed with brine (2x50 ml), dried over anhydrous sodium sulfate, filtered and concentrated to give 4-bromo-3-chloropyridine-2amine (22.06 g, 106.33 mmol, 93% yield) as a white solid. Ή NMR (400 MHz, chloroform-d) δ 7.76 (d, J=5.26 Hz, 1H), 6.91 (d, J=5.26 Hz, 1H), 5.06 (br, 2H ).

Stage 2. Synthesis of 2-ethylhexyl-3-((2-amino-3-chloropyridin-4-yl)thio)propanoate.

To a solution of 4-bromo-3-chloropyridin-2-amine (5 g, 24.1 mmol, 1 eq.) in dioxane (50 ml) was added 2-ethylhexyl-3-sulfanylpropanoate (5.2 g, 24.1 mmol, 1 eq.), Xantphos (1.3 g, 2.4 mmol, 0.1 eq.), Pd ₂ (dba) ₃ (831 mg, 1.4 mmol, 0.06 eq.), DIPEA (8.4 ml, 48.2 mmol, 2 equiv.) at 20°C. The mixture was then heated to 110° C. and stirred for 5 hours under an inert atmosphere. After this time, the reaction mixture was diluted with H ₂ O, the aqueous phase was extracted with dichloromethane (3x50 ml). The combined organic extracts were washed with brine (2x50 ml), dried over anhydrous sodium sulfate, filtered and concentrated. The reaction mixture was vigorously stirred and then filtered to give 2-ethylhexyl-3-((2-amino-3-chloropyridin-4-yl)thio)propanoate (5 g, 14.7 mmol, 61% yield) as light green solid. ¹ H NMR (400 MHz, chloroform-d) δ ppm 7.85 (d, J=5.51 Hz, 1H), 6.50 (d, J=5.51 Hz, 1H), 6.50 (d , J=5.84, 1.21 Hz, 2H), 3.20 (t, J=7.50 Hz, 2H), 2.71 (t, J=7.39 Hz, 2H), 1.66 -1.51 (m, 3H), 1.45-1.31 (m, 2H), 1.27 (br s, 5H), 0.87 (t, J=7.39 Hz, 6H).

Stage 3. Synthesis of 2-amino-3-chloropyridine-4-thiol.

To a solution of 2-ethylhexyl-3-((2-amino-3-chloropyridin-4-yl)thio)propanoate (5 g, 14.5 mmol, 1 eq.) in THF (50 ml) at -78°C in potassium tert-butoxide (1M in THF, 29 mL, 29 mmol, 2 eq.) was added under an inert atmosphere. The reaction mixture was stirred at -78°C for 1 h, after which the reaction mixture was filtered and concentrated. The crude residue was purified with a silica gel column to give 2-amino-3-chloropyridine-4-thiol (1.9 g, 11.8 mmol, 81% yield) as a yellow solid.

Stage 4. Synthesis of 3-chloro-4-((5-chloro-3-methylpyrazin-2-yl)thio)pyridine-2-amine.

DIEA (8.08 ml, 46.2 mmol, 2 eq.), 2-bromo-5-chloro-3-methylpyrazine (4.80 g, 23.1 mmol, 1 eq.), Xantphos (1.34 g, 2.31 mmol, 0.1 eq. .) and Pd ₂ (dba) ₃ (1.69 g, 1.85 mmol, 0.08 eq.). The reaction mixture was stirred at 80°C for 1 h, after which the reaction mixture was concentrated. The residue was purified with a silica gel column to give 3-chloro-4-((5-chloro-3-methylpyrazin-2yl)thio)pyridin-2-amine (3.20 g, 11.1 mmol, 48% yield) in form of a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 8.23 (s, 1H), 7.82 (d, J=5.29 Hz, 1H), 6.44 (d, J=5.29 Hz, 1H ), 4.93 (br s, 2H), 2.56 (s, 3H).

Step 5. Synthesis of (R)-N-((R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-ul)-8azaspiro[4.5] decan-1-yl)-2-methylpropan-2-sulfinamide.

To a solution of 3-chloro-4-((5-chloro-3-methylpyrazin-2-yl)thio)pyridin-2-amine (750 mg, 2.61 mmol, 1 eq.) in DIEA (9.00 ml) and NMP (3.00 ml) was added (R)-2-methyl-N-((R)-8-azaspuro[4.5]decan-1-yl)propan2-sulfinamide (1.01 g, 3.92 mmol, 1.5 eq.). The reaction mixture was stirred at 100°C for 2 h, after which the reaction mixture was concentrated under reduced pressure. The crude residue was purified with a silica gel column to give (R)-N-((R)-8-(5-((2-amino-3-chloropyridin-4yl)thio)-6-methylpyrazin-2-yl)- 8-azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide (750 mg, 1.47 mmol, 56% yield) as a solid.

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Step 6. Synthesis of (R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-amine.

Mixture of (R)-N-((R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1 -yl)-2-methylpropan-2-sulfinamide (1.00 g, 1.96 mmol, 1 eq.) in HCl/MeOH (10 ml) was stirred at 20°C for 1 h, after which the reaction mixture was concentrated at reduced pressure. The residue was purified by HPLC to give (R)-8-(5-((2-amino-3-chloropyridin-4yl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1- amine (350 mg, 864 µmol, 44% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.03 (s, 1H), 7.62 (d, J=5.51 Hz, 1H), 5.88 (d, J=5.51 Hz, 1H ), 5.88 (d, J=14.33 Hz, 2H), 3.13 (br s, 2H), 2.98 (br s, 1H), 2.44 (s, 3H), 1.26 -1.92(m, 10H). LCMS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₅ Cl ₂ N ₆ S: 405.15; the found value is 405.0.

Example 7 Synthesis of 4-((5-(4-amino-4-methylpiperidin-1-yl)-3-methylpyrazin-2-yl)thio)-3chloropyridin-2-amine.

4-((5-(4-Amino-4-methylpiperidin-1-yl)-3-methylpyrazin-2-yl)thio)-3-chloropyridin-2-amine was synthesized by a method similar to the method in example 6, except that (R)-2-methyl-N((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by 4-methylpiperidin-4-amine. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.52 (s, 1H), 8.18 (s, 1H), 7.57 (d, J=5.70 Hz, 1H), 5.78 ( d, J=5.70 Hz, 1H), 5.78 (d, LC-MS (ESI): mass/charge: [M+H] calcd for C ₁₆ H ₂₁ ClN ₆ S: 365.1; found the value is 365.1.

N-(3-Bromo-2-chlorophenyl)-2,2,2-trifluoroacetamide.

Cl Cl η=νΡ%Βγ F ₃ C νΡ,Βγ

U Ϊ and

To a solution of 3-bromo-2-chloroaniline (8 g, 39 mmol, 1 eq.) in DCM (80 ml) under an inert atmosphere at 0°C was added triethylamine (16.11 ml, 116 mmol, 3 eq.) followed by adding trifluoroacetic anhydride (8.1 ml, 58 mmol, 1.5 eq.). The resulting mixture was then heated to 20° C. and stirred for 2 h. After this time, the reaction mixture was quenched with H2O (100 ml) and extracted with DCM (3x150 ml). The combined organic extracts were washed with brine (140 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give N-(3-bromo-2-chlorophenyl)-2,2,2-trifluoroacetamide (10 g, 33 mmol, 85% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.48 (s, 1H), 8.34-8.31 (m, 1H), 7.53-7.51 (m, 1H), 7.26- 7.21 (m, 1H).

Example 8 Synthesis of (R)-8-(5-((3-amino-2-chlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan1-amine

CL Me

(R)-8-(5-((3-Amino-2-chlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to that of Example 6, except that 4-bromo-3-chloropyridine-2-amine was replaced by N-(3-bromo-2-chlorophenyl)-2,2,2-trifluoroacetamide. 1H NMR (400 MHz, methanol-d4) δ 8.54 (s, 1H), 8.65-8.47 (m, 1H), 8.02 (s, 1H), 6.85 (t, J= 7.94 Hz, 1H), 6.64 (dd, J=8.05, 1.43 Hz, 1H), 5.99 (dd, J=7.72, 1.32 Hz, 1H), 4, 42-4.19 (m, 2H), 3.20-3.04 (m, 2H), 2.41 (s, 2H), 2.22-2.13 (m, 1H), 2.04- 2.34 (m, 8H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₆ ClN ₅ S: 404.16; the found value is 404.1.

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Example 9 Synthesis of 4-((5-(4-(aminomethyl)-4-methylpiperidin-1-yl)-3-methylpyrazin-2-yl)thio)-3chloropyridin-2-amine.

Stage 1. Synthesis of tert-butyl-4-cyano-4-methylpiperidine-1-carboxylate.

LDA (2 M in THF, 7.85 ml, 1.1 eq) for 15 min. The resulting yellow solution was stirred at -78° C. for 30 minutes before iodomethane (1.33 ml, 21.4 mmol, 1.5 eq.) was added dropwise. The reaction mixture was stirred at -78°C for 30 min before it was heated to 25°C and stirred for 1 h. After this time, the reaction mixture was carefully poured into 100 ml of ice water and the organic layer was separated. The aqueous phase was extracted with ethyl acetate (3x100 ml). The combined organic extracts were washed with brine (5 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by column chromatography to give tert-butyl 4-cyano-4-methylpiperidine-1-carboxylate (1.82 g, 8.11 mmol, 56% yield) as a white solid. ¹ H NMR (400 MHz, chloroform-d) δ 4.22-3.93 (m, 2H), 3.00 (br s, 2H), 1.85 (br d, J=13.23 Hz, 2H ), 1.47-1.31 (m, 14H).

Stage 2. Synthesis of 4-methylpiperidine-4-carbonitrile.

To a solution of HCl/EtOAc (4 M, 20 ml) in an inert atmosphere was added tert-butyl-4-cyano-4-methylpiperidine-1-carboxylate (1.82 g, 8.11 mmol, 1 eq.) at 25°C. The mixture was stirred at 25° C. for 3 h after which the reaction mixture was filtered and concentrated under reduced pressure to give 4-methylpiperidine-4-carbonitrile (1.46 g, crude, HCl salt) as a white solid. 1H NMR (400 MHz, methanol^) δ 3.45 (br d, J=13.67 Hz, 2H), 3.16 (td, J=13.34, 2.65 Hz, 2H), 2.19 (br d, J=14.11 Hz, 2H), 1.74-1.86 (m, 2H), 1.46 (s, 3H).

Step 3 Synthesis of 1-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-4methylpiperidin-4-carbonitrile.

A mixture of 4-methylpiperidin-4-carbonitrile (200 mg, 696 µmol, 1 eq) and 3-chloro-4-((5-chloro-3methylpyrazin-2-yl)thio)pyridine-2-amine (112 mg, 696 µmol, 1 eq.) in DIPEA (2.00 ml) was stirred at 120°C in an inert atmosphere for 2 h. The reaction mixture was then poured into H ₂ O (5 ml) and the aqueous phase was extracted with EtOAc (3x5 ml) . The combined organic extracts were washed with brine (1 ml), dried with anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was then purified by column chromatography to give 1-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidine4-carbonitrile (100 mg, 266 µmol, 38% yield as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.05 (s, 1H), 7.67 (d, J=5.29 Hz, 1H), 5.87 (d, J=5.51 Hz, 1H ), 4.84 (br s, 2H), 4.43 (br d, J=13.01 Hz, 2H), 3.26 (br t, J=12.24 Hz, 2H), 2.47 ( s, 3H), 2.07 (br s, 1H), 1.41-1.47 (m, 4H).

Step 4 Synthesis of 4-((5-(4-(aminomethyl)-4-methylpiperidin-1-yl)-3-methylpyrazin-2-yl)thio)-3chloropyridin-2-amine.

To a mixture of 1-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidine-4carbonitrile (100 mg, 266 µmol, 1.00 eq. ) in THF (2.60 ml) under an inert atmosphere at -78° C. LAH (60.7 mg, 1.60 mmol, 6 eq.) was added in one portion. The mixture was stirred at 25° C. for 2 hours. After this time, H ₂ O (0.1 ml) was added dropwise to the reaction mixture. The resulting mixture was filtered and the filtrate was concentrated under reduced pressure to give a crude product. The residue was purified by HPLC to 4-((5-(4-(aminomethyl)-4-methylpiperidin-1yl)-3-methylpyrazin-2-yl)thio)-3-chloropyridin-2-amine (500 µg, 1, 32 µmol, 0.49% yield as a white solid. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.11 (s, 1H), 7.56 (d, J=5.51 Hz, 1H), 5.77 (d, J=5.73 Hz, 1H), 4.58 (s, 2H), 4.09 (s, 2H), 3.47 (br s, 3H), 2.87 (s, 2H), 2.43 (s, 3H), 1 .57 (br s, 4H), 1.27 (s, 1H), 1.17 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₄ ClN6S: 379.1; the found value is 379.2.

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Example 10 Synthesis of (R)-8-(5-((2,3-difluorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1 amine

(R)-8-(5-((2,3-Difluorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to the method in example 1, except that 2,3-dichlorobenzenethiol was replaced by 2,3-difluorobenzenethiol. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.52-8.50 (m, 2H), 7.98 (s, 2H), 7.19-7.17 (m, 1H), 7.15 -7.13(m, 1H), 7.07-7.04(m, 1H), 4.32-4.24(m, 2H), 3.19-3.14(m, 2H), 2 .46 (s, 3H), 2.32-2.23 (m, 1H), 1.88-1.32 (m, 10 H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₄ F ₂ N ₄ S: 391.17; the found value is 391.0.

Example 11 Synthesis of 1-(5-((2,3-difluorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

1-(5-((2,3-Difluorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to the method in example 1, except that 2.3 -dichlorobenzenethiol and (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide were replaced by 2,3difluorobenzenethiol and 4-methylpiperidin-4-amine, respectively . 1H NMR (400 MHz, methanol-d ₄ ) δ 8.53 (s, 1H), 8.01 (s, 1H), 7.18-7.17 (m, 1H), 7.16-7.08 (m, 1H), 6.95-6.91 (m, 1H), 4.12-4.09 (m, 2H), 3.43-3.41 (m, 2H), 2.47 (s , 3H), 1.83-1.81 (m, 4H), 1.45 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ F ₂ N ₄ S: 351.14; the found value is 351.2.

Example 12 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

CL Me

1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to the method in example 6, except that 4-bromo -3-chloropyridine-2amine was replaced by 2,3-dichloro-4-iodopyridine. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.53 (s, 1H), 8.17 (s, 1H), 7.98 (d, J=5.26 Hz, 1H), 6.54 ( d, J=5.26 Hz, 1H), 6.54 (d, calculated for C^^Ch^S: 424.11; found value: 424.1.

Example 13 Synthesis of 5-(4-amino-4-methylpiperidin-1-yl)-N-(2,3-dichlorophenyl)-3-methylpyrazin-2amine

Stage 1. Synthesis of tert-butyl-(1-(5-bromo-6-methylpyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate.

To a mixture of 2-bromo-5-chloro-3-methylpyrazine (300 mg, 1.5 mmol, 1 eq.) and tert-butyl-(4methylpiperidin-4-yl)carbamate (373 mg, 1.7 mmol, 1, 1 eq.) in DMA (4 ml) in an inert atmosphere was added Cs ₂ CO ₃ (945 mg, 2.9 mmol, 1.9 eq.). The resulting mixture was heated to 70°C and stirred for 3 h before the reaction mixture was cooled and concentrated under reduced pressure. The crude residue was purified by preparative TLC to give tert-butyl-(1(5-bromo-6-methylpyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate (90 mg, 234 μmol, 16% yield). 1H

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NMR (400 MHz, chloroform-d) δ 7.68 (s, 1H), 4.39 (br, s, 1H), 3.83-3.78 (m, 2H), 3.31-3.25 (m, 2H), 2.48 (s,

3H), 2.10-2.07 (m, 2H), 1.66-1.61 (m, 2H), 1.43 (s, 9H), 1.38 (s, 3H).

Step 2. Synthesis of tert-butyl-(1-(5-((2,3-dichlorophenyl)amino)-6-methylpyrazin-2-yl)-4methylpiperidin-4-yl)carbamate.

To a solution of tert-butyl-(1-(5-bromo-6-methylpyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate (45 mg, 117 µmol, 1 eq.) in toluene (1.5 ml ) at 20°C in an inert atmosphere, 2,3dichloroaniline (21 μl, 175 μmol, 1.5 eq.), sodium tert-butoxide (22.5 mg, 234 μmol, 2 eq.), Pd ₂ (dba) were added sequentially ₃ (10.7 mg, 11.7 µmol, 0.1 eq.), BINAP (14.5 mg, 23.4 µmol, 0.2 eq.). The resulting mixture was heated to 125°C for 1.5 h using microwave radiation. At the end of this time, the mixture was cooled and concentrated under reduced pressure, and the crude residue was purified by preparative TLC to give t-butyl-(1-(5-((2,3-dichlorophenyl)amino)-6methylpyrazin-2-yl)-4 -methylpiperidin-4-yl)carbamate (50 mg, 107 µmol, 46% yield) as a yellow oil. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₉ Cl ₂ N ₅ O ₂ : 466.17; the found value is 466.2.

Stage 3. Synthesis of 5-(4-amino-4-methylpiperidin-1-yl)-N-(2,3-dichlorophenyl)-3-methylpyrazin-2amine.

A solution of tert-butyl-(1-(5-((2,3-dichlorophenyl)amino)-6-methylpyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (50 mg, 107 µmol, 1 eq.) in TFA (1 ml) and DCM (1 ml) were stirred at 20° C. for 2 hours. After this time, the pH of the mixture was adjusted to pH 8 with sat. _NaHC03 . The resulting mixture was extracted with DCM (3x5 ml). The organic extracts were washed with brine (5 ml), dried over Na ₂ SO ₄ , filtered and concentrated. The resulting crude residue was purified by preparative HPLC to give 5-(4-amino-4methylpiperidin-1-yl)-N-(2,3-dichlorophenyl)-3-methylpyrazin-2-amine (6.5 mg, 15 .8 µmol, 15% yield) as its formate salt. ¹ H NMR (400 MHz, methanol-d ₄ ) δ 8.53 (s, 1H, HCOOH), 7.82 (s, 1H), 7.19-7.17 (m, 1H), 7.11- 7.07 (m, 1H), 7.00-6.98 (m, 1H), 4.03-3.99 (m, 2H), 3.34-3.30 (m, 2H), 2, 39 (s, 3H), 1.91-1.84 (m, 4H), 1.46 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₁ Cl ₂ N ₅ : 366.12; the found value is 366.0.

Example 14 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-ethylpyrazin-2-yl)-8-azaspiro[4.5]decan-1 amine

Stage 1. Synthesis of 6-chloro-3-((2,3-dichlorophenyl)thio)pyrazine-2-amine.

To a solution of 2,3-dichlorobenzenethiol (1.3 g, 7.2 mmol, 1.5 eq.) and 3-bromo-6-chloropyrazine-2-amine (1 g, 4.8 mmol, 1 eq.) in dioxane (10 ml) in an inert atmosphere at 20°C was added K3PO4 (1.0 g, 4.8 mmol, 1 equiv.), 1,10-phenanthroline (86 mg, 480 μmol, 0.1 equiv.) and CuI (91 mg, 480 µmol, 0.1 eq.). The resulting mixture was heated to 130°C using microwave radiation for 1.5 h, after which the reaction mixture was concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 6-chloro-3-((2,3-dichlorophenyl)thio)pyrazine-2-amine (400 mg, 1.3 mmol, 27% yield) as a yellow solid.

Stage 2. Synthesis of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-iodopyrazine.

I ₂ ( 795 mg, 3.1 mmol, 1.2 eq.) followed by the addition of t-BuONO (1.2 ml, 10.4 mmol, 4 eq.). The resulting mixture was stirred at 20° C. for 3 hours. After this time, the reaction mixture was quenched with saturated aqueous Na ₂ SO ₃ (15 ml). The resulting mixture was extracted with DCM (3x20 ml) and the combined organic extracts were washed with brine (20 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 5-chloro-2-((2,3-dichlorophenyl)thio)-3-iodopyrazine (400 mg, 958 µmol, 37% yield) as a white solid.

Stage 3. Synthesis of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-vinylpyrazine.

To a solution of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-iodopyrazine (150 mg, 359.3 µmol, 1 eq.) in a mixture of dioxane (3 ml) and H2O (1 ml) at 20 °C was added potassium trifluoro(vinyl)borate (48 mg, 359.3 µmol, 1 eq.), Pd(dppf)Cl ₂ (26.3 mg, 36 µmol, 0.1 eq.) and Na ₂ CO ₃ ( 76.2 mg, 719 µmol, 2 eq.). The resulting mixture was heated to 100°C for 5 h, after which the mixture was cooled and concentrated at

- 114 041617 reduced pressure. The crude residue was purified by silica gel chromatography to give 5-chloro-2-((2,3-dichlorophenyl)thio)-3-vinylpyrazine (80 mg, 252 µmol, 70% yield) as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 8.17 (s, H), 7.53-7.51 (m, 1H), 7.45-7.43 (m,

1H), 7.24-7.22 (m, 1H), 7.02-6.56 (m, 1H), 6.60-6.56 (m, 1H), 5.77-5.70 ( m, 1H). LC-MS (ESI): mass/charge:

[M+N] calc. for C ₁₂ H ₇ Cl ₃ N ₂ S: 316.94; the found value is 316.9.

Stage 4. Synthesis of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-ethylpyrazine.

To a solution of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-vinylpyrazine (95 mg, 299 µmol, 1 eq.) in ethyl acetate (10 ml) was added Pd/C (10 mg), after which the resulting mixture was placed under an atmosphere of H ₂ (15 psi). The mixture was stirred at 20° C. for 1 h after which the mixture was filtered and concentrated to give 5-chloro-2-((2,3-dichlorophenyl)thio)-3-ethylpyrazine (95 mg, crude) as a colorless oil, which was used without further purification.

Step 5. Synthesis of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-ethylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl) -2-methylpropane-2-sulfinamide.

To a solution of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-ethylpyrazine (100 mg, 313 µmol, 1 eq.) in DIPEA (3 ml) and NMP (1 ml) was added at 20°C (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2sulfinamide (121.3 mg, 469 µmol, 1.5 eq.). The mixture was then heated to 120°C for 2 hours. At the end of this time, the mixture was cooled and concentrated under reduced pressure to give crude (R)-N-((R)-8-(5-((2,3-dichlorophenyl )thio)-6-ethylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2methylpropan-2-sulfinamide (150 mg, crude) as a brown oil which was used without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₃₄ Cl ₂ N ₄ OS ₂ : 541.16; the found value is 541.1.

Step 6. Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-ethylpyrazin-2-yl)-8-azaspiro[4.5]decan-1amine.

(R)-8-(5-((2,3-Dichlorophenyl)thio)-6-ethylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to the method in example 1, except that N-((R)-8-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2- methylpropan-2-sulfinamide was replaced by (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-ethylpyrazin-2-yl)-8-azaspiro[4.5] decan-1-yl)-2methylpropan-2-sulfinamide. 1H NMR (400 MHz, chloroform-d) δ 8.47 (s, 1H, HCOOH), 8.12 (s, 1H), 7.347.30 (m, 1H), 7.12-7.08 (m, 1H), 6.67-6.65(m, 1H), 4.44-4.32(m, 2H), 3.23-3.19(m, 2H), 2.83-2.77( m, 2H), 1.90-1.86 (m, 1H), 1.75-1.58 (m, 9H), 1.21-1.17 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₆ Cl ₂ N ₄ S: 437.13; the found value is 437.1.

Example 15 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-phenylpyrazin-2-yl)-8-azaspiro[4.5]decan-1amine

(P)-8-(5-((2,3-Dichlorophenyl)thio)-6-phenylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to the method in example 14, except that potassium trifluoro(vinyl)borate was replaced by phenylboronic acid. (P)-8-(5-((2,3-Dichlorophenyl)thio)-6-phenylpyrazin-2-yl)8-azaspiro[4.5]decan-1-amine was isolated as its formate salt. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.54 (s, 1H, HCOOH), 8.19 (s, 1H), 7.61-7.58 (m, 2H), 7.38-7 .30 (m, 4H), 7.13-7.11 (m, 1H), 7.09-6.89 (m,

1H), 4.43-4.31 (m, 2H), 3.30-3.18 (m, 2H), 3.18-3.13 (m, 1H), 2.16-2.05 ( m, 1H), 1.91-1.52 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₂₆ Cl ₂ N ₄ S: 485.13; the found value is 485.2.

Example 16 Synthesis of azaspiro[4.5]decane-1-amine

(P)-8-(6-cyclopropyl-5-((2,3-dichloropyridin-4-yl)thio)pyrazin-2-yl)-8-

(P)-8-(6-Cyclopropyl-5-((2,3-dichloropyridin-4-yl)thio)pyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to method in example 14, except that 2,3-dichlorobenzenethiol and trifluoro(vinyl)potassium borate were replaced by 2,3-dichloropyridine-4-thiol and cyclopropylboronic acid, respectively. 1H NMR (400 MHz, chloroform-d) δ 8.27 (s, 1H), 8.01-7.29 (m, 2H), 6.52 (d, J=5.39 Hz, 1H), 4 .18 (d, J=9.03 Hz, 2H), 3.16-3.05 (m, 2H), 3.00 (t, J=6.39 Hz, 1H), 2.42-2, 33 (m, 1H), 2.43-2.32 (m, 1H), 2.07 (s, 1H), 1.90-1.77 (m, 2H), 1.69 (d, J= 8.40 Hz, 2H), 1.75-1.59 (m, 3H), 1.55-1.48 (m, 1H), 1.51 (br d, J=13.30 Hz, 1H) , 1.38 (d, J=14.17 Hz, 1H), 1.26-1.21 (m, 1H), 1.04-0.97 (m, 1H), 1.03-0.97

- 115 041617 (m, 1H), 0.93-0.87 (m, 1H), 0.93-0.87 (m, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C21H25CI2N5S:

450.12; found value: 450.2.

Example 17 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-phenylpyrazin-2-yl)-8-azaspiro[4.5]decan-1amine

Stage 1. Synthesis of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-iodopyrazin-2-yl)-8-azaspiro[4.5]decan1-yl) -2-methylpropane-2-sulfinamide.

To a solution of 5-chloro-2-((2,3-dichlorophenyl)thio)-3-iodopyrazine (300 mg, 719 µmol, 1 eq.) in dioxane (4 ml) and DIPEA (4 ml) at 20°C was added (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2sulfinamide (241 mg, 934 µmol, 1.3 eq) and the resulting mixture was heated to 120°C for 3 hours After this time, the mixture was cooled and concentrated. The crude residue was purified by silica gel chromatography to give (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6iodopyrazin-2-yl)-8-azaspiro[4.5] decan-1-yl)-2-methylpropan-2-sulfinamide (200 mg, 313 µmol, 44% yield) as a yellow solid.

Step 2. Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-iodopyrazin-2-yl)-8-azaspiro[4.5]decan-1amine.

(R)-8-(5-((2,3-Dichlorophenyl)thio)-6-phenylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-αmin was synthesized by a method similar to the method in example 1, except that N-((R)-8-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2- methylpropan-2-sulfinamide was replaced by (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-iodopyrazin-2-yl)-8-azaspiro[4.5] decan-1-yl)-2methylpropan-2-sulfinamide.

(R)-8-(5-((2,3-Dichlorophenyl)thio)-6-phenylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-αmin was isolated as its formate salt. ¹ H NMR (400 MHz, methanol-d ₄ ) δ 8.54 (HCOOH s, 1H), 8.11 (s, 1H), 7.45-7.40 (m, 1H), 7.23-7 .16 (m, 1H), 6.96 (dd, J=7.94, 1.32 Hz, 1H), 4.35-4.12 (m, 2H), 3.24-3.10 (m , 2H), 2.28-2.14 (m, 1H), 1.96-1.41 (m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C^CW 534.99; the found value is 535.0.

Example 18 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-iodopyrazin-2-yl)-4-methylpiperidin-4-amine

1-(5-((2,3-Dichlorophenyl)thio)-6-iodopyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 17, except that (R) -2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(4-methylpiperidin-4yl)carbamate. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.13 (s, 1H), 7.44 (dd, J=8.05, 1.43 Hz, 1H), 7.20 (t, J=7 .94 Hz, 1H), 7.04 (dd, J=7.94, 1.32 Hz, 1H), 4.14-4.02 (m, 2H), 3.50-3.36 (m, 2H), 1.86-1.44 (m, 2H), 1.94-1.76 (m, 1H), 1.47 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₇ Cl ₂ IN ₄ S: 494.96; the found value is 495.0.

Example 19 Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-((2,3-dichlorophenyl)thio)pyrazine-2carbonitrile

Synthesis of 6-chloro-3-((2,3-dichlorophenyl)thio)pyrazine-2-carbonitrile.

CuI (73 mg , 384 µmol), 1,10-phenanthroline (69.2 mg, 384 µmol, 202 eq.), K4[Fe(CN) ₆ ] (1.4 g, 3.8 mmol, 202 eq.). The resulting mixture was heated to 120°C for

- 116 041617

hours After this time, the mixture was cooled and poured into water (5 ml). The resulting mixture was extracted with EtOAc (3x5 ml). The combined organic extracts were washed with water (5 ml) and brine (5 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 6-chloro-3-((2,3-dichlorophenyl)thio)pyrazine-2-carbonitrile (320 mg, 1.0 mmol, 52.6% yield) as a yellow solid substances. ¹ H NMR (400 MHz, chloroform-d) δ 8.40 (s, 1H), 7.64-7.40 (m, 2H), 7.327.26 (m, 1H).

6-(4-Amino-4-methylpiperidin-1-yl)-3-((2,3-dichlorophenyl)thio)pyrazine-2-carbonitrile was synthesized by a method similar to that of Example 1, except that N- ((R)-8-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide has been replaced on tert-butyl-(1-(6-cyano-5-((2,3-dichlorophenyl)thio)pyrazin-2-yl)-4-methylpiperidin-4yl)carbamate. ¹ H NMR (400 MHz, methanol^) δ 8.47 (s, 1H), 7.50-7.47 (m, 1H), 7.26-7.20 (m, 2H), 4.22- 4.17 (m, 2H), 1.92-1.86 (m, 4H), 1.50 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C17H17Q2N5S: 394.06; the found value is 394.1.

Example 20 Synthesis of (R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazine-2carbonitrile

Cl CN

(R)-6-(1-Amino-8-azaspiro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazine-2-carbonitrile was synthesized by a method similar to that of Example 19 , except that tert-butyl(4-methylpiperidin-4-yl)carbamate was replaced by (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan2 -sulfinamide.

(R)-6-(1-Amino-8-azaspuro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazine-2-carbonitrile was isolated as its formate salt. ¹ H NMR (400 MHz, methanol-d ₄ ) δ 8.5 (s, 1H, HCOOH), 8.43 (s, 1H), 7.49-7.46 (m, 1H), 7.25- 7.21(m, 1H), 7.17-7.16(m, 1H), 4.38-4.26(m, 2H), 3.25-3.20(m, 2H), 2, 24-2.22(m, 1H), 1.89-1.57(m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₁ Cl ₂ N ₅ S: 434.09; the found value is 434.1.

Example 21 Synthesis of (R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazin-2ol.

Stage 1. Synthesis of 5-bromo-3-((4-methoxybenzyl)oxy)pyrazine-2-amine.

To a solution of 3,5-dibromopyrazine-2-amine (15.00 g, 59.31 mmol, 1.0 eq.) and (4-methoxyphenyl)methanol (11.07 ml, 88.97 mmol, 1.5 eq. .) in dioxane (70 ml) was added KOt-Bu (9.98 g, 88.97 mmol, 1.5 eq.) at 25°C. The mixture was stirred at 100° C. for 2 hours. After this time, the reaction mixture was quenched by adding water (20 ml) and the resulting biphasic mixture was extracted with EtOAc (3x20 ml). The combined organic layers were washed with brine (50 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 5-bromo-3-((4methoxybenzyl)oxy)pyrazine-2-amine (12 g, 38.69 mmol, 65% yield) as a red solid. ¹ H NMR (400 MHz, chloroform-d) δ 7.67 (s, 1H), 7.42-7.40 (m, 2H), 7.33-7.28 (m, 1H), 6.96 -6.91 (m, 3H), 5.34 (s, 2H), 3.85 (s, 3H).

Stage 2. Synthesis of 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine.

t-BuONO (7.64 ml, 64.5 mmol, 4 eq.) and I ₂ (4.91 g, 19.3 mmol, 1.2 eq.). The mixture was stirred at 25°C for 3 hours Then the reaction mixture was diluted with saturated aqueous Na ₂ S ₂ O ₃ (10 ml) and was extracted with CH ₂ Cl ₂ (3x10 ml). The combined organic layers were washed with brine (30 ml), dried over Na2SO4, filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine (2.30 g, 5.46 mmol, 33.9% yield) as white

- 117 041617 solids. E NMR (400 MHz, chloroform-d) 88.09 (s, 1H), 7.46 (d, J=8.31 Hz, 2H), 7.30-7.28 (m,

1H), 6.95 (d, J=8.44 Hz, 2H), 5.43-5.39 (m, 2H), 3.85 (s, 3H).

Stage 3. Synthesis of 5-bromo-2-((2,3-dichlorophenyl)thio)-3-((4-methoxybenzyl)oxy)pyrazine.

To a solution of 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine (2.30 g, 5.46 mmol, 1 eq.) and 2,3-dichlorobenzenethiol (978 mg, 5.46 mmol, 1 equiv.) in dioxane (20 ml) at 25°C was added CuI (104 mg, 546 µmol, 0.10 equiv.), K ₃ PO ₄ (1.39 g, 6.55 mmol, 1.2 equiv.) and 1,10-phenanthroline (98.4 mg, 546 µmol, 0.10 eq.). The resulting mixture was then heated to 70° C. and stirred for 3 hours. After this time, the reaction mixture was diluted with H ₂ O (10 ml) and the resulting biphasic mixture was extracted with EtOAc (3x10 ml). The combined organic extracts were washed with brine (30 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 5-bromo-2-((2,3-dichlorophenyl)thio)-3-((4-methoxybenzyl)oxy)pyrazine (1.80 g, 3.81 mmol, yield 69.8%) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 7.92 (s, 1H), 7.52-7.47 (m, 2H), 7.41-7.39 (m, 2H), 7.21- 7.17 (m, 1H), 6.92-6.90 (m, 2H), 5.39 (s, 2H), 3.81 (s, 3H).

Step 4. Synthesis of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-((4-methoxybenzyl)oxy)pyrazin-2-yl)8-azaspiro [4.5]decan-1-yl)-2-methylpropan-2-sulfinamide.

To a solution of 5-bromo-2-((2,3-dichlorophenyl)thio)-3-((4-methoxybenzyl)oxy)pyrazine (1.00 g, 2.12 mmol, 1 eq) and N-(( 4R)-8-azaspiro[4.5]decan-4-yl)-2-methylpropan-2-sulfinamide (822 mg, 3.18 mmol, 1.5 eq) in toluene (10 mL) NaO was added at 25°C -t-Bu (437 mg, 4.24 mmol, 2 eq.), [1-(2diphenylphosphanyl-1-naphthyl)-2-naphthyl]diphenylphosphane (132 mg, 212 µmol, 0.10 eq.) and Pd ₂ (dba) ₃ (97.1 mg, 106 µmol, 0.05 eq.). The resulting mixture was heated to 130° C. and stirred for 3 h under microwave radiation. After this time, the reaction mixture was cooled and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-((4-methoxybenzyl)oxy)pyrazin2-yl) -8-azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide (700 mg, 1.08 mmol, 50.8% yield) as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 7.70 (s, 1H), 7.24 (dd, J=8.01, 1.16 Hz, 1H), 7.18 (d, J=8, 56 Hz, 2H), 6.97 (t, J=8.01 Hz, 1H), 6.84-6.79 (m, 3H), 5.28 (s, 2H), 4.22-4, 19 (m, 2H), 3.82 (s, 3H), 3.41-3.36 (m, 1H), 3.22-3.21 (m, 1H), 3.15-3.04 ( m, 2H), 3.15-3.04 (m, 2H), 2.19-2.11 (m, 1H), 1.391.19 (m, 10H), 1.30-1.26 (m, 1H), 1.24 (s, 9H).

Step 5. Synthesis of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-hydroxypyrazin-2-yl)-8azaspiro[4.5]decan-1-yl) -2-methylpropane-2-sulfinamide.

(R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-((4-methoxybenzyl)oxu)nirazin-2-yl)-8azaspiro[4.5]decane solution -1-yl)-2-methylpropan-2-sulfinamide (300 mg, 462 μmol, 1 eq.) in TFA (10 ml) at 25°C was stirred for 1 h before it was concentrated under reduced pressure. The crude material thus obtained was used in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₃ H ₃₀ Cl ₂ N ₄ O ₂ S ₂ : 529.12; the found value is 529.0.

Step 6. Synthesis of (R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazin-2ol.

(R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-hydroxynirazin-2-yl)-8-azacniro[4.5]decan-1yl)-2- solution methylpropane-2-sulfinamide (300 mg, 567 μmol, 1 eq.) in HCl/MeOH (10 ml) at 25° C. was stirred for 0.5 h. After this time, the reaction mixture was concentrated. The crude residue thus obtained was purified by preparative HPLC to give (R)-6-(1amino-8-azaspiro[4.5]decan-8-yl)-3-((2,3-dichlorophenyl)thio)pyrazin-2- ol (150 mg, 353 µmol, 62.2% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 8.39 (s, 1H), 7.58 (s, 1H), 7.25-7.22 (m, 1H), 7.05-7.01 ( m, 1H), 6.69-6.67 (m, 1H), 4.23-4.141 (m, 2H), 3.18-3.06 (m, 3H), 1.84-1.83 ( m, 1H), 1.81-1.48 (m, 9H).

Example 22 Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-((2,3-dichlorophenyl)thio)pyrazin-2-ol

6-(4-Amino-4-methylpiperidin-1-yl)-3-((2,3-dichlorophenyl)thio)pyrazin-2-ol was synthesized by a method similar to that of Example 21, except that (R )-2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(4-methylpiperidin-4yl)carbamate. 1H NMR (400 MHz, chloroform-d) δ 7.79 (s, 1H), 7.31-7.29 (m, 1H), 7.11-7.07 (m, 1H), 6.836.81 ( m, 1H), 4.12-4.08 (m, 2H), 3.41-3.34 (m, 2H), 1.84-1.81 (m, 4H), 1.44 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ Cl ₂ N ₄ OS: 385.06, found value 3 85.0.

- 118 041617

Example 23 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1 amine

Stage 1. Synthesis of 5-chloro-2-(2,3-dichlorophenyl)-3-methylpyrazine.

To a degassed solution of 2-bromo-5-chloro-3-methylpyrazine (400 mg, 1.93 mmol, 1 eq.) and (2,3dichlorophenyl)boronic acid (367.92 mg, 1.93 mmol, 1 eq.) Pd(dppf)Cl ₂ -DCM (157.45 mg, 192.81 µmol, 0.1 eq.) was added to MeCN (60 ml) and H2O (6 ml) under an inert atmosphere. The reaction mixture was stirred in a microwave oven at 120° C. for 2 hours. At the end of this time, TLC (2:1 petroleum ether: ethyl acetate, Rf=0.49) indicated complete consumption of the bromopyrazine starting material. Then the reaction mixture was poured into water (500 ml) and the resulting aqueous phase was extracted with ethyl acetate (3x200 ml). The combined organic extracts were then washed with brine (500 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give a crude residue which was purified by silica gel chromatography to give 5-chloro-2-(2,3 -dichlorophenyl)-3-methylpyrazine (800 mg, 2.92 mmol, 75.6% yield) as a yellow solid. 1H NMR (400 MHz, chloroform-d): δ 8.53 (s, 1H), 7.597.62 (m, 1H), 7.35-7.39 (m, 1H), 7.25-7.29 (m, 1H), 2.44 (s, 3H).

Stage 2. Synthesis of N-((R)-8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)2-methylpropan-2 -sulfinamide.

A mixture of 5-chloro-2-(2,3-dichlorophenyl)-3-methylpyrazine (250 mg, 913.91 µmol, 1 eq) and 2-methyl-N((R)-8-azaspiro[4.5]decan- 1-yl)propan-2-sulfinamide (259.79 mg, 1.01 mmol, 1.1 eq.) in DIPEA (1.18 g, 9.14 mmol, 1.60 ml, 10 eq.) was stirred in inert atmosphere at 95° C. for 2 hours. After this time, LC-MS showed complete consumption of the starting material, which is chlorpyrazine, and the presence of a peak corresponding to the desired product. Then the reaction mixture was cooled to 20°C and poured into water (10 ml). The resulting aqueous phase was extracted with ethyl acetate (2x5 ml). The combined organic extracts were washed with brine (20 ml), dried over anhydrous Na ₂ SO ₄ and concentrated to give N-((R)-8-(5-(2,3-dichlorophenyl)-6methylpyrazin-2-yl)-8 -azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide (250 mg, 504.53 µmol, 27.6% yield) as a yellow oil. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₄ H ₃₂ Cl ₂ N ₄ OS: 495.17; the found value is 495.1.

Step 3. Synthesis of (R)-8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine.

A mixture of N-((R)-8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2methylpropan-2-sulfinamide (250 mg, 504.53 µmol, 1 eq.) in HCl-MeOH (4 M, 25 ml, 198.2 eq.) was stirred under an inert atmosphere at 20° C. for 1 h. The mixture was then concentrated under reduced pressure and purified with by preparative HPLC to give (R)-8-(5-(2,3-dichlorophenyl)-6methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine (150 mg, 383.30 µmol, yield 76%) as a yellow oil. 1H NMR (400 MHz, methanol-d4): δ 8.07 (s, 1H), 7.64 (d, J=16 Hz 1H), 7.43 (m, 1H), 7.33 (d, J =16 Hz, 1H), 4.41-4.33 (m, 2H), 3.27-3.17 (m, 3H), 2.23-2.21 (m, 1H), 2.21 ( s, 3H), 1.93-1.59 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₄ Cl ₂ N ₄ : 391.14; the found value is 391.1.

Example 24 Synthesis of 1-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

-(5-(2,3-Dichlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 23, except that 2-methyl-N-( (R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(4-methylpiperidin-4yl)carbamate. 1H NMR (400 MHz, methanol-d4): δ 8.19 (s, 1H), 7.67 (m 1H), 7.42-7.46 (m, 1H), 7.35 (d, J= 12

- 119 041617

Hz 1H), 4.27-4.23 (m, 2H), 3.49-3.45 (m, 2H), 2.25 (s, 3H), 1.93-1.91 (m, 4H ), 1.52 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ Cl ₂ N ₄ : 351.11; the found value is 351.0.

Example 25 Synthesis of 1-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-3-methylazetidine-3-amine

1-(5-(2,3-Dichlorophenyl)-6-methylpyrazin-2-yl)-3-methylazetidine-3-amine was synthesized by a method similar to that of Example 23, except that 2-methyl-N- ((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(3-methylazetidin-3yl)carbamate. 1-(5-(2,3-Dichlorophenyl)-6-methylpyrazin-2-yl)-3-methylazetidine-3-amine was isolated as its formate salt after HPLC purification. 1 H NMR (500 MHz, DMSO-d ₆ ) δ 8.25 (s, 1H), 7.76 (s, 1H), 7.70 (dd, J=8.0, 1.6 Hz, 1H), 7.47-7.43(m, 1H), 7.35(dd, J=7.6, 1.6Hz, 1H), 3.93-3.88(m, 2H), 3.86( d, J=8, 2Hz, 2H), 2.12(s, 3H), 1.44(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₅ H ₁₆ Cl ₂ N ₄ : 323.08; the found value is 323.38.

Example 26 Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazine-2 carbonitrile

Stage 1. Synthesis of 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-amine.

To a solution of 3-bromo-6-chloropyrazine-2-amine (30 g, 144 mmol, 1 eq.) in dioxane (360 ml) was added (2,3-dichlorophenyl)boronic acid (33 g, 173 mmol, 1.2 eq.), solution of K ₃ PO ₄ (92 g, 432 mmol, 3.0 eq.) in H2O (36 ml) and Pd(dppf)Cl ₂ (11 g, 14.4 mmol, 0.1 eq.) . The reaction mixture was heated to 80°C and stirred for 16 h, after which the solution was concentrated under reduced pressure. The residue was purified by silica gel chromatography to give 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2amine (25 g, 91 mmol, 63% yield) as a yellow solid. 1H NMR (400 MHz, DMSO-d ₆ ) δ 7.87-7.82 (m, 1H), 7.73 (dd, J=7.94, 1.54 Hz, 1H), 7.50-7 .44 (m, 1H), 7.41-7.36 (m, 1H), 6.69 (br s, 2H).

Stage 2. Synthesis of 5-chloro-2-(2,3-dichlorophenyl)-3-iodopyrazine.

To a solution of 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-amine (15 g, 54 mmol, 1 eq.) in CH2I2 (150 ml) at 25 219 mmol, 4 eq.) and I ₂ (13 ml, 66 mmol, 1.2 eq.). The reaction mixture was stirred for 16 h before it was extinguished by adding an aqueous solution of Na ₂ S ₂ O ₃ (150 ml) and was extracted with DCM (2x100 ml). The combined organic extracts were then washed with brine (100 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The residue was then purified by silica gel chromatography to give 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile (9.0 g, 23 mmol, 43% yield) as a yellow solid. LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₀ H ₄ Cl ₃ IN ₂ : 384.85; the found value is 384.8.

Stage 3. Synthesis of 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile.

1,10-phenanthroline ( 42 mg, 234 µmol, 0.2 eq.), CuI (45 mg, 234 µmol, 0.2 eq.), potassium ferrocyanide (862 mg, 2.3 mmol, 2 eq.). The mixture was then further heated to 120° C. and stirred for 4 hours. At the end of this time, the reaction mixture was concentrated under reduced pressure, and the crude residue thus obtained was purified by silica gel chromatography to give 6-chloro-3-(2,3- dichlorophenyl)pyrazine-2-carbonitrile (170 mg, 597 µmol, 51% yield) as a white solid. 1 H NMR (400 MHz, methanol-d ₄ ) δ 9.04 (s, 1H), 7.80-7.77 (m, 1H), 7.557.49 (m, 2H).

Step 4. Synthesis of tert-butyl-(1-(6-cyano-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4-methylpiperidin-4yl)carbamate.

A mixture of 6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile (50 mg, 176 µmol, 1 eq) and tert-butyl (4-methylpiperidin-4-yl) carbamate (56.5 mg, 264 µmol, 1.5 eq.) in dioxane (1 ml) and DIPEA (1 ml) was heated to 120°C and stirred for 2 h. The mixture was then concentrated under reduced pressure to obtain tert-butyl-(1-(6 -cyano-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (80 mg, crude) as a yellow oil, which was directly applied to the

- 120 041617 blowing stage without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C22H25C12N5O2:

462.14; the found value is 462.0.

Step 5. Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile.

Solution of tert-butyl-(1-(6-cyano-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (80 mg, 173 µmol, 1 eq.) in HCl/ MeOH (4 M, 3 ml) was stirred at 20° C. for 1 h. At the end of this time, the mixture was concentrated under reduced pressure and the crude residue was purified by preparative HPLC to give 6-(4-amino-4-methylpiperidine-1- yl)-3-(2,3dichlorophenyl)pyrazine-2-carbonitrile (9.1 mg, 21 µmol, 12% yield, 94% purity) as a yellow solid. LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₁₈ Cl ₂ N ₅ : 362.09; found value 362.0; RT=0.992 min. 6-(4-Amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile was isolated as its formate salt. 1H NMR (400 MHz, chloroform-d) δ 8.59 (s, 1H), 8.53 (s, 1H, HCOOH), 7.71-7.68 (m, 1H), 7.47-7, 44 (m, 2H), 4.23-4.19 (m, 2H), 3.57-3.50 (m, 2H), 1.92-1.83 (m, 4H), 1.49 ( s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₁₇ Cl ₂ N ₅ : 362.09; the found value is 362.1.

Example 27 Synthesis of N)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2carbonitrile.

(R)-6-(1-Amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2-αcarbonitrile was synthesized by a method similar to that of Example 26, except that tert-butyl-(4methylpiperidin-4-yl)carbamate was replaced by (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2sulfinamide.

(R)-6-(1-Amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile was isolated as its formate salt. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₁ Cl ₂ N ₅ : 402.12; the found value is 402.2.

Example 28 Synthesis of (1-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4yl)methanamine

Me (1-(5-(2,3-Dichlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-yl)methanamine was synthesized by a method similar to that of Example 23, except that 2- methyl N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl((4-methylpiperidin-4-yl)methyl)carbamate. 1H NMR (500 MHz, DMSO-d6) δ 8.28 (s, 1H), 7.82 (d, J=0.7 Hz, 1H), 7.51 (d, J=7.7 Hz, 1H ), 7.42 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.65 (dd, J=8.1, 1.4 Hz, 1H), 4.11-4.00 (m, 1H), 2.78-2.56 (m, 4H), 2.35 (d, J=2.4 Hz, 6H), 1.97 (dddd, J=21.8, 10.9, 7.7, 5.0 Hz, 2H), 1.80-1.69 (m, 2H), 1.63 (dt, J=10 .7, 8.8 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ : 365.12; the found value is 365.2.

Example 29 Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-ol

Step 1. Synthesis of (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate.

To a solution of (R)-8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine (4.0 g, 10 mmol, 1 eq. .) in DCM (3 ml) at 25°C was added Boc ₂ O (3.4 g, 15 mmol, 1.5 eq.) and Et ₃ N (3.1 g, 30

- 121 041617 mmol, 3 eq.). The mixture was stirred for 2 hours before being concentrated under reduced pressure. The crude residue was then purified by silica gel chromatography to give (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan- 1-yl)carbamate (2.3 g, 4.6 mmol, 46% yield) as a colorless oil. 1H NMR (400 MHz, chloroform-d) δ 7.99 (s, 1H), 7.49 (dd, J=7.72, 1.98 Hz, 1H), 7.29-7.26 (m, 1H), 7.25-7.21 (m, 1H), 4.30-4.07 (m, 2H), 3.20-3.03 (m, 2H), 2.23 (s, 3H) , 2.15-2.05 (m, 1H), 1.84-1.56 (m, 10H), 1.43 (s, 9H).

Stage 2. Synthesis of (R)-tert-butyl-(8-(3-bromo-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate .

To a solution of (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (2.3 g, 4.7 mmol, 1 eq.) in DCM (15 ml) at 0°C was added NBS (1.2 g, 7.0 mmol, 1.5 eq.). The mixture was then heated to 25°C and stirred for 2 h, after which the reaction mixture was concentrated under reduced pressure. The crude residue was then purified by silica gel chromatography to give (R)-tert-butyl-(8-(3-bromo-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5] decan-1-yl)carbamate (1.3 g, 2.3 mmol, 48.7% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) δ 7.52 (dd, J=7.39, 2.32 Hz, 1H), 7.28-7.26 (m, 2H), 4.45 (m, 1H), 3.91-3.85 (m, 3H), 3.12-3.05 (m, 2H), 2.24 (s, 3H), 2.16-2.01 (m, 2H) , 1.92 (m, 1H), 1.82-1.63 (m, 5H), 1.55 (s, 9H).

Step 3. Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin2-ol.

Solution of (R)-tert-butyl-(8-(3-bromo-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (50, 0 mg, 87.7 μmol, 1 eq.) in HCl/EtOAc (4 M, 3 ml) was stirred at 25°C for 0.5 h, after which the reaction mixture was concentrated under reduced pressure. The residue was purified by preparative HPLC to give (R)-3-(1-amino-8-azaspiro[4.5]decan-8yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-ol (20, 00 mg, 39.37 µmol, 39.80% yield as a white solid. 1H NMR (400 MHz, DMSO-d6) δ 7.73-7.71 (m, 1H), 7.44-7.39 (m, 2H), 4.55-4.51 (m, 2H), 3.08-2.98 (m, 1H), 1.82-1.71 (m, 2H), 1.69 (s, 3H), 1.65-1.35 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂ 4Cl ₂ N4O: 407.13; the found value is 407.9.

Example 30 Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine-2-carboxamide

Stage 1. Synthesis of (R)-methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin-2 -carboxylate.

To a solution of (R)-tert-butyl-(8-(3-bromo-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (1 0 g, 1.7 mmol, 1 eq.) in THF (2.0 ml) and MeOH (2.0 ml) at 25°C was added Et ₃ N (729 μl, 5.3 mmol, 3.1 eq. .) and Pd(dppf)Cl ₂ (128 mg, 0.17 mmol, 0.1 eq.). The suspension was degassed and purged with CO three times and then the mixture was sealed under CO (50 psi), heated to 50° C. and stirred for 2 hours. After this time, the reaction mixture was cooled and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give the compound which is (R)methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2 ,3-dichlorophenyl)-5methylpyrazine-2-carboxylate (900.0 mg, 1.6 mmol, 93.6% yield), as a green solid. 1H NMR (400 MHz, chloroform-d) δ 7.49 (dd, J=6.84, 2.87 Hz, 1H), 7.31-7.27 (m, 2H), 3.93 (s, 3H), 3.85-3.75 (m, 2H), 3.20 (m, 2H), 2.27 (s, 3H), 2.4-2.04 (m, 1H), 1.87 -1.58 (m, 8H), 1.44 (s, 9H).

Stage 2. Synthesis of (R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin-2-carboxylic acids.

To a solution of methyl(R)-methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin-2- carboxylate (1.0 g, 1.8 mmol, 1 eq.) in a mixture of THF (1 ml), MeOH (3 ml) and H ₂ O (1 ml) at 25°C was added LiOH-H ₂ O (229 mg , 5.4 mmol, 3 eq.). The resulting mixture was heated to 40°C and stirred for 3 h, after which the reaction mixture was concentrated under reduced pressure. The crude residue was diluted with H ₂ O (10 ml) and extracted with MTBE (20 ml). Then the aqueous phase was adjusted to pH 4 with aqueous HCl (1 M) and was extracted with ethyl acetate (3x20 ml). The combined ethyl acetate extracts were washed with brine (30 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The he-122 041617 purified residue was purified by silica gel chromatography to give (R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3- dichlorophenyl)-5-methylpyrazine-2-carboxylic acid (900 mg, 1.6 mmol, 92% yield) as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 7.57-7.55 (m, 1H), 7.35-7.27 (m, 2H), 4.05-3.91 (m, 2H), 3.79-3.77 (m, 1H), 3.36-3.27 (m, 2H), 2.34 (s, 3H), 2.09 (m, 2H), 1.72-1, 56 (m, 9H), 1.44 (s, 11H).

Stage 3. Synthesis of (R)-tert-butyl-(8-(3-carbamoyl-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate .

To a solution of (R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)5-methylpyrazine-2-carboxylic acid (50 mg, 93 µmol, 1 eq.) in DMF (1.0 ml) at 25°C was added PyBOP (97 mg, 186 µmol, 2 eq.), NH4OAC (18 mg, 233 µmol, 2.5 eq. ) and Et ₃ N (26 μl, 187 μmol, 2 eq.). The mixture was then heated to 80° C. and stirred for 3 hours. After this time, the reaction mixture was diluted with water (5 ml) and extracted with ethyl acetate (3x10 ml). The combined organic extracts were washed with brine (20 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give (R)-tert-butyl-(8-(3-carbamoyl-5-(2,3-dichlorophenyl )-6methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (40 mg, crude) as a red oil.

Step 4. Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine2-carboxamide.

A mixture of (R)-tert-butyl-(8-(3-carbamoyl-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (40, 00 mg, 74.84 μmol, 1 eq) in HCl/ethyl acetate (4 M, 5 ml) was stirred at 25° C. for 0.5 h after which the reaction mixture was concentrated under reduced pressure. The crude residue was adjusted to pH 7 with saturated aqueous Na ₂ HCO ₃ (10 ml) and the resulting aqueous solution was extracted with ethyl acetate (3x10 ml). The combined organic extracts were washed with brine (20 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by preparative HPLC to give (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine-2-carboxamide (3 .00 mg, 6.91 µmol, 9.23% yield as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 7.55-7.53 (m, 1H), 7.33-7.29 (m, 2H), 3.98-3.88 (m, 2H), 3.17-3.06 (m, 3H), 2.34 (s, 3H), 1.83-1.78 (m, 1H), 1.74-1.43 (s, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₅ Cl ₂ N ₅ O: 434.14; the found value is 433.9.

Example 31 Synthesis of (R)-8-(3-amino-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-amine

Stage 1. Synthesis of tert-butyl-(R)-(8-(3-((tert-butoxycarbonyl)amino)-5-(2,3-dichlorophenyl)-6methylpyrazin-2-yl)-8-azaspiro[4.5] decan-1-yl)carbamate.

To a solution of (R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazine-2-carboxylic acid ( 80 mg, 149 µmol, 1 eq.) in toluene at 25°C (3.0 ml), DPPA (35 µl, 164 µmol, 1.1 eq.), Et ₃ N (41 µl, 299 µmol, 2 eq.) and t-BuOH (142 μl, 1.5 mmol, 10 eq.). The mixture was then heated to 120° C. and stirred for 3 hours. After this time, the reaction mixture was cooled and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give t-butyl-(R)(8-(3-((t-butoxycarbonyl)amino)-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl) -8-azaspiro[4.5]decan-1yl)carbamate (60 mg, 98 µmol, 66% yield) as a white solid. 1H NMR (400 MHz, chloroform-d) 7.49-7.47 (m, 1H), 7.28-7.21 (m, 3H), 4.51 (s, 2H), 4.45-4 .43 (m, 1H), 3.77-3.75 (m, 1H), 3.51-3.46 (m, 2H), 2.92-2.87 (m, 2H), 2.16 (s, 3H), 2.07 (m, 1H), 1.84-1.61 (m, 9H), 1.46-1.40 (s, 18H).

Step 2. Synthesis of (R)-8-(3-amino-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan1-amine.

(R)-8-(3-Amino-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to that for 5- (4-amino-4-methylpiperidin-1-yl)-N-(2,3dichlorophenyl)-3-methylpyrazin-2-amine. 1H NMR (400 MHz, chloroform-d) δ 7.52-7.50 (m, 1H), 7.29-7.27 (m, 1H), 7.19-7.17 (m, 1H), 3.44-3.39 (m, 2H), 3.17-3.13 (m, 1H), 2.90-2.87 (m, 2H), 2.11 (m, 1H), 2. 00 (s, 3h), 1.81-1.45 (m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₅ Cl ₂ N ₅ : 406.15; found value 40 6.0.

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Example 32.

Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl)methanol.

Step 1. Synthesis of (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)8-azaspiro[4.5]decan-1- yl) carbamate.

To a solution of methyl-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazine-2-carboxylate (50 mg, 90 μmol, 1 eq.) in THF (3 ml) at 0°C in an inert atmosphere was added LiBH ₄ (2 M, 91 μl, 180 μmol, 2 eq.). The resulting mixture was stirred at 0° C. for 1 h before being quenched by the addition of H ₂ O (3 ml). The resulting biphasic mixture was extracted with ethyl acetate (3x5 ml). The combined organic layers were washed with brine (10 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-3- (hydroxymethyl)-6methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (50 mg, crude) as a yellow oil. The crude product was used in the next step without further purification.

Step 2 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin2-yl)methanol.

A solution of (R)-tert-butyl-(8-(5-(2,3-dichlorophenyl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate ( 50.0 mg, 95.9 μmol, 1 eq.) in HCl/EtOAc (4 M, 3.0 ml) at 25° C. was stirred for 0.5 h. After this time, the reaction mixture was concentrated under reduced pressure. The residue was purified by preparative HPLC to give (R)-(3-(1-amino-8azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)methanol (18.0 mg, 42.7 µmol, 44.6% yield) as a white solid. 1H NMR (400 MHz, methanol-d ₄ ) δ 7.61 (dd, J=7.94, 1.32 Hz, 1H), 7.44-7.36 (m, 1H), 7.36-7 .30 (m, 1H), 4.67 (s, 2H), 3.76-3.67 (m, 2H), 3.23 (m, 1H), 3.11 (m, 2H), 2, 25 (s, 3h), 2.17 (m, 1H), 1.93-1.49 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₆ Cl ₂ N ₄ O: 421.15; the found value is 421.2.

Example 33 Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2yl)methanol

(3-(4-Amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)methanol was synthesized by a method similar to that of Example 29, Example 30 and Example 32, except that Ίret-butyl-(R)-(8-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate was replaced by tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin4-yl)carbamate. 1H NMR (400 MHz, methanol-04) δ 7.66 (dd, J=8.01, 1.65 Hz, 1H), 7, 47-7, 41 (m, 1H), 7.39-7, 34 (m, 1H), 4.70 (s, 2H), 3.76 (dt, J=13.94, 4.10 Hz, 2H), 3.40-3.32 (m, 2H), 2 .31-2.24 (m, 3H), 2.08-1.90 (m, 4H), 1.50 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ O: 381.12; the found value is 381.1.

Example 34 Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine-2-carbonitrile

Step 1. Synthesis of (R)-tert-butyl-(8-(3-cyano-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8 azaspiro[4.5]decan-1-yl) carbamate.

To a solution of (R)-tert-butyl-(8-(3-bromo-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (30 mg, 52 µmol, 1 eq.) in DMF (1.0 ml) at 25°C was added CuCN (9.4 mg, 105 µmol, 2 eq.). The mixture was heated to 120°C and stirred for 2 h, after which the reaction mixture was cooled to 25°C and diluted with H ₂ O (3 ml). The resulting biphasic mixture was extracted with ethyl acetate (3x3 ml). The combined organic extracts were washed with brine (5 ml), dried over Na2SO4, filtered and concentrated under reduced pressure. The crude residue was purified by preparative TLC to give (R)-tert-butyl(8-(3-cyano-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decane -1-yl)carbamate (20 mg, 39 µmol, 7 3% yield) as a yellow oil.

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Stage 2. Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine2-carbonitrile.

Solution of (R)-tert-butyl-(8-(3-cyano-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (30, 0 mg, 58.1 μmol, 1 eq.) in HCl/EtOAc (4 M, 3 mL) was stirred at 25° C. for 0.5 h after which the reaction mixture was concentrated under reduced pressure. The crude residue was purified by preparative HPLC to give (R)-3-(1-amino-8azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carbonitrile (12 .0 mg, 28.8 µmol, 49.6% yield as a yellow solid. ¹ H NMR (400 MHz, methanol-d ₄ ) δ 8.47 (s, 1H), 7.36 (m, 1H), 7.34 (m, 1H), 7.28 (m, 1H), 4 .52-4.38 (m, 2H), 3.31-3.23 (m, 2H), 2.25 (s, 3H), 2.20 (m, 1H), 1.85-1.51 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₃ Cl ₂ N ₅ : 416.13; the found value is 416.2.

Example 35 Synthesis of methyl-(R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine-2-carboxylate.

(R)-3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate was synthesized by a method similar to that of Example 30 ¹ H NMR (400 MHz, chloroform-d) δ 7.56-7.59 (m, 1H), 7.29-7.29 (m, 1H), 7.27-7.29 (m, 1H ), 3.83-3.90 (m, 5H), 3.11-3.17 (m, 4H), 2.19 (s, 3H), 2.13-2.18 (m, 1H), 1.46-1.84 (m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₆ Cl ₂ N4O ₂ : 449.14; found value 4 49.2.

Example 36 Synthesis of methyl-6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazin-2-ol

Stage 1. Synthesis of 3-(benzyloxy)-5-bromopyrazine-2-amine.

A suspension of NaH (427.1 mg, 17.79 mmol, 1.5 eq.) in dry THF (30 ml) at 0°C was stirred for 10 min before benzyl alcohol (1.85 ml, 17 79 mmol, 1.5 eq) and the mixture was stirred for 30 minutes. At the end of this time, 3,5-dibromopyrazin-2-amine (3.00 g, 11.86 mmol, 1 eq) was added and the reaction mixture was heated to reflux and stirred for 10 h. The mixture was then cooled to 25°C and the residue was poured into ice water (50 ml). Then the aqueous phase was extracted with ethyl acetate (3x20 ml). The combined organic phases were washed with brine (2x30 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 3-(benzyloxy)-5-bromopyrazine-2-amine (3.30 g, 11.78 mmol, 99.33% yield) as a yellow oil.

Stage 2. Synthesis of 3-(benzyloxy)-5-bromo-2-iodopyrazine.

To a solution of 3-(benzyloxy)-5-bromopyrazine-2-amine (3.30 g, 11.78 mmol, 1 eq.) in CH ₂ I ₂ (30 ml) was added tert-butyl nitrite (5.59 ml, 47 .12 mmol, 4 eq.) and I ₂ (3.59 g, 14.14 mmol, 1.2 eq.). The reaction mixture was then stirred at 25°C for 16 h, after which the reaction mixture was quenched by adding an aqueous solution of Na ₂ S ₂ O ₃ (150 ml) and then was extracted with DCM (2x100 ml). The combined organic extracts were washed with brine (100 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 3-(benzyloxy)-5-bromo-2-iodopyrazine (1.90 g, 4.86 mmol, 41.25% yield) as a yellow solid. ¹ H NMR (400 MHz, chloroform-d) δ 8.08 (s, 1H), 7.51-7.32 (m, 6H), 5.45 (s, 2H).

Stage 3. Synthesis of 3-(benzyloxy)-5-bromo-2-(2,3-dichlorophenyl)pyrazine.

To a solution of 3-(benzyloxy)-5-bromo-2-(2,3-dichlorophenyl)pyrazine (1.90 g, 4.86 mmol, 1 eq) in toluene (40 mL) ,3-dichlorophenyl)boronic acid (1.39 g, 7.29 mmol, 1.5 eq.), a solution of Na ₂ CO ₃ in methanol (2 M, 7.29 ml, 3 eq.), and Pd(PPh ₃ ) ₄ (786.1 mg, 680.4 µmol, 0.14 eq.). The reaction mixture was then heated to 60° C. and stirred for 16 hours. The reaction mixture was filtered and concentrated. The residue was purified by silica gel chromatography to give 3-125041617(benzyloxy)-5-bromo-2-(2,3-dichlorophenyl)pyrazine (600 mg, 1.46 mmol, 15% yield) as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 8.35 (s, 1H), 7.54 (dd, J=6.17, 3.53 Hz, 1H), 7.397.27 (m, 7H), 5 .43 (s, 2H).

Step 4. Synthesis of tert-butyl-(1-(6-(benzyloxy)-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4methylpiperidin-4-yl)carbamate.

To a solution of 3-(benzyloxy)-5-bromo-2-(2,3-dichlorophenyl)pyrazine (90.0 mg, 220 µmol, 1 eq.) in toluene (1 ml) was added tert-butyl-(4-methylpiperidine -4-yl)carbamate (705 mg, 329 µmol, 1.5 eq.), NaOt-Bu (42.2 mg, 439 µmol, 2 eq.), [1-(2-diphenylphosphanyl-1-naphthyl)- 2-naphthyl]diphenylphosphane (137 mg, 219 µmol, 1 eq) and Pd ₂ (dba) ₃ (10.0 mg, 11.0 µmol, 0.05 eq). The reaction mixture was then heated to 90° C. and stirred for 1 hour. The reaction mixture was then filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give tert-butyl-(1-(6-(benzyloxy)-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate (100 mg, 184 µmol, 83.8% yield as a white solid.

Step 5. Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazin-2-ol.

A mixture of tert-butyl-(1-(6-(benzyloxy)-5-(2,3-dichlorophenyl)pyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (100 mg, 184 µmol, 1 eq) in HCl (2 ml) was heated to 100°C and stirred for 2 hours After this time, the reaction mixture was cooled and concentrated under reduced pressure. The crude residue was purified by preparative HPLC to give 6-(4-amino-4methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazin-2-ol (23.00 mg, 65.11 µmol, 35% yield). .39%) as a yellow solid. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 7.71 (s, 1H), 7.58 (dd, J=7.45, 1.75 Hz, 1H), 7.40-7.27 ( m, 2H), 3.83 (br d, J=14.47 Hz, 2H), 3.41 (br d, J=8.77 Hz, 2H), 1.62 (br s, 4H), 1 .26 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ Cl ₂ N ₄ O: 353.09; the found value is 353.1.

Example 37 Synthesis of (R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazin-2-ol

(R)-6-(1-Amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazin-2-ol was synthesized by a method similar to that of Example 36 except that tert-butyl (4methylpiperidin-4-yl)carbamate was replaced by (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2sulfinamide. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.34 (s, 1H), 7.76 (s, 1H), 7.60 (br dd, J=7.61, 1.87 Hz, 1H ), 7.46-7.28 (m, 2H), 4.24-4.04 (m, 2H), 3.12-3.02 (m, 2H), 2.93 (br s, 1H) , 2.03-1.89(m, 2H), 1.85-1.39(m, 8H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₂ Cl ₂ N ₄ O: 393.12; the found value is 392.9.

Example 38 Synthesis of (R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-iodopyrazin-2-yl)-8azaspiro[4.5]decan-1-amine

Stage 1. Synthesis of 2-ethylhexyl-3-[[2-[bis(tert-butoxycarbonyl)amino]-3-chloro-4pyridyl]sulfanyl]propanoate.

To four parallel batches of 2-ethylhexyl-3-((2-amino-3-chloropyridin-4-yl)thio)propanoate (4x2.8 g, 4x8.2 mmol, 1 eq.) and Boc ₂ O (4x9.4 ml, 4x41 mmol, 5 eq.) in DCM (4x150 ml) at 25°C under an inert atmosphere, DMAP (4x201 mg, 1.6 mmol, 0.2 eq.) and Et ₃ N (4x3.4 ml, 25 mmol, 3 eq.). The resulting mixture was stirred for 12 hours after which the four batches were combined. The combined mixture was poured into water (500 ml) and extracted with DCM (3x200 ml). The combined organic extracts were washed with brine (500 ml), dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give 2-ethylhexyl-3-[[2-[bis(tert-butoxycarbonyl)amino]-3-chloro-4pyridyl]sulfanyl]propanoate (11 g, 25 mmol, yield 74.7%) as a colorless oil. 1H NMR (400

MHz, chloroform^) δ 8.27-8.26 (d, J=6.4 Hz, 1H), 7.08-7.06 (d, J=8 Hz, 1H), 4.07-4, 05 (m, 2H), 3.29-3.25 (d,

J=8 Hz, 1H), 2.77-2.73 (d, J=8 Hz, 1H), 1.56 (s, 3H), 1.40 (s, 18H), 1.40-1, 29 (m, 6H), 0.91-0.87 (m, 6H).

Stage 2. Synthesis of tert-butyl (3-chloro-4-mercaptopyridin-2-yl) carbamate.

To two parallel solutions of 2-ethylhexyl-3-[[2-[bis(tert-butoxycarbonyl)amino]-3-chloro-4pyridyl]sulfanyl]propanoate (2x5.9 g, 2x13.1 mmol, 1 eq.) in THF (2x100 ml) at -78°C in an inert atmosphere was added KOt-Bu (1 M in THF, 2x2.0 ml, 2x19.6 mmol, 1.5 eq.). The mixture was stirred at 78° C. for 10 minutes before the two batches were combined. The mixture was concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give tert-butyl-(3-chloro-4-mercaptopyridin-2-yl)carbamate (4.0 g, 15 mmol, 58.3% yield) as a yellow solid.

Step 3. Synthesis of bis-tert-butyl-(4-((3-amino-5-chloropyrazin-2-yl)thio)-3-chloropyridin-2yl)carbamate.

To a solution of bis-tert-butyl-(3-chloro-4-mercaptopyridin-2-yl)carbamate (4.00 g, 15 mmol, 1 eq.) and 3-bromo-6-chloropyrazin-2-amine (3, 20 g, 15.3 mmol, 1 eq.) in dioxane (100 ml) at 20° C. under an inert atmosphere was added DIPEA (5.36 ml, 30.6 mmol, 2 eq.). The mixture was heated to 60° C. and stirred for 2 hours. After this time, the mixture was cooled to 20° C. and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give bis-tert-butyl-(4-((3-amino-5-chloropyrazin-2-yl)thio)-3-chloropyridin-2-yl)carbamate (2.50 g, 6 .44 mmol, 41% yield as a yellow solid. 1H NMR (400 MHz, chloroform-d) δ 8.16-8.15 (d, J=5.2 Hz, 1H), 8.00 (s, 1H), 6.43-6.42 (d, J=5.2Hz, 1H), 5.23(s, 2H), 1.55(s, 9H).

Stage 4. Synthesis of tert-butyl-(3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridin-2-yl)carbamate.

To four parallel batches of bis-tert-butyl-(4-((3-amino-5-chloropyrazin-2-yl)thio)-3-chloropyridin-2-yl)carbamate (4x500 mg, 4x1.3 mmol, 1 eq.) and isopentyl nitrite (4x867 μl, 4x6.4 mmol, 5 eq.) in DME (4x5 ml) at 25°C I ₂ (4x653 mg, 4x2.6 mmol, 2 eq.) was added in one portion. The mixture was heated to 70° C. and stirred for 2 hours. After this time, the four batches were combined and poured into water (100 ml). The aqueous phase was then extracted with ethyl acetate (3x100 ml). The combined organic extracts were washed with brine (200 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give bis-tert-butyl-(3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridin-2-yl)carbamate (1.2 g, 2.4 mmol, 46.5% yield as a yellow solid.

Step 5. Synthesis of bis-tert-butyl-(4-((5-((R)-1-(((R)-tert-butylsulfinyl)amino)-8azaspiro[4.5]decan-8-yl)-3- iodopyrazin-2-yl)thio)-3-chloropyridin-2-yl)carbamate.

To two parallel batches of bis-tert-butyl-(3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridin2-yl)carbamate (2x25.0 mg, 2x62.6 µmol, 1 eq.) and (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1yl)propan-2-sulfinamide (2x16.1 mg, 2x62.6 µmol, 1 eq.) in DMF (2x2.00 ml) at 25°C in an inert atmosphere was added DIPEA (2x109 μl, 2x626 μmol, 10 eq.). The mixture was heated to 90° C. and stirred for 1 hour. After this time, the two batches were combined and poured into water (5 ml). The aqueous phase was then extracted with ethyl acetate (3x20 ml). The combined organic extracts were washed with brine (10 mL), dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to give bis-tert-butyl-(4-((5-((R)-1-(((R)- tert-butylsulfinyl)amino)-8-azaspiro[4.5]decan-8-yl)-3-iodopyrazin-2-yl)thio)-3-chloropyridin-2yl)carbamate (100 mg, crude) as a yellow oil which was applied to next step without further purification.

Step 6. Synthesis of (R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-iodopyrazin-2-yl)-8azaspiro[4.5]decan-1-amine.

To a solution of bis-tert-butyl-(4-((5-((R)-1-(((R)-tert-butylsulfinyl)amino)-8-azaspiro[4.5]decan-8yl)-3-iodopyrazin- HCl/MeOH (4 M, 520 µl , 10 equiv.). The mixture was then stirred at 20° C. for 2 hours. The mixture was then concentrated under reduced pressure and the crude residue was purified by preparative HPLC to give (R)-8-(5-((2-amino-3-chloropyridin-4-yl )thio)-6iodopyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine (14.0 mg, 27.0 µmol, 13.0% yield) as a yellow solid. 1H NMR (400 MHz, methanol-d ₄ ) : δ 8.29 (s, 1H), 7.67-7.65 (d, J=6.8 Hz, 1H), 6.31-6.30 ( d, J=6.8 Hz, 1H), 4.40-4.28 (m, 2H), 3.29-3.26 (m, 4H), 2.24-2.23 (m, 1H) , 1.90-1.59 (m, 8H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ ClIN ₆ S: 517.04; the found value is 517.1.

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Example 39 Synthesis of (R)-3-((2-amino-3-chloropyridin-4-yl)thio)-6-(1-amino-8-azaspiro[4.5]decan-8yl)pyrazine-2-carbonitrile

CI (B0Cj ₂ N o

Cui, K^CNJs]

1.10-fenantfull

Cui, K4[Ge(SL) _b ] 1,10-feiantrolpn

DMF 120°C p -S

V Me

Stage 1. Synthesis of 3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridine-2-amine.

To a solution of tert-butyl-(3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridin-2-yl)carbamate (1.10 g, 2.20 mmol, 1 eq. ) in DMF (10 ml) in an inert atmosphere were successively added CuI (83.8 mg, 440 µmol, 0.2 eq.), 1,10-phenanthroline (79.2 mg, 440 µmol, 0.2 eq.) and K4[Fe(CN) ₆ ] (1.62 g, 4.40 mmol, 2 eq.). The mixture was heated to 120° C. and stirred for 3 hours. After this time, the residue was poured into water (50 ml) and extracted with ethyl acetate (3x20 ml). The combined organic extracts were washed with brine (50 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give 3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridine-2-amine (230 mg, 576 μmol, 26% yield).

Stage 2. Synthesis of (R)-N-((R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-iodopyrazin-2-yl)-8azaspiro[4.5] decan-1-yl)-2-methylpropan-2-sulfinamide.

To two parallel batches of bis-tert-butyl-(3-chloro-4-((5-chloro-3-iodopyrazin-2-yl)thio)pyridine

2-yl)carbamate (2x25.0 mg, 2x62.6 µmol, 1 eq.) and (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1yl)propan-2- sulfinamide (2x16.1 mg, 2x62.6 μmol, 1 eq.) in DMF (2x2.00 ml) DIPEA (2x109 μl, 2x626 μmol, 10 eq.) was added at 25° C. under an inert atmosphere. The mixture was heated to 90° C. and stirred for 1 hour. After this time, the two batches were combined and poured into water (5 ml). Then the aqueous phase was extracted with ethyl acetate (3x20 ml). The combined organic extracts were washed with brine (10 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give (R)-N-((R)-8-(5-((2-amino-3 -chloropyridin-4-yl)thio)-6-iodopyrazin2-yl)-8-azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide (100 mg, crude) as a yellow oil.

Step 3. Synthesis of (R)-3-((2-amino-3-chloropyridin-4-yl)thio)-6-(1-amino-8-azaspiro[4.5]decan-8yl)pyrazine-2-carbonitrile.

To a solution of (R)-N-((R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-6-iodopyrazin-2-yl)-8azaspiro[4.5]decan- 1-yl)-2-methylpropan-2-sulfinamide (100 mg, 161 µmol, 1 eq.) in DMF (1 ml) CuI (6.13 mg, 32.2 µmol, 0.2 eq.) .), 1,10-phenanthroline (5.80 mg, 32.2 µmol, 0.2 eq.) and K4[Fe(CN) ₆ ] (118 mg, 322 µmol, 2 eq.). The resulting mixture was heated to 120° C. and stirred for 3 hours. At the end of this time, the residue was poured into water (5 ml) and extracted with ethyl acetate (3x2 ml). The combined organic extracts were washed with brine (5 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The residue was purified by preparative HPLC to give (R)-3((2-amino-3-chloropyridin-4-yl)thio)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)pyrazine -2-carbonitrile (4.00 mg, 9.62 µmol, 5.97% yield). 1 H NMR (400 MHz, methanol-d ₄ ): δ 8.52 (s, 1H), 7.64 (m, 1H), 6.00-6.01 (m, 1H), 4.30-4, 41 (m, 3H), 3.19-3.23 (m, 2H), 2.18 (m, 1H), 1.58-1.90 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₂ ClN ₇ S: 416.13; the found value is 416.1.

Example 40 Synthesis of 1-(5-(2,3-dichlorophenyl)-6-(trifluoromethyl)pyrazin-2-yl)-4-methylpiperidin-4amine

Synthesis of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-iodopyrazin-2-yl)-4-methylpiperidin-4Step 1. yl)carbamate.

To a solution of 5-chloro-2-(2,3-dichlorophenyl)-3-iodopyrazine (500 mg, 1.3 mmol, 1 eq.) in dioxane (3 ml) -yl)carbamate (418 mg, 2 mmol, 1.5 eq.) and DIEA (5 ml, 29 mmol, 22 eq.). The mixture was then heated to 90°C and stirred for 2 h. After this time, the reaction mixture was concentrated under reduced pressure and the resulting

- 128 041617 the crude residue was purified by silica gel chromatography to give tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-iodopyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate (500 mg, 888 µmol, 68% yield as a yellow solid. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.07 (s, 1H),

7.53-7.51 (m, 1H), 7.30-7.28 (m, 2H), 3.92-3.89 (m, 2H), 3.41-3.36 (m, 2H ), 2.17-2.14 (m, 2H), 1.70-1.62 (m,

2H), 1.45 (s, 9H), 1.41 (s, 3H).

Stage 2. Synthesis of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-(trifluoromethyl)pyrazin-2-yl)-4methylpiperidin-4-yl)carbamate.

To a solution of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-iodopyrazin-2-yl)-4-methylpiperidin-4yl)carbamate (350 mg, 621 µmol, 1 eq.) in DMF ( 4 ml) at 20°C were added methyl 2-chloro-2,2difluoroacetate (898 mg, 6.2 mmol, 10 eq.), CuI (118 mg, 621 μmol, 1 eq.) and KF (36 mg, 621 µmol, 1 eq.). The resulting mixture was heated to 100° C. and stirred for 10 hours. The mixture was then purified by preparative HPLC to give t-butyl-(1-(5-(2,3-dichlorophenyl)-6(trifluoromethyl)pyrazine-2 -yl)-4-methylpiperidin-4-yl)carbamate (10 mg, 18 µmol, 2.9% yield) as a white solid.

Stage 3. Synthesis of 1-(5-(2,3-dichlorophenyl)-6-(trifluoromethyl)pyrazin-2-yl)-4-methylpiperidin-4amine. A solution of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-(trifluoromethyl)pyrazin-2-yl)-4-methylpiperidin4-yl)carbamate (10 mg, 20 µmol, 1 eq.) in HCl/MeOH (4 M, 2 ml) was stirred at 20°C for 1 h, after which the mixture was concentrated under reduced pressure. The residue was purified by preparative HPLC to give 1-(5-(2,3-dichlorophenyl)-6-(trifluoromethyl)pyrazin-2-yl)-4-methylpiperidine4-amine (7.8 mg, 17.3 µmol, yield 87%) as a yellow solid. 1-(5-(2,3-Dichlorophenyl)-6(trifluoromethyl)pyrazin-2-yl)-4-methylpiperidin-4-amine was isolated as its formate salt. ¹ H NMR (400 MHz, methanol^) δ 8.54 (s, 1H), 7.64-7.62 (m, 1H), 7.39-7.36 (m, 1H), 7.28- 7.26 (m, 1H), 4.26-4.22 (m, 2H), 3.58-3.51 (m, 2H), 2.02-1.90 (m, 4H), 1, 50(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₁₇ Cl ₂ F ₃ N ₄ : 405.08; the found value is 405.0.

Example 41 Synthesis of (R)-(6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazin-2yl)methanol

Step 1. Synthesis of (R)-N-((R)-8-(5-(2,3-dichlorophenyl)-6-iodopyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)-2- methylpropane-2-sulfinamide.

5-Chloro-2-(2,3-dichlorophenyl)-3-iodopyrazine mixture (1.5 g, 3.8 mmol, 1 eq.), (R)-2-methyl-N-((R)-8azaspiro [4.5]decan-1-yl)propan-2-sulfinamide (1.3 g, 5 mmol, 1.3 eq.) in DIPEA (3 ml) and dioxane (3 ml) was heated to 110°C and stirred for 4 hours At the end of this time, the mixture was concentrated under reduced pressure, and the resulting crude residue was purified by silica gel chromatography to give (R)-N-((R)-8-(5-(2,3-dichlorophenyl)- 6-iodopyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)-2-methylpropan-2-sulfinamide (1.8 g, crude) as a yellow oil.

Step 2. Synthesis of methyl 6-((R)-1-(((R)-tert-butylsulfinyl)amino)-8-azaspiro[4.5]decan-8-yl)-3(2,3-dichlorophenyl)pyrazine -2-carboxylate.

To a solution of (R)-N-((R)-8-(5-(2,3-dichlorophenyl)-6-iodopyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2methylpropan- Pd(dppf)Cl ₂ (102.4 mg, 139.9 µmol , 0.1 eq.) and Et ₃ N (582 μl, 4.2 mmol, 3 eq.). The resulting mixture was placed under a carbon monoxide atmosphere (35 psi), heated to 45° C. and stirred for 4 hours. After this time, the reaction mixture was concentrated under reduced pressure. The crude residue thus obtained was purified by silica gel chromatography to give methyl 3-(2,3-dichlorophenyl)-6-((R)-1-((R)-1,1dimethylethylsulfinamido)-8-azaspiro[4.5] decan-8-yl)pyrazine-2-carboxylate (600 mg, crude) as a brown solid.

Stage 3. Synthesis of methyl-(R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2carboxylate.

A mixture of methyl 3-(2,3-dichlorophenyl)-6-((R)-1-((R)-1,1-dimethylethylsulfinamido)-8azaspiro[4.5]decan-8-yl)pyrazine-2-carboxylate ( 40 mg, 74 µmol, 1 eq) in HCl/MeOH (4 M, 2 mL) was stirred at 20° C. for 2 h. At the end of this time, the mixture was concentrated under reduced pressure and the resulting crude residue purified by preparative

HPLC to give methyl-(R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2carboxylate (5.8 mg, 12 µmol, yield 16%) as a yellow solid. 1H NMR (400 MHz, methanol-d4) δ 8.41 (s, 1H), 7.58-7.56 (m, 1H), 7.38-7.36 (m, 1H), 7.34- 7.30 (m, 1H), 4.48-4.35 (m, 2H), 3.73-3.67 (m, 1H), 3.65 (s, 3H), 3.24-3, 21 (m, 2H), 2.26-2.21 (m, 1H), 1.93-1.57 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₄ Cl ₂ N ₄ O ₂ : 435.13; found value: 435.

Step 4 Synthesis of (R)-(6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazin-2yl)methanol.

To a solution of methyl-(R)-6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2carboxylate (80 mg, 184 µmol, 1 eq. ) in THF (2 ml) at 0°C was added LAH (20.9 mg, 551.2 μmol, 3 eq.). The resulting mixture was stirred at 0° C. for 2 h before the reaction mixture was quenched with water (2 ml) and extracted with EtOAc (3x5 ml). The combined organic extracts were washed with brine (5 ml), dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue thus obtained was purified by preparative HPLC to give (R)-(6-(1-amino-8-azaspiro[4.5]decan-8-yl)-3-(2,3dichlorophenyl)pyrazin-2-yl) methanol (10 mg, 22 µmol, 12% yield) as a yellow solid. ¹ H NMR (400 MHz, CD3OD) δ ppm 8.16 (s, 1H), 7.64-7.60 (m, 1H), 7.38 (d, J=7.94 Hz, 1H), 7 .31 (m, J=7.94 Hz, 1H), 4.63-4.54 (m, 2H), 4.45 (m, 1H), 4.34 (m, 2H), 3.27- 3.18 (m, 2H), 2.23 (m, J=5.51 Hz, 1H), 1.92-1.53 (m, 10 H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₄ Cl ₂ N ₄ O ₂ : 407.13; found value: 407.2.

Example 42 Synthesis of (R)-8-(5-(2,3-dichlorophenyl)-6-vinylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine

(R)-8-(5-(2,3-Dichlorophenyl)-6-vinylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to that of Example 14, except that that 5-chloro-2-((2,3dichlorophenyl)thio)-3-iodopyrazine was replaced by methyl-6-((R)-1-(((R)-tert-butylsulfinyl)amino)-8azaspiro[4.5 ]decan-8-yl)-3-(2,3-dichlorophenyl)pyrazine-2-carboxylate. 1H NMR (400 MHz, methanol ₄ ) δ 8.51 (s, 1H), 8.16 (s, 1H), 7.64-7.61 (m, 1H), 7.42-7.38 (m , 1H), 7.36-7.27 (m, 1H), 6.41-6.28 (m, 2H), 5.425.39 (m, 1H), 4.58-4.39 (m, 2H ), 3.25-3.20 (m, 2H), 2.25-2.22 (m, 1H), 1.92-1.44 (m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₄ Cl ₂ N ₄ : 403.14; found value: 403.1.

Example 43 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichloropyridin-4-yl)thio)-5methylpyrazin-2- yl) methanol.

Me

ABOUT

Cl Me Cl Me

Stage 1. Synthesis of 2-ethylhexyl-3-((2,3-dichloropyridin-4-yl)thio)propanoate.

To a solution of 2,3-dichloro-4-iodopyridine (50 g, 183 mmol, 1 eq.) in dioxane (500 ml) was added 2-ethylhexyl-3-sulfanylpropanoate (52 g, 237 mmol, 1.3 eq.), Xantphos ( 11 g, 18 mmol, 0.1 eq.), DIPEA (71 g, 547 mmol, 96 ml, 3 eq.) and Pd ₂ (dba) ₃ (8.4 g, 9.1 mmol, 0.05 eq. .). The reaction mixture was then heated to 110° C. and stirred for 2 hours. After this time, the reaction mixture was filtered and concentrated under reduced pressure. The crude residue thus obtained was purified by silica gel chromatography to give 2-ethylhexyl-3-((2,3-dichloropyridin-4yl)thio)propanoate (42 g, 11 mmol, 63% yield) as a brown oil. ¹ H NMR (400 MHz, chloroform-d) δ 8.15 (d, J=5.26 Hz, 1H), 7.02 (d, J=5.26 Hz, 1H), 4.05 (d , J=5.70 Hz, 2H), 3.25 (t, J=7.45 Hz, 2H), 2.75 (t, J=7.45 Hz, 2H), 1.62-1.53 (m, 1H), 1.42-1.26 (m, 8H), 0.88 (t, J=7.45 Hz, 6H).

Stage 2. Synthesis of 2,3-dichloropyridine-4-thiol.

To a solution of 2-ethylhexyl-3-((2,3-dichloropyridin-4-yl)thio)propanoate (6.0 g, 16 mmol, 1.0 eq.) in

- 130 041617

THF (60 ml) at -78°C in an inert atmosphere was added KOt-Bu (1 M in THF, 32 ml, 32 mmol, 2 eq.). The reaction mixture was stirred at -78°C for 1 h. The reaction mixture was then allowed to warm to 25°C and ethyl acetate (20 ml) and 5% K2CO3 (40 ml) were added. The resulting aqueous layer was then extracted with ethyl acetate (10 ml). The aqueous phase was then adjusted to pH 3 with aqueous HCl (2 M), extracted with ethyl acetate (2x40 ml). The combined organic extracts were washed with brine (40 ml), dried over Na ₂ SO ₄ and filtered. To this filtrate was added dioxane (100 ml) and the resulting solution was concentrated under reduced pressure to give a solution of 2,3-dichloropyridine-4-thiol (1.3 g, crude) in dioxane (40 ml) which was used in subsequent reactions without additional cleaning.

Stage 3. Synthesis of 5-chloro-2-((2,3-dichloropyridin-4-yl)thio)-3-methylpyrazine.

To a solution of 2-bromo-5-chloro-3-methylpyrazine (1.0 g, 4.8 mmol, 1 eq.) in dioxane (10 ml) was added DIPEA (1.7 ml, 9.6 mmol, 2 eq. ), 2,3-dichloropyridine-4-thiol (1.3 g, 7.2 mmol, 1.5 eq.), Xantphos (279 mg, 482 µmol, 0.1 eq.), Pd ₂ (dba) ₃ (353 mg, 385 µmol, 0.08 eq). The reaction mixture was heated to 90° C. and stirred for 1 hour. After this time, the reaction mixture was filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give 5-chloro-2-((2,3-dichloropyridin-4-yl)thio)-3-methylpyrazine (730 mg, 2.5 mmol, 53% yield) as white solid.

Stage 4. Synthesis of tert-butyl-(R)-(8-(5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro [4.5] decan-1 - yl) carbamate.

(R)- 2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide (738 mg, 2.8 mmol, 1.2 eq) and NMP (3 ml). Then the reaction mixture was heated to 130°C under the influence of microwave radiation and stirred for 2 h. After this time, the reaction mixture was cooled to 25°C and Boc ₂ O (1.3 ml, 5.6 mmol, 2 eq.) was added to the reaction mixture. The resulting mixture was stirred at 25° C. for 16 hours. After this time, the reaction mixture was filtered and concentrated under reduced pressure. The crude residue thus obtained was purified by silica gel chromatography to give t-butyl-(R)-(8-(5((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)- 8-azaspiro[4.5]decan-1-yl)carbamate (535 mg, 1.0 mmol, 36% yield) as a white solid.

Step 5. Synthesis of (R)-tert-butyl-(8-(3-bromo-5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2yl)-8-azaspiro[4.5] decan-1-yl)carbamate.

To a solution of (R)-tert-butyl-(8-(5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl) carbamate (535 mg, 1.0 mmol, 1 eq.) in DCM (5 ml) was added NBS (363 mg, 2.0 mmol, 2 eq.). Then the reaction mixture was stirred at 25°C for 5 min before the reaction mixture was concentrated under reduced pressure. The crude residue thus obtained was purified by silica gel chromatography to give (R)-tert-butyl-(8-(3-bromo-5((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2 -yl)-8-azaspiro[4.5]decan-1-yl)carbamate (360 mg, 596 µmol, 58% yield) as a white solid.

Step 6. Synthesis of (R)-methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-((2,3dichloropyridin-4-yl)thio )-5-methylpyrazine-2-carboxylate.

To a solution of (R)-tert-butyl-(8-(3-bromo-5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan- 1-yl)carbamate (360 mg, 596 μmol, 1 eq.) in MeOH (10 ml) was added Et ₃ N (165 μl, 1.2 mmol, 2 eq.) and Pd(dppf)Cl ₂ (44 mg, 60 µmol, 0.1 eq.). Then the reaction mixture was heated to 50°C and stirred for 16 h in an atmosphere of CO (50 psi). After this time, the reaction mixture was filtered and concentrated under reduced pressure. The crude residue was then purified by silica gel chromatography to give (R)-methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-((2,3- dichloropyridin-4-yl)thio)-5-methylpyrazine2-carboxylate (200 mg, 343 µmol, 58% yield) as a white solid.

Step 7. Synthesis of (R)-methyl-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichloropyridin-4yl)thio)-5-methylpyrazin-2 -carboxylate.

A mixture of (R)-methyl-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-((2,3dichloropyridin-4-yl)thio)-5 -methylpyrazine-2-carboxylate (100 mg, 171 μmol, 1 eq.) in HCl/EtOAc (4 M, 1 ml) was stirred at 25°C for 1 h. After this time, the reaction mixture was filtered and concentrated under reduced pressure . The mixture was then diluted with MeOH (3 ml) and adjusted to pH 7 with saturated aqueous NaHCO ₃ . The aqueous solution was then extracted with ethyl acetate (3x3 ml) and the combined organic extracts were washed with brine, dried over Na ₂ SO ₄ , filtered and concentrated to give (R)-methyl-3-(1-amino-8azaspiro[4.5]decane-8- yl)-6-((2,3-dichloropyridin-4-yl)thio)-5-methylpyrazine-2-carboxylate (120 mg, 249 µmol, 72% yield) as a yellow solid, which was used in the next step without additional cleaning. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₅ Cl ₂ N ₅ O ₂ S: 4 82.11; found value 4 82.1.

- 131 041617

Step 8. Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichloropyridin-4-yl)thio)-5methylpyrazin-2- yl) methanol.

To a solution of (R)-methyl-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichloropyridin-4-yl)thio)-5methylpyrazin-2-carboxylate (60 mg, 124 µmol, 1 eq.) in THF (1.0 ml) at 0°C in an inert atmosphere was added LAH (14 mg, 373 µmol, 3 eq.). The reaction mixture was then heated to 25° C. and stirred for 1 hour. After this time, the reaction mixture was quenched by adding MeOH (5 ml), filtered and concentrated under reduced pressure. The crude residue was purified by preparative HPLC to give (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3dichloropyridin-4-yl)thio)-5 -methylpyrazin-2-yl)methanol (13 mg, 28 µmol, 11% yield) as a white solid. 1H NMR (400 MHz, methanol-d ₄ ) δ 8.67-8.42 (m, 1H), 7.99 (d, J=5.26 Hz, 1H), 6.65 (d, J=5 .26 Hz, 1H), 6.65 (d, . LC-MS (ESI): mass/charge: [M+H] calcd for C ₂₀ H ₂₅ Cl ₂ N ₅ OS: 454.12; found value 454 ,1.

Example 44 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl)methanol

CL Me

ChnCho (R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5-methylpyrazin-2yl)methanol was synthesized by the method similar to the method in example 43, except that 2,3-dichloropyridine-4-thiol was replaced by 2,3-dichlorobenzenethiol. ¹ H NMR (400 MHz, methanol-d ₄ ) δ 8.54 (s, 1H), 7.42 (dd, J=8.00, 1.40 Hz, 1H), 7.18 (t, J= 8.06 Hz, 1H), 6.94 (dd, J=7.94, 1.46 Hz, 1H), 4.59 (s, 2H), 3.87-3.72 (m, 2H), 3.25 (t, J=6.84 Hz, 1H), 3.20-3.07 (m, 2H), 2.50 (s, 3H), 2.30-2.17 (m, 1H) , 1.96-1.68 (m, 8H), 1.56 (br t, J=11.79 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C21H26Cl2N4OS: 453.12; found value: 453.1.

Example 45 Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-((2,3-dichlorophenyl)thio)-5-methylpyrazin2-yl)methanol

CL Me

(3-(4-Amino-4-methylpiperidin-1-yl)-6-((2,3-dichlorophenyl)thio)-5-methylpyrazin-2-yl)methanol was synthesized by a method similar to the method in example 43, for except that 2,3dichloropyridin-4-thiol and (R)-2-methyl-N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide were replaced by 2,3 -dichlorobenzenethiol and tert-butyl-(4-methylpiperidin-4-yl)carbamate, respectively. ¹ H NMR (400 MHz, methanol-d4) δ 8.54 (s, 1H), 7.44 (dd, J=8.06, 1.34 Hz, 1H), 7.19 (t, J=8 .00 Hz, 1H), 6.98 (dd, J=7.94, 1.34 Hz, 1H), 4.59 (s, 2H), 3.76 (dt, J=13.93, 4, 15 Hz, 2H), 2.51 (s, 3H), 2.02-1.94 (m, 2H), 1.93-1.84 (m, 2H), 1.49 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ OS: 413.09; found value: 413.1.

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Example 46 Synthesis of (6-((2-amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4-methylpiperidin-1-yl)-5methylpyrazin-2-yl)methanol

Stage 1. Synthesis of ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate.

Diethyl 2-oxopropanedioate (221.2 ml, 1.4 mol, 1 eq.) was added dropwise to a suspension of propane-1,2diamine (122.6 ml, 1.4 mol, 1 eq.) in EtOH (1 L ) at 0°C and the mixture was stirred at room temperature for 1.5 hours. The resulting milky white suspension was heated to 85°C and stirred for 20 hours. After this time, the reaction mixture was concentrated and purified by chromatography on silica gel to give ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate (47 g, 257.9 mmol, 17.9% yield) as a yellow solid.

Stage 2. Synthesis of ethyl 3-chloro-5-methylpyrazine-2-carboxylate.

A mixture of ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate (5.00 g, 27.45 mmol, 1 eq.) in POCl ₃ (50 ml) was heated to 110° C. and stirred for 3 h. this time the reaction mixture was concentrated under reduced pressure and extinguished by adding saturated aqueous NaHCO ₃ (150 ml). The aqueous mixture was extracted with ethyl acetate (3x80 ml) and the combined organic extracts were concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give ethyl 3-chloro-5-methylpyrazine-2-carboxylate (1.10 g, 5.48 mmol, 19.96% yield) as a pale yellow oil. ¹ H NMR (400 MHz, chloroform-d) δ 8.33 (s, 1H), 4.47 (m, 2H), 2.59 (s, 3H), 1.41 (t, J=7.2 Hz, 3H).

Step 3. Synthesis of ethyl 3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-5methylpyrazin-2-carboxylate.

To a solution of ethyl 3-chloro-5-methylpyrazin-2-carboxylate (3.00 g, 14 mmol, 1 eq.) in dioxane (30 ml) was added tert-butyl-(4-methylpiperidin-4-yl)carbamate ( 4.81 g, 22.4 mmol, 1.5 eq.) and DIPEA (13 ml, 74.7 mmol, 5 eq.). The reaction mixture was then heated to 80° C. and stirred for 16 hours. At the end of this time, the reaction mixture was poured into water (150 ml) and the resulting aqueous mixture was extracted with ethyl acetate (3x50 ml). The combined organic extracts were washed with brine (100 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to give ethyl 3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-5-methylpyrazin-2carboxylate (4.50 g, 11.8 mmol , 79% yield) as a yellow solid.

Step 4. Synthesis of ethyl 6-bromo-3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-5methylpyrazin-2-carboxylate.

To four parallel batches of ethyl 3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1yl)-5-methylpyrazin-2-carboxylate (4x1.05 g, 4x2.77 mmol, 1 eq) in DCM (4x10 ml) was added with NBS (4x739 mg, 4x4.16 mmol, 1.5 eq.) and the resulting reaction mixtures were stirred at 25°C for 1 hour. Four batches were combined and the resulting mixture was quenched by adding saturated aqueous solution of Na2SO3 (50 ml) at 25°C. Then the aqueous phase was extracted with DCM (3x50 ml). The combined organic extracts were washed with brine (100 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure to give 6-bromo-3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidine-1 -yl)-5-methylpyrazine-2-carboxylate (3.80 g, 8.31 mmol, 75% yield), which was used in the next step without further purification.

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Step 5. Synthesis of ethyl 6-((2-(bis(tert-butoxycarbonyl)amino)-3-chloropyridin-4-yl)thio)-3-(4((tert-butoxycarbonyl)amino)-4-methylpiperidine- 1-yl)-5-methylpyrazine-2-carboxylate.

Ethyl-6-((2-(bis(tert-butoxycarbonyl)amino)-3-chloropyridin-4-yl)thio)-3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)- 5-methylpyrazin-2-carboxylate was synthesized by a method similar to that for 3-chloro-4-((5-chloro-3-methylpyrazin-2-yl)thio)pyridine-2amine. 1H NMR (400 MHz, CDCl ₃ ) δ 8.04-8.02 (m, 1H), 6.51-6.50 (m, 1H), 4.38-4.34 (m, 2H), 3 .70-3.65 (m, 2H), 3.38-3.32 (m, 2H), 2.36 (s, 3H), 2.10-2.04 (m, 2H), l.65 -1.59(m, 2H), 1.37-1.33(m, 34H).

Step 6. Synthesis of ethyl 6-((2-amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4-methylpiperidin-1-yl)-5methylpyrazin-2-carboxylate.

6-((2-Amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4-methylpiperidin-1-yl)-5-methylpyrazin-2carboxylate was synthesized by a method similar to that for (R) -8-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine. LC-MS (ESI): mass/charge: [M+H] calc. For C ₁₉ H ₂₆ ClN ₆ O ₂ S: 437.14; the found value is 437.1.

Step 7 Synthesis of (6-((2-amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4-methylpiperidin-1-yl)-5methylpyrazin-2-yl)methanol.

To a mixture of ethyl 6-((2-amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4-methylpiperidin-1-yl)-5methylpyrazin-2-carboxylate (1.70 g, 3.89 mmol, 1 eq.) in THF (20 ml) at 0° C. under an inert atmosphere, LAH (369 mg, 9.73 mmol, 2.5 eq.) was added in portions. The mixture was then heated to 35° C. and stirred for 12 hours. After this time, the reaction mixture was quenched by adding water (1 ml) and stirred for 10 minutes. Then the aqueous phase was extracted with ethyl acetate (3x50 ml) and the combined organic extracts were washed with saline (50 ml), dried over anhydrous Na ₂ SO ₄ , filtered and concentrated under reduced pressure. The crude residue was purified by preparative HPLC to give (6-((2-amino-3-chloropyridin-4-yl)thio)-3-(4-amino-4methylpiperidin-1-yl)-5-methylpyrazin-2-yl ) methanol (200 mg, 506 µmol, 13% yield). 1H NMR (400 MHz, methanol-d ₄ ) δ 8.51 (s, 1H), 7.58-7.57 (m, 1H), 5.89-5.87 (m, 1H), 4.62 (s, 2H), 3.86-3.83 (m, 2H), 3.393.29 (m, 2H), 2.48 (s, 3H), 1.95-1.86 (m, 4H), 1.48(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₃ ClN ₆ OS: 395.13; the found value is 395.3.

Example 47 Synthesis of 1-(5-(2-chlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

-(5-(2-Chlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 23, except that (2,3-dichlorophenyl)boronic acid was replaced by (2-chlorophenyl)boronic acid. 1-(5-(2-Chlorophenyl)-6-methylpyrazin-2-yl)-4methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.32 (s, 1H, HCOOH), 8.22 (d, J=0.8 Hz, 1H), 7.58-7.55 (m, 1H) , 7.46-7.42 (m, 2H), 7.39-7.35 (m, 1H), 3.99 (dt, J=13.8, 5.2 Hz, 2H), 3.44 (ddd, J=13.2, 8.6, 4.1Hz, 2H), 2.15 (s, 3H), 1.72 (dt, J=11.0, 5.1Hz, 4H), 1.34(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₁ ClN ₄ : 317.15; the found value is 317.53.

Example 48 Synthesis of 1-(5-(2-fluorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

-(5-(2-Fluorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 24, except that (2,3-dichlorophenyl)boronic acid was replaced by (2-fluorophenyl)boronic acid. 1-(5-(2-Fluorophenyl)-6-methylpyrazin-2-yl)-4methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.32 (s, 1H, HCOOH), 8.22 (d, J=0.8 Hz, 1H), 7.58-7.55 (m, 1H ), 7.46-7.42 (m, 2H), 7.39-7.35 (m, 1H), 3.99 (dt, J=13.8, 5.2 Hz, 2H), 3, 44 (ddd, J=13.2, 8.6, 4.1 Hz, 2H), 2.15 (s, 3H), 1.72 (dt, J=11.0, 5.1 Hz, 4H) , 1.34 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₁ FN ₄ : 301.18; the found value is 301.47.

Example 49 Synthesis of 1-(5-(2,3-difluorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

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1-(5-(2,3-Difluorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine.

1-(5-(2,3-Difluorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 23, except that (2,3-dichlorophenyl )boronic acid was replaced by (2,3-difluorophenyl)boronic acid. 1-(5-(2,3-Difluorophenyl)-6methylpyrazin-2-yl)-4-methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₅ ) δ 8.28 (s, 1H), 7.49 (dtd, J=10.0, 7.9, 1.8 Hz, 1H), 7.35-7 .2 (m, 2H), 4.04-3.93 (m, 2H), 3.48 (dt, J=13.2, 6.3 Hz, 2H), 2.25 (d, J=1 .7 Hz, 3H), 1.68 (t, J=5.8 Hz, 4H), 1.32 (s, 3H). LCMS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ F ₂ N ₄ : 319.17; the found value is 319.46.

Example 50 Synthesis of 1-(5-(4-chlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

^0Ι γΛ Me

I Lnh ₂

Me

-(5-(4-Chlorophenyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 24, except that (2,3-dichlorophenyl)boronic acid was replaced by (4-chlorophenyl)boronic acid. 1-(5-(4-Chlorophenyl)-6-methylpyrazin-2-yl)-4methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d6) δ 8.24 (s, 1H, HCOOH), 7.58 (d, J=8.5 Hz, 2H), 7.49 (d, J=8.5 Hz, 2H), 3.86(s, 2H), 3.58-3.48(m, 3H), 2.42(s, 3H), 1.61(s, 4H), 1.25(s , 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₁ ClN ₄ : 317.15; the found value is 317.46.

Example 51 Synthesis of 1-(5-(5,6-dichloropyridin-3-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

1-(5-(5,6-Dichloropyridin-3-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 24, except that (2 ,3dichlorophenyl)boronic acid was replaced by (5,6-dichloropyridin-3-yl)boronic acid. 1-(5(5,6-Dichloropyridin-3-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.59 (d, J=2.2 Hz, 1H), 8.30-8.28 (m, 2H), 3.93-3.83 ( m, H), 3.58 (t, J=7.4 Hz, 2H), 2.46 (d, J=0.5 Hz, 3H), 1.62 (d, J=5.6 Hz, 4H), 1.26 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for Ci ₆ Hi ₉ Cl ₂ N ₅ : 352.10; the found value is 352.39.

Example 52 Synthesis of 1-(5-(1-(4-chlorophenyl)vinyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

1-(5-(1-(4-Chlorophenyl)vinyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 24, except that (2, 3-dichlorophenyl)boronic acid has been replaced by (1-(4-chlorophenyl)vinyl)boronic acid. 1-(5-(1(4-Chlorophenyl)vinyl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.42 (s, 1H), 8.13 (s, 1H), 7.41-7.37 (m, 2H), 7.28-7.24 (m, 2H), 5.88 (d, J=1.0 Hz, 1H), 5.34 (d, J=1.0 Hz, 1H), 3.69 (dt, J=12.3, 5.9 Hz, 2H), 3.60 (dt, J=12.7, 5.5 Hz, 2H), 2.16 (s, 3H), 1.54 (t, J=5.8 Hz, 4H), 1.18(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₃ ClN ₄ : 343.16; the found value is 343.51.

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Example 53 Synthesis of 8-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azabicyclo[3.2.1]octan-3 amine

8-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azabicyclo[3.2.1]octane-3-amine was synthesized by a method similar to the method in example 1, except that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(8-azabicyclo[3.2.1]octan-3yl)carbamate . 8-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azabicyclo[3.2.1]octane-3-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.37 (s, 1H), 8.14 (d, J=0.7 Hz, 1H), 7.47 (dd, J=8.0, 1 .4 Hz, 1H), 7.25 (t, J=8.0 Hz, 1H), 6.79 (dd, J=8.0, 1.4 Hz, 1H), 7.25 (t, J =11.2, 5.6 Hz, 1H), 2.40 (d, J=0.5 Hz, 3H), 1.98 (dd, J=8.2, 4.2 Hz, 2H), 1 .80 (d, J=1.3 Hz, 4H), 1.58-1.50 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₀ Cl ₂ N ₄ S: 395.08; the found value is 395.4.

Example 54 Synthesis of 2-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2-azaspiro[3.3]heptan-6amine

2-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2-azaspiro[3.3]heptan-6-amine was synthesized by a method similar to that of Example 1, except that that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(2-azaspiro[3.3]heptan-6yl)carbamate. 2-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2-azaspiro[3.3]heptan-6-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.39 (s, 1H, HCOOH), 7.92 (d, J=0.7 Hz, 1H), 7.56 (t, J=5.8 Hz, 1H), 7.43 (dt, J=8.0, 1.1 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.67 (dd, J=8 .1, 1.4 Hz, 1H), 3.78 (s, 2H), 3.53 (d, J=5.8 Hz, 2H), 3.52-3.43 (m, 1H), 2 .37 (d, J=1.7 Hz, 3H), 2.26-2.19 (m, 2H), 1.84-1.75 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₁₈ Cl ₂ N ₄ S: 381.06; the found value is 381.41.

Example 55 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)azepane-4-amine

1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)azepane-4-amine was synthesized by a method similar to that of Example 1, except that 2-methyl-N- ((R)-8-azaspiro[4.5]decan-1yl)propan-2-sulfinamide was replaced by tert-butylazepane-4-ylcarbamate. 1-(5-((2,3-Dichlorophenyl)thio)6-methylpyrazin-2-yl)azepane-4-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.40 (s, 1H), 8.09 (d, J=0.7 Hz, 1H), 7.45 (dd, J=8.0, 1 .4 Hz, 1H), 7.24 (t, J=8.0 Hz, 1H), 6.70 (dd, J=8.1, 1.4 Hz, 1H), 3.91-3.83 (m, 1H), 3.66 (q, J=4.9 Hz, 2H), 3.52 (ddd, J=14.6, 9.7, 3.3 Hz, 1H), 3.07 ( td, J=9.8, 8.5, 5.1 Hz, 1H), 2.39 (d, J=0.5 Hz, 3H), 2.13-2.04 (m, 1H), 2 .00-1.81 (m, 2H), 1.77-1.58 (m, 1H), 1.49-1.39 (m, 1H) LC-MS (ESI): mass/charge: [M +H] calc. for C^C^S: 383.08; the found value is 383.33.

Example 56 Synthesis of N-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2-azaspiro[3.4]octane-6amine

N-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2-azacniro[3.4]octane-6-amine was synthesized by a method similar to that of Example 1, except that that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-6-amino-2azaspiro[3.4]octane-2-carboxylate. N-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-2azaspiro[3.4]octane-6-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.44 (s, 1H), 7.82 (d, J=0.7 Hz, 1H), 7.59 (d, J=6.7 Hz, 1H ), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.23 (t, J=8.1 Hz, 1H), 6.66 (dd, J=8.1, 1.4 Hz, 1H), 4.14 (q, J=6.8 Hz, 1H), 3.80-3.64 (m, 4H), 2.36 (d, J=0.6 Hz, 3H), 2.30 (dd, J=13.4, 7.4 Hz, 1H), 2.06-1.97 (m, 2H), 1.92-1.72 (m, 2H), 1 .55-1.46 (m, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₀ C ₁₂ N ₄ S: 395.08; the found value is 395.4.

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Example 57 Synthesis of 1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-1,4-diazepane

1-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-1,4-diazepane was synthesized by a method similar to that of Example 1, except that 2-methyl-N -((R)-8-azaspiro[4.5]decan-1yl)propane-2-sulfinamide was replaced by tert-butyl-1,4-diazepan-1-carboxylate. 1-(5-((2,3Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-1,4-diazepane was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.32 (s, 1H), 8.09 (s, 1H), 7.45 (dd, J=8.0, 1.4 Hz, 1H) , 7.2 (td, J=8.0, 1.3 Hz, 1H), 6.70 (dd, J=8.0, 1.4 Hz, 1H), 7.2 (td, J=12 .2, 5.5 Hz, 4H), 2.99 (d, J=6.5 Hz, 2H), 2.82 (d, J=5.8 Hz, 2H), 2.38 (d, J =1.2 Hz, 3H), 1.85 (d, J=1.9 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ C ₁₂ N ₄ S: 369.06; the found value is 369.34.

Example 58 Synthesis of 7-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-7-azaspiro[3.5]nonan-2amine

7-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-7-azaspiro[3.5]nonan-2-amine was synthesized by a method similar to the method in example 1, except that that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(7-azaspiro[3.5]nonan-2yl)carbamate. 7-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-7-azaspiro[3.5]nonan-2-amine was isolated as its formate salt after HPLC purification. 1 H NMR (500 MHz, DMSO-d ₆ ) δ 8.40 (s, 1H), 8.23 (s, 1H), 7.46 (dd, J=8.0, 1.4 Hz, 1H), 7.23 (t, J=8.1 Hz, 1H), 6.72 (dd, J=8.0, 1.4 Hz, 1H), 3.66-3.49 (m, 5H), 2 .37 (s, 3H), 2.21-2.11 (m, 2H), 1.75 (dd, J=11.5, 8.7 Hz, 2H), 1.59 (dt, J=14 .2, 5.6 Hz, 4H) LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₂ C1 ₂ N ₄ S: 40 9.09; the found value is 409.46.

Example 59 Synthesis of N-(2-(azetidin-3-yl)ethyl)-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-amine

N-(2-(Azetidin-3-yl)ethyl)-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-amine was synthesized by a method similar to that of Example 1, except that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-3-(2-aminoethyl)azetidine-1carboxylate. N-(2-(Azetidin-3-yl)ethyl)-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.42 (s, 1H), 7.84 (d, J=0.8 Hz, 1H), 7.56 (t, J=5.7 Hz, 1H), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.65 (dd, J=8.1 , 1.4 Hz, 1H), 3.90-3.82 (m, 2H), 3.61-3.53 (m, 2H), 3.25 (q, J=6.5 Hz, 2H) , 2.80 (p, J=1.7 Hz, 1H), 2.36 (d, J=0.6 Hz, 3H), 1.85 (q, J=7.1 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ C ₁₂ N ₄ S: 369.06; the found value is 369.34.

Example 60 Synthesis of N-((2-azaspiro[3.3]heptαn-6-yl)methyl)-5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-amine

N-((2-Azaspiro[3.3]heptan-6-yl)methyl)-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-amine was synthesized by a method similar to the method in example 1, for except that 2-methyl-N-((R)8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-6-(aminomethyl)-2azaspiro[3.3]heptan- 2-carboxylate. N-((2-Azaspiro[3.3]heptan-6-yl)methyl)-5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 10.71 (s, 1H), 10.13 (d, J=0.7 Hz, 1H), 9.83 (t, J=5.6 Hz, 1H ), 9.72 (dd, J=8.0, 1.4 Hz, 1H), 9.51 (t, J=8.0 Hz, 1H), 8.93 (dd, J=8.1, 1.4 Hz, 1H), 6.05 (d, J=29.9 Hz, 4H), 5.59-5.54 (m, 2H), 4.64 (d, J=0.6 Hz, 3H), 4.58-4.52 (m, 2H), 4.20 (dd, J=12.3, 7.2 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C^CW 395.08; the found value is 395.4.

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Example 61 Synthesis of 5-((2,3-dichlorophenyl)thio)-6-methyl-N-(pyrrolidin-3-ylmethyl)pyrazin-2-amine

5-((2,3-Dichlorophenyl)thio)-6-methyl-N-(pyrrolidin-3-ylmethyl)pyrazin-2-amine was synthesized by a method similar to the method in example 1, except that 2-methyl- N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-3-(aminomethyl)pyrrolidine1-carboxylate. 5-((2,3-Dichlorophenyl)thio)-6-methyl-N-(pyrrolidin-3-ylmethyl)pyrazin-2-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.41 (s, 1H), 7.88 (d, J=0.7 Hz, 1H), 7.71 (t, J=5.6 Hz, 1H), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.66 (dd, J=8.1 , 1.4 Hz, 1H), 3.40-3.27 (m, 2H), 3.23-3.09 (m, 2H), 3.02 (q, J=9.3, 8.7 Hz, 1H), 2.81 (dd, J=11.3, 7.0 Hz, 1H), 2.36 (d, J=0.6 Hz, 3H), 1.99 (td, J=12 .9, 7.4 Hz, 1H), 1.65-1.54 (m, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ Cl ₂ N ₄ S: 369.06; the found value is 369.34.

Example 62 Synthesis of N ¹ -(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)butan-1,4-diamine

hh ₂

N ¹ -(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)butan-1,4-diamine was synthesized by a method similar to the method in example 1, except that 2-methyl -N-((R)-8-azaspiro[4.5]decan1-yl)propan-2-sulfinamide was replaced by tert-butyl-(4-aminobutyl)carbamate. N1-(5-((2,3Dichlorophenyl)thio)-6-methylpyrazin-2-yl)butan-1,4-diamine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.45 (s, 1H), 7.86 (d, J=0.8 Hz, 1H), 7.64 (t, J=5.5 Hz, 1H ), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.1 Hz, 1H), 6.64 (dd, J=8.1, 1.4 Hz, 1H), 3.35-3.26 (m, 2H), 2.75 (t, J=6.7 Hz, 2H), 2.36 (d, J=0.6 Hz, 3H), 1.58 (p, J=4.1, 3.4 Hz, 4H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₅ H ₁₈ Cl ₂ N ₄ S: 357.06; the found value is 357.43.

Example 63 Synthesis of 5-((2,3-dichlorophenyl)thio)-6-methyl-N-(piperidin-4-ylmethyl)pyrazin-2-amine

CI Ck

5-((2,3-Dichlorophenyl)thio)-6-methyl-N-(piperidin-4-ylmethyl)pyrazin-2-amine was synthesized by a method similar to the method in example 1, except that 2-methyl- N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-4-(aminomethyl)piperidine-1carboxylate. 5-((2,3-Dichlorophenyl)thio)-6-methyl-N-(piperidin-4-ylmethyl)pyrazin-2-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.41 (s, 1H), 7.87 (d, J=0.7 Hz, 1H), 7.59 (t, J=5.7 Hz, 1H), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.65 (dd, J=8.1 , 1.4 Hz, 1H), 3.20 (t, J=6.0 Hz, 2H), 3.10 (d, J=12.4 Hz, 2H), 2.68-2.59 (m , 2H), 2.35 (d, J=0.6Hz, 3H), 1.75 (d, J=12.9Hz, 3H), 1.22 (q, J=12.7Hz, 2H ). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ Cl ₂ N ₄ S: 383.08; the found value is 383.41.

Example 64 Synthesis of N ¹ -(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)propan-1,3-diamine

Cl ck A ,s νη ₂

N ¹ -(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)propan-1,3-diamine was synthesized by a method similar to the method in example 1, except that 2-methyl -N-((R)-8-azaspiro[4.5]decan1-yl)propan-2-sulfinamide was replaced by tert-butyl-(3-aminopropyl)carbamate. N1-(5-((2,3Dichlorophenyl)thio)-6-methylpyrazin-2-yl)propan-1,3-diamine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.42 (s, 1H), 7.86 (d, J=0.7 Hz, 1H), 7.70 (t, J=5.6 Hz, 1H), 7.44 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.65 (dd, J=8.1 , 1.4 Hz, 1H), 3.36 (q, J=6.5 Hz, 2H), 2.81 (dd, J=8.2, 6.4 Hz, 2H), 2.37 (d , J=0.6 Hz, 3H), 1.80 (p, J=1.0 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₄ H ₁₆ Cl ₂ N ₄ S: 343.05; the found value is 343.37.

Example 65 Synthesis of (1R,3R,5S)-N-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-9-methyl-9azabicyclo[3.3.1]nonane-3 -amine.

CI sk A/S

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Synthesis of (1R,3R,5S)-N-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-9-methyl-9azabicyclo[3.3.1]nonan-3-amine was synthesized by a method similar to the method in example 1, except that 2-methyl-N-((R)-8-azacniro[4.5]decan-1-yl)nponan-2-sulfinamide was replaced by (1R,3R, 5S)-9-methyl-9-azabicyclo[3.3.1]nonan-3-amine. In the synthesis of (1R,3R,5S)-N-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-9-methyl-9-azabicyclo[3.3.1]nonan-3-amine isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.21 (s, 1H), 7.79 (d, J=0.7 Hz, 1H), 7.42 (dd, J=8.0, 1 .4 Hz, 1H), 7.32 (d, J=8.4 Hz, 1H), 7.22 (t, J=8.1 Hz, 1H), 6.65 (dd, J=8.1 , 1.3 Hz, 1H), 3.00 (d, J=11.2 Hz, 2H), 2.41 (s, 3H), 2.36 (d, J=0.6 Hz, 3H), 2.34-2.26 (m, 2H), 2.01-1.85 (m, 3H), 1.46 (d, J=11.3 Hz, 1H), 1.35-1.26 ( m, 2H), 0.93 (d, J=11.9 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C2oH24C12N4S: 423.11; the found value is 423.45.

Example 66 Synthesis of N-(5-((2,3-dichlorophenyl)thio)-6-methylpirazin-2-yl)-3-azabicyclo[3.2.1]octan-8amine

N-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-3-azabicyclo[3.2.1]octane-8-amine was synthesized by a method similar to that of Example 1, except that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-8-amino-3azabicyclo[3.2.1]octane-3- carboxylate. N-(5-((2,3-Dichlorophenyl)thio)-6-methylnirazin-2-yl)-3azabicyclo[3.2.1]octane-8-amine was isolated as its formate salt after HPLC purification. 1H NMR (500

MHz, DMSO-d6) δ 8.36 (s, 1H), 8.06 (s, 1H), 7.72 (d, J=6.0 Hz, 1H), 7.44 (dd, J=8 .0, 1.4 Hz, 1H), 7.24 (d, J=8.0 Hz, 1H), 6.68 (dd, J=8.1, 1.4 Hz, 1H), 3.92 -3.85 (m, 1H), 3.13 (d, J=12.7 Hz, 2H), 2.56 (d, J=14.3 Hz, 2H), 2.36 (s, 3H) , 2.18 (s, 2H), 1.85-1.71 (m, 4H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₀ Cl ₂ N ₄ S: 395.08; the found value is 395.4.

Example 67 Synthesis of azabicyclo[3.1.0]hexane-6-amine

(1R,5S,6S)-3-(5-((2,3-dichlorophenyl)thio)-6-methylnirazin-2-yl)-3-

(1R,5S,6S)-3-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-3-azabicyclo[3.1.0]hexane-6-amine was synthesized by the method similar to the method in example 1, except that 2-methylN-((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by exo-6-(boc-amino)- 3azabicyclo[3.1.0]hexane. (1R,5S,6S)-3-(5-((2,3-Dichlorophenyl)thio)-6-methyl pyrazin-2-yl)-3azabicyclo[3.1.0]hexane-6-amine was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.20 (s, 1H, HCOOH), 7.85 (d, J=0.7 Hz, 1H), 7.44 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.67 (dd, J=8.0, 1.4 Hz, 1H), 3.67 (d, J=10.9Hz, 2H), 3.52-3.46(m, 2H), 2.37(d, J=0.5Hz, 3H), 2.06(t, J=2.2 Hz, 1H), 1.73-1.66 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for adD^B: 367.05; the found value is 367.35.

Example 68 Synthesis of (3R,4S)-4-(((5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)amino)methyl)piperidin-3-ol

CL Me

(3R,4S)-4-(((5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)amino)methyl)piperidin-3-ol was synthesized by a method similar to that in Example 1 , except that 2-methyl-N-((R)8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-(3R,4S)-4-(aminomethyl )-3hydroxypiperidine-1-carboxylate. (3R,4S)-4-(((5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2yl)amino)methyl)piperidin-3-ol was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.37 (s, 1H), 7.89 (d, J=0.7 Hz, 1H), 7.66 (d, J=6.1 Hz, 1H ), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.66 (dd, J=8.1, 1.4Hz, 1H), 3.84(s, 1H), 3.34-3.19(m, 2H), 3.11-2.99(m, 2H), 2.84(dd, J =12.9, 1.7 Hz, 1H), 2.71 (td, J=12.6, 3.5 Hz, 1H), 2.36 (d, J=0.6 Hz, 3H), 1 .84 (dt, J=11.8, 4.4 Hz, 1H), 1.58 (dtd, J=37.2, 13.3, 3.8 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ Cl ₂ N ₄ OS: 399.07; the found value is 399.39.

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Example 69 Synthesis of (1R,3R)-N ¹ -(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)cyclopentan-1,3diamine

(1R,3R)-N ¹ -(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)cyclopentan-1,3-diamine was synthesized by a method similar to the method in example 1, except that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-((1S,3S)-3aminocyclopentyl)carbamate.

(1R,3R)-N ¹ -(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)cyclopentan-1,3-diamine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.44 (s, 1H), 7.83 (d, J=0.7 Hz, 1H), 7.65 (d, J=6.9 Hz , 1H), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.66 (dd, J=8, 1, 1.4 Hz, 1H), 4.35 (h, J=6.6 Hz, 1H), 3.59 (p, J=6.7 Hz, 1H), 2.36 (s, 3H) , 2.20-2.11 (m, 1H), 2.11-2.02 (m, 1H), 1.99-1.91 (m, 1H), 1.85 (ddd, J=13, 6, 7.7, 5.8 Hz, 1H), 1.53 (td, J=13.7, 7.0 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₈ Cl ₂ N ₄ S: 369.06; the found value is 369.34.

Example 70 Synthesis of N-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azabicyclo[3.2.1]octan-3amine

N-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8-azabicyclo[3.2.1]octane-3-amine was synthesized by a method similar to that of Example 1, except that 2-methyl-N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide was replaced by tert-butyl-3-amino-8azabicyclo[3.2.1]octane-8- carboxylate. N-(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8azabicyclo[3.2.1]octan-3-amine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.40 (s, 1H), 7.83 (s, 1H), 7.48 (d, J=1.3 Hz, 1H), 7.43 (ddd, J=8.0, 3.2, 1.3 Hz, 1H), 7.22 (td, J=8.0, 2.9 Hz, 1H), 6.66 (ddd, J=15 .0, 8.1, 1.4 Hz, 1H), 4.14 (d, J=12.4 Hz, 1H), 3.75 (s, 2H), 2.36 (d, J=3, 6 Hz, 3H), 2.18 (t, J=10.7 Hz, 2H), 2.01-1.76 (m, 6H), 1.60 (t, J=12.2 Hz, 1H) . LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₈ H ₂₀ Cl ₂ N ₄ S: 39508; the found value is 395.4.

Example 71 Synthesis of N ¹ -(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)ethane-1,2-diamine

N ¹ -(5-((2,3-Dichlorophenyl)thio)-6-methylpyrazin-2-yl)ethan-1,2-diamine was synthesized by a method similar to the method in example 1, except that 2-methyl -N-((R)-8-azaspiro[4.5]decan1-yl)propan-2-sulfinamide was replaced by tert-butyl-(2-aminoethyl)carbamate. N ¹ -(5-((2,3Dichlorophenyl)thio)-6-methylpyrazin-2-yl)ethan-1,2-diamine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.37 (s, 1H), 7.87 (d, J=0.7 Hz, 1H), 7.85 (d, J=6.1 Hz , 1H), 7.44 (dd, J=8.0, 1.4 Hz, 1H), 7.22 (t, J=8.1 Hz, 1H), 6.67 (dd, J=8, 1, 1.4 Hz, 1H), 3.46 (q, J=6.0 Hz, 2H), 2.91 (t, J=6.2 Hz, 2H), 2.37 (d, J= 0.6 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C^CW 329.03; the found value is 329.3.

Example 72 Synthesis of 5-((2,3-dichlorophenyl)thio)-6-methyl-N-(piperazin-2-ylmethyl)pyrazin-2-amine

5-((2,3-Dichlorophenyl)thio)-6-methyl-N-(piperazin-2-ylmethyl)pyrazin-2-amine was synthesized by a method similar to the method in example 1, except that 2-methyl- N-((R)-8azaspiro[4.5]decan-1-yl)propan-2-sulfinamide (aminomethyl)piperazine-1,4-dicarboxylate.

was replaced by di-tert-butyl-25-((2,3-Dichlorophenyl)thio)-6-methyl-N-(piperazin-2ylmethyl)pyrazin-2-amine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.34 (s, 1H), 7.89 (s, 1H), 7.67 (s, 1H), 7.44 (dd, J=8, 0, 1.4 Hz, 1H), 7.22 (t, J=8.0 Hz, 1H), 6.67 (dd, J=8.1, 1.4 Hz, 1H), 3.32 ( td, J=6.1, 2.0 Hz, 2H), 3.11-2.90 (m, 4H), 2.80-2.65 (m, 2H), 2.37 (s, 3H) . LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₉ Cl ₂ N ₅ S: 384.07; the found value is 384.37.

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Example 73 Synthesis of (R)-8-(5-(2,3-dichloro-pyridin-4-yl)-6-methyl-pyrazin-2-yl)-8-azacniro[4.5]decan1-amine

(R)-8-(5-(2,3-Dichloropyridin-4-yl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was synthesized by a method similar to that of Example 23 , except that (2,3-dichlorophenyl)boronic acid was replaced by (2,3-dichloropyridin-4-yl)boronic acid. (R)-8(5-(2,3-Dichloropyridin-4-yl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-amine was isolated as its formate salt after HPLC purification . ¹ H NMR (500 MHz, DMSO-d6) δ 8.45 (d, J=4.9 Hz, 1H), 8.38 (s, 1H), 8.24 (d, J=0.7 Hz, 1H), 7.52 (d, J=4.9 Hz, 1H), 4.30-4.16 (m, 2H), 3.18-3.05 (m, 2H), 2.89 (t , J=1.2 Hz, 1H), 2.17 (d, J=0.6 Hz, 3H), 1.93 (dt, J=12.9, 6.6 Hz, 1H), 1.85 -1.77 (m, 1H), 1.73-1.41 (m, 5H), 1.40-1.25 (m, 2H), 1.10 (s, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₃ Cl ₂ N ₅ : 392.13; the found value is 392.44.

Example 74 Synthesis of 1-(5-(2,3-dichloropyridin-4-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine

-(5-(2,3-Dichloropyridin-4-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was synthesized by a method similar to that of Example 24, except that (2, 3-dichlorophenyl)boronic acid was replaced by (2,3-dichloropyridin-4-yl)boronic acid. 1-(5(2,3-Dichloropyridin-4-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d6) δ 8.46 (d, J=4.9 Hz, 1H), 8.39 (s, 1H), 8.26 (d, J=0.8 Hz, 1H), 7.52 (d, J=4.9 Hz, 1H), 3.95 (ddd, J=13.7, 6.2, 4.3 Hz, 2H), 3.52 (ddd, J =13.0, 8.2, 4.2 Hz, 2H), 2.18 (d, J=0.5 Hz, 3H), 1.69 (qt, J=12.9, 6.4 Hz, 4H), 1.31(s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₆ H ₁₉ Cl ₂ N ₅ : 352.10; the found value is 352.39.

Example 75 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dimethoxyphenyl)-5methylpyrazin-2-yl)methanol

^Me

ΟΜβΝ^Λ^ νΗ ₂ (R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dimethoxyphenyl)-5-methylpyrazin-2-yl)methanol synthesized by a method similar to the method in example 29, example 30 and example 32, except that (2,3-dichlorophenyl)boronic acid was replaced by (2,3dimethoxyphenyl)boronic acid. (R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3dimethoxyphenyl)-5-methylpyrazin-2-yl)methanol was isolated as its formate salt after HPLC purification . ¹ H NMR (500 MHz, Methanol^) δ 8.57 (s, 1H), 7.19 (dd, J=8.2, 7.5 Hz, 1H), 7.14 (dd, J=8, 3, 1.7 Hz, 1H), 6.90 (dd, J=7.5, 1.7 Hz, 1H), 4.70 (s, 2H), 3.93 (s, 3H), 3, 72-3.61 (m, 2H), 3.61 (s, 3H), 3.21 (t, J=6.8 Hz, 1H), 3.13 (tdd, J=12.0, 2, 9, 1.6 Hz, 2H), 2.29 (s, 3H), 2.27-2.14 (m, 1H), 1.98-1.76 (m, 5H), 1.72 (dt , J=12.7, 6.5 Hz, 1H), 1.63-1.52 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₃ H ₃₂ N ₄ O ₃ : 413.25; the found value is 413.60.

Example 76 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2-chloro-6-methoxypyridin-3-yl)5-methylpyrazin-2- yl) methanol.

(R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2-chloro-6-methoxypyridin-3-yl)-5-methylpyrazin-2yl)methanol was synthesized via a method similar to the method in example 29, example 30 and example 32, except that (2,3-dichlorophenyl)boronic acid was replaced by (2-chloro-6methoxypyridin-3-yl)boronic acid. (R)-(3-(1-Amino-8-azacniro[4.5]decan-8-yl)-6-(2-chloro-6methoxypyridin-3-yl)-5-methylpyrazin-2-yl)methanol was isolated in in the form of its formate salt after HPLC purification. ¹ H NMR (500 MHz, Methanol-d4) δ 8.57 (s, 1H), 7.73 (d, J=8.3 Hz, 1H), 6.90 (d, J=8.3 Hz, 1H), 4.69

- 141 041617 (s, 2H), 3.99 (s, 3H), 3.71 (dd, J=26.0, 13.2 Hz, 2H), 3.18-3.08 (m, 3H) , 2.31 (s, 3H), 2.24-2.14 (m, 1H), 1.89 (ddq, J=17.3, 9.0, 4.5 Hz, 3H), 1.84 -1.72 (m, 3H), 1.71-1.61 (m, 1H), 1.54 (dd, J=24.8, 13.0 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₂ : 418.19; the found value is 418.56.

Example 77 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichloropyridin-4-yl)-5methylpyrazin-2-yl)methanol .

(R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichloropyridin-4-yl)-5-methylpyrazin-2yl)methanol was synthesized by the method similar to the method in example 29, example 30 and example 32, except that (2,3-dichlorophenyl)boronic acid was replaced by (2,3dichloropyridin-4-yl)boronic acid. (R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichloropyridin-4-yl)-5-methylpyrazin-2-yl)methanol was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, Methanol-d ₄ ) δ 8.57 (s, 1H), 8.43 (d, J=4.8 Hz, 1H), 7.47 (d, J=4.8 Hz, 1H), 4.70 (s, 2H), 3.84 (t, J=6.8 Hz, 1H), 3.78 (d, J=13.5 Hz, 1H), 3.23 (t, J=6.9 Hz, 1H), 3.20-3.12(m, 2H), 2.30(s, 3H), 2.27-2.19(m, 1H), 1.96-1 .68 (m, 7H), 1.65-1.51 (m, 2H), 1.20 (s, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₅ Cl ₂ N ₅ O: 422.14; the found value is 422.41.

Example 78 Synthesis of (R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-N-hydroxy-5methylpyrazine-2-carboxamide

[Γ^Ί ^Me sADC ^{C1 ν} /νΛ ?<n ₂ ηνΑ A A OH (R)-3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl )-N-hydroxy-5-methylpyrazine-2carboxamide was synthesized by a method similar to the method in example 30, except that the ammonium acetate was replaced by hydroxylamine. (R)-3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6(2,3-dichlorophenyl)-N-hydroxy-5-methylpyrazine-2-carboxamide was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.39 (s, 1H), 7.72 (dd, J=8.0, 1.6 Hz, 1H), 7.47 (t, J=7 .8 Hz, 1H), 7.41 (dd, J=7.6, 1.6 Hz, 1H), 4.01-3.86 (m, 2H), 3.17-3.06 (m, 2H), 2.91 (t, J=6.9 Hz, 1H), 2.18 (s, 3H), 2.02-1.89 (m, 1H), 1.83-1.73 (m , 1H), 1.73-1.41 (m, 5H), 1.31 (dd, J=36.2, 13.3 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₅ Cl ₂ N ₅ O ₂ : 450.14; the found value is 450.53.

Example 79 Synthesis of (3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl)(2-(hydroxymethyl )pyrrolidin-1-yl)methanone.

(3-((R)-1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)(2(hydroxymethyl)pyrrolidin- 1-yl)methanone was synthesized by a method similar to the method in example 30, except that the ammonium acetate was replaced by pyrrolidin-2-ylmethanol. (3-((R)1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)(2(hydroxylmethyl)pyrrolidin-1 -yl)methanone was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.37 (s, 1H), 7.72 (dt, J=7.9, 1.4 Hz, 1H), 7.47 (td, J=1 .8, 3.8 Hz, 1H), 7.447.38 (m, 1H), 4.12-3.94 (m, 2H), 3.88 (dd, J=26.8, 13.4 Hz, 1H), 3.67 (dd, J=10.3, 3.7 Hz, 1H), 3.44-3.32 (m,

3H), 3.17-3.03 (m, 2H), 2.87 (q, J=6.6 Hz, 1H), 2.18 (d, J=1.2 Hz, 3H), 1, 92 (dq, J=13.5, 5.5, 4.7 Hz, 5H), 1.77 (dt, J=12.7, 8.6 Hz, 2H), 1.71-1.52 ( m, 1H), 1.52-1.38 (m, 1H), 1.30 (dd, J=32.6, 13.2 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₆ H ₃₃ Cl ₂ N ₅ O ₂ : 518.20; the found value is 518.55.

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Example 80 Synthesis of 3-((R)-1-amino-8-αzaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methyl-N(tetrahydrofuran-3-yl) pyrazine-2-carboxamide.

3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methyl-N-(tetrahydrofuran-3-yl)pyrazin-2 α-carboxamide was synthesized by a method similar to the method in example 30, except that the ammonium acetate was replaced by tetrahydrofuran-3-ol. 3-((R)-1-Amuho-8αzaspiro[4.5]decαn-8-yl)-6-(2,3-dichlorophenyl)-5-methyl-N-(tetrahydrofuran-3-yl)pyrazine-2-carboxαmide isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 10.95 (d, J=6.6 Hz, 1H), 10.66 (s, 1H), 10.01 (dd, J=7.9, 1 .7 Hz, 1H), 9.76 (t, J=7.8 Hz, 1H), 9.72 (dd, J=7.6, 1.7 Hz, 1H), 6.70-6.59 (m, 1H), 6.21-6.03 (m, 5H), 5.97 (td, J=8.1, 5.8 Hz, 1H), 5.84 (ddd, J=8.9 , 4.2, 1.7 Hz, 1H), 5.39 (t, J=12.7 Hz, 2H), 5.17 (t, J=7.0 Hz, 1H), 4.47 (s , 3H), 4.41 (dq, J=12.6, 7.7 Hz, 1H), 4.28-4.11 (m, 2H), 4.10-4.01 (m, 1H), 4.01-3.66 (m, 4H), 3.59 (dd, J=32.2, 13.4 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₃₁ Cl ₂ N ₅ O ₂ : 504.19; the found value is 504.56.

Example 81 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decαn-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl)(3-hydroxy- 3-(trifluoromethyl)azetidin-1-yl)methanone.

(R)-(3-(1-Amino-8-αzaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)(3-hydroxy3-(trifluoromethyl )azetidin-1-yl)methanone was synthesized by a method similar to the method in example 30, except that the ammonium acetate was replaced by 3-(trifluoromethyl)azetidin-3-ol.

(R)-(3-(1-Amino-8-αzaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)(3-hydroxy3-(trifluoromethyl )azetidin-1-yl)methanone was isolated as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d6) δ 8.38 (s, 1H), 7.73 (dd, J=7.3, 2.3 Hz, 1H), 7.51-7.44 (m, 2H), 4.34 (dd, J=10.6, 6.0 Hz, 1H), 4.27 (dt, J=11.2, 1.3 Hz, 1H), 4.23 (d, J =10.7 Hz, 1H), 4.04 (d, J=11.2 Hz, 1H), 3.82 (dt, J=47.5, 15.2 Hz, 2H), 3.19-3 .04 (m, 2H), 2.91 (t, J=1.0 Hz, 1H), 2.20 (s, 3H), 1.93 (dt, J=16.6, 6.7 Hz, 1H), 1.83-1.40 (m, 5H), 1.40-1.25 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₂₈ Cl ₂ F ₃ N ₅ O ₂ : 558.16; the found value is 558.51.

Example 82 Synthesis of 6-(4-(aminomethyl)-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazine-2carbonitrile

6-(4-(Aminomethyl)-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)pyrazine-2-carbonitrile was synthesized by a method similar to that of Example 26, except that t-butyl -(4methylpiperidin-4-yl)carbamate was replaced by tert-butyl-((4-methylpiperidin-4yl)methyl)carbamate hydrochloride. ¹ H NMR (500 MHz, chloroform-d) δ 8.37 (s, 1H), 7.60 (dd, J=7.6, 2.0 Hz, 1H), 7.42-7.30 (m , 2H), 4.07-4.02 (m, 2H), 3.54-3.48 (m, 2H), 2.89 (s, 2H), 1.77-1.55 (m, 4H ), 1.27 (s, 3H). LC-MS (ESI):

mass/charge: [M+N] calc. for C ₁₈ H ₁₉ Cl ₂ N ₅ : 376.10; the found value is 376.38.

Example 83 Synthesis of 4-amino-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-N-(tetrahydro-2Hpyran-4-yl)piperidine-4-carboxamide.

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Step 1. Synthesis of methyl 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-yl)piperidine-4-carboxylate.

The vial was loaded with 5-chloro-2-((2,3-dichlorophenyl)thio)-3-methylpyrazine (450 mg, 1.47 mmol, 1 eq), 4-N-Boc-aminopiperidine-4 methyl ester hemioxalate -carboxylic acid (667 mg, 2.20 mmol, 1.5 eq.), diisopropylethylamine (894 μl, 5.14 mmol, 3.5 eq.), DMA (7.35 ml) and a magnetic stirrer to obtain a heterogeneous mixture . The vial was placed in a heating block at 100°C and stirred for 16 h, after which the cooled reaction mixture was poured into ethyl acetate (15 ml) and water (15 ml). The separated organic phase was washed with water (1x15 ml) and the combined aqueous phases were re-extracted with ethyl acetate (1x10 ml). The combined organics were washed successively with citric acid (0.2N, 3x20 ml), water (1x20 ml) and brine (1x20 ml). The washed organic solution was dried over MgSO ₄ , filtered and concentrated under reduced pressure to give methyl 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-yl )piperidine-4-carboxylate (739 mg, 95%) as a yellow foam, which was used directly in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₃ H ₂₈ Cl ₂ N ₄ O ₄ S: 527.12; the found value is 527.35.

Step 2 Synthesis of 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)piperidine-4-carboxylic acid.

To a solution of methyl 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)piperidine-4-carboxylate (737 mg, 1.39 mmol , 1 eq.) in tetrahydrofuran (7.2 ml) was added sodium hydroxide (2 N., 2.08 ml, 4.17 mmol, 3 eq.). The resulting solution was stirred at room temperature for one hour before it was heated to 50° C. and stirred for 3.5 hours. HCl and then added water (25 ml) and ethyl acetate (25 ml). The layers were separated and the aqueous phase was successively extracted with ethyl acetate (2x15 ml) and dichloromethane (2x15 ml). The combined organic extracts were dried over MgSO ₄ , filtered and concentrated under reduced pressure to give 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-yl)piperidine -4-carboxylic acid (600 mg, 84%) as a light beige solid, which was used in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₆ Cl ₂ N ₄ O ₄ S: 513.11; the found value is 513.44.

Step 3. Synthesis of tert-butyl-(1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-((tetrahydro2H-pyran-4-yl)carbamoyl)piperidine- 4-yl) carbamate.

The vial was charged with tetrahydro-2H-pyran-4-amine (14.4 mg, 0.1427 mmol, 1.2 eq.), 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3- dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidine-4-carboxylic acid (61.1 mg, 0.1190 mmol, 1.0 eq.), diisopropylethylamine (45.5 µl, 0.2618 mmol, 2 .2 eq.), DMA (1.19 ml) and a magnetic stirrer. To this solution was added HATU (54.2 mg, 0.1427 mmol, 1.2 eq.) and the resulting mixture was stirred for 6 hours. At the end of this time, the reaction mixture was diluted with water (15 ml) and ethyl acetate (15 ml ). The layers were separated and the organic phase was washed successively with 0.2N hydrochloric acid. HCl (3x10 ml), water (1x10 ml) and saline (3x10 ml). The washed solution was then dried over MgSO4, filtered and concentrated to give tert-butyl-(1-(5-((2,3dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-((tetrahydro-2H-pyran- 4-yl)carbamoyl)piperidin-4yl)carbamate (63 mg, 88%) as a clear film, which was used directly in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₇ H ₃₅ Cl ₂ N ₅ O ₄ S: 596.18; the found value is 596.55.

Step 4. Synthesis of 4-amino-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-N-(tetrahydro-2Hpyran-4-yl)piperidine-4-carboxamide.

To a solution of tert-butyl-(1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-4-((tetrahydro-2Hpyran-4-yl)carbamoyl)piperidine-4- yl)carbamate (63 mg, 0.1056 mmol, 1 eq.) in dioxane (1 ml) HCl in dioxane (4 N, 2 ml) was added. The resulting solution was heated to 50° C. and stirred for 30 minutes. The mixture was then concentrated under reduced pressure, and the crude product was purified by preparative HPLC to give 4-amino-1-(5-((2,3-dichlorophenyl)thio)-6methylpyrαzin-2-yl)-N-(tetrahydro-2H- παn-4-ul) π-piperidine-4-carboxamide (20 mg, 38%). ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.25 (s, 1H), 7.89 (d, J=8.0 Hz, 1H), 7.47 (dd, J=8.0, 1.4 Hz, 1H), 7.25 (t, J=8.0 Hz, 1H), 7.47 (dd, J=8.0, 1.4 Hz, 1H), 7.25 (t, J=13.4, 4.0 Hz, 2H), 3.83(m, 2H), 3.78-3.69(m, 1H), 3.43-3.35(m, 4H), 2 .39(s,

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3H), 1.93(m, 2H), 1.71-1.63(m, 2H), 1.53-1.33(m, 4H). LC-MS (ESI): mass/charge: [M+H] calc. For

C ₂₂ H ₂₇ Cl ₂ N ₅ O ₂ S: 49 6.13; the found value is 496.56.

Example 84 Synthesis of 4-amino-N-cyclobutyl-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)piperidine-4-carboxamide

Me

4-Amino-N-cyclobutyl-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidine-4carboxamide was synthesized by a method similar to that of Example 83, except that tetrahydro-2H-pyran-4-amine has been replaced by cyclobutanamine hydrochloride. ¹ H NMR (500 MHz,

DMSO-d ₆ ) δ 8.24 (s, 1H), 8.13 (d, J=8.1 Hz, 1H), 7.47 (dd, J=8.0, 1.4 Hz, 1H) , 7.25 (t, J=8.0 Hz, 1H), 6.74 (dd, J=8.0, 1.4 Hz, 1H), 7.25 (t, J=13.4 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₅ Cl ₂ N ₅ OS: 466.12; the found value is 466.52.

4-Amino-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidine-4 Example 85 Synthesis of carboxamide.

tert-Butyl-(4-carbamoyl-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2 Step 1. Synthesis of yl)piperidin-4-yl)carbamate.

The vial was loaded with 4-((tert-butoxycarbonyl)amino)-1-(5-((2,3-dichlorophenyl)thio)-6methylpyrazin-2-yl)piperidine-4-carboxylic acid (100 mg, 0.1947 mmol , 1 eq.), DMA (1.94 ml) and a magnetic stirrer. The resulting solution was cooled in an ice bath and 1,1'carbonyldiimidazole (47.3 mg, 0.2920 mmol, 1.5 eq.) was added. After 30 minutes, ammonium acetate (75.0 mg, 0.9735 mmol, 5 eq.) was added and the solution allowed to warm to room temperature. Additional CDI (31 mg, 0.194 mmol, 1 eq.) and ammonium acetate (38 mg, 0.4930 mmol, 2.5 eq.) were added after 3.5 h. After 72 h, the reaction mixture was diluted with water (15 ml) and ethyl acetate (15 ml). The layers were separated, and the organic phase was successively washed with 0.2 N hydrochloric acid. HCl (3x10 ml), water (1x10 ml), sat. NaHCO ₃ (1x10 ml) and saline (1x10 ml). The washed organic solution was then dried over MgSO ₄ , filtered and concentrated under reduced pressure. The crude residue was then purified by silica gel chromatography to give tert-butyl-(4-carbamoyl-1-(5((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidin-4-yl)carbamate (51 mg, 51%) as a white solid. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₇ Cl ₂ N ₅ O ₃ S: 512.12; the found value is 512.40.

Step 2. Synthesis of 4-amino-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidine-4carboxamide.

To a solution of tert-butyl-(4-carbamoyl-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)piperidin4-yl)carbamate (51 mg, 0.09952 mmol, 1 equiv.) in dioxane (1 ml) HCl in dioxane (4N, 2 ml) was added. The resulting solution was then heated to 50° C. and stirred for 30 minutes. The mixture was then cooled and concentrated under reduced pressure. The crude residue was then purified by preparative HPLC to give 4-amino-1-(5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)piperidine-4-carboxamide (26 mg, 64%) as its formate salt. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.25 (s, 1H), 8.20 (s, 1H), 7.50-7.40 (m, 2H), 7.25 (t, J =8.0Hz, 1H), 7.02(s, 1H), 6.74(dd, J=8.0, 1.4Hz, 1H), 4.16-4.03(m, 2H) , 3.46-3.31 (m, 2H), 2.39 (s, 3H), 1.92 (ddd, J=13.4, 11.6, 4.4 Hz, 2H), 1.45 (d, J=13.5 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₁₉ Cl ₂ N ₅ OS: 412.07; the found value is 412.42.

Example 86 Synthesis of (R)-2-((3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl )amino)ethane-1-ol.

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Stage 1. Synthesis of tert-butyl-(R)-(8-(5-((2,3-dichlorophenyl)thio)-3-((2-hydroxyethyl)amino)-6methylpyrazin-2-yl)-8-azaspiro [4.5]decan-1-yl)carbamate.

To a solution of tert-butyl-(R)-(8-(3-bromo-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl) carbamate (50 mg, 0.08299 mmol, 1 eq.) in N,N-dimethylacetamide (2 ml) DIPEA (13.7 μl, 0.08299 mmol, 1 eq.) was added at 20° C. under an inert atmosphere. The resulting mixture was then heated to 120° C. and stirred for 12 hours. After this time, the reaction mixture was cooled and concentrated under reduced pressure to give t-butyl-(R)-(8-(5((2,3- dichlorophenyl)thio)-3-((2-hydroxyethyl)amino)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (40 mg, 0.0687 mmol) as light yellow solid, which was used in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₇ H ₃₇ Cl ₂ N ₅ O ₃ S: 582.20; the found value is 582.63.

Stage 2. Synthesis of (R)-2-((3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl )amino)ethan-1-ol.

To a solution of tert-butyl-(R)-(8-(5-((2,3-dichlorophenyl)thio)-3-((2-hydroxyethyl)amino)-6methylpyrazin-2-yl)-8-azaspiro[4.5 ]decan-1-yl)carbamate (40 mg, 0.0687 mmol, 1 eq.) in MeOH (2 ml) was added HCl (4.0 M in dioxane, 1 ml). The resulting mixture was stirred at 20° C. for 1 hour. Then, the reaction mixture was concentrated under reduced pressure, and the crude residue thus obtained was purified by preparative HPLC to obtain (R)-2-((3-(1-amino8-azaspiro [4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5-methylpyrazin-2-yl)amino)ethan-1-ol (3.0 mg, 7.5% yield) in the form of a solid. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.44 (s, 1H), 7.82 (d, J=0.7 Hz, 1H), 7.59 (d, J=6.7 Hz, 1H), 7.43 (dd, J=8.0, 1.4 Hz, 1H), 3.72-3.61 (m, 2H), 3.61 (m, 2H), 3.56 (t , J=6.8 Hz, 1H), 3.45 (tdd, J=12.0, 2.9, 1.6 Hz, 2H), 2.29 (s, 3H), 2.27-2, 14 (m, 1H), 1.98-1.76 (m, 5H), 1.72 (dt, J=12.7, 6.5 Hz, 1H), 1.63-1.52 (m, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C22H29Cl2N ₅ OS: 482.15; the found value is 482.53.

Example 87 Synthesis of (R)-2-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl) propan-2-ol.

A solution of tert-butyl-(8-(3-bromo-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (22 mg, 36.5 μmol, 1 eq.) was dissolved in THF (0.3 ml) and cooled to -25°C, and a complex of isopropyl magnesium chloride and lithium chloride (1.3 M in THF, 5 6.1 μl, 7 3.0 µmol, 2 eq.). After this addition was completed, the reaction mixture was heated to 0°C for 2.5 hours. After this time, the solution was cooled to -25°C and another portion of the complex of isopropyl magnesium chloride and lithium chloride (1.3 M in THF, 56.1 µl, 73.0 µmol, 2 eq.). The resulting mixture was heated to -15°C for 1 h, after which acetone (26.7 μl, 365 μmol, 10 eq.) was added and the reaction mixture was heated to 0°C. After 1 hour, the mixture was poured into an aqueous solution of NaHCO ₃ (5 ml) and was extracted with EtOAc (5x2 ml). The combined organic extracts were passed through a plug of silica gel (eluted with EtOAc) and the filtrate was concentrated under reduced pressure. The resulting crude residue was dissolved in MeOH (2 ml) and HCl (4 M in dioxane, 1 ml) was added. The reaction mixture was stirred at room temperature for 2 hours. At the end of this time, the solvent was removed under reduced pressure and the crude product was purified by preparative HPLC to give (R)-2-(3-(1-amino-8azaspiro[4.5]decan- 8-yl)-6-((2,3-dichlorophenyl)thio)-5-methylpyrazin-2-yl)propan-2-ol (3.9 mg, 22% yield) as a white amorphous solid. (R)-2-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3dichlorophenyl)thio)-5-methylpyrazin-2-yl)propan-2- ol was isolated as its formate salt. 1H NMR (500 MHz, Methanol-d^ δ 8.60 (s, 1H), 7.66 (dd, J=8.1, 1.5 Hz, 1H), 7.61 (dd, J=7, 8, 1.5 Hz, 1H), 7.37 (t, J=7.9 Hz, 1H), 3.24-3.14 (m, 3H), 3.05-2.96 (m, 2H ), 2.56 (s, 3H), 2.23 (t, J=7.5 Hz, 1H), 2.10-2.02 (m, 1H), 1.93-1.52 (m, 8H), 1.26 (d, J=1.2 Hz, 6H) LC-MS (ESI): mass/charge: [M+H] calcd for C ₂₃ H ₃₀ Cl ₂ N ₄ OS: 481 .15, found value 481.47.

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Example 88 Synthesis

1-(3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl)ethan-1-ol.

Step 1. Synthesis of tert-butyl-(R)-(8-(5-(2,3-dichlorophenyl)-3-(methoxy(methyl)carbamoyl)-6methylpyrazin-2-yl)-8-azaspiro[4.5]decane -1 -yl) carbamate.

To a solution of (R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazine-2-carboxylic acid ( 66 mg, 123 µmol, 1 eq.) in DCM (0.5 ml) at 23° C. N,O-dimethylhydroxylamine hydrochloride (13.9 mg, 143 µmol, 1.2 eq.), hexafluorophosphate 1-[ bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium-3-oxide (54.3 mg, 143 µmol, 1.2 eq) and diisopropylethylamine (64.3 µl , 369 µmol, 3 eq.). The resulting mixture was stirred for 40 minutes before water (3 ml) and brine (3 ml) were added and the aqueous phase was extracted with EtOAc (5x2 ml). The combined organic extracts were passed through a plug of silica gel and the filtrate was concentrated under reduced pressure. The resulting crude material (75 mg) was used in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₈ H ₃₇ Cl ₂ N ₅ O ₄ : 578.22; the found value is 578.56.

Step 2. Synthesis of tert-butyl-(R)-(8-(3-acetyl-5-(2,3-dichlorophenyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate .

Solution of crude tert-butyl-(8-(5-(2,3-dichlorophenyl)-3-(methoxy(methyl)carbamoyl)-6methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (75 mg, 129 μmol, 1 eq.) in tetrahydrofuran (2 ml) was cooled to -78°C. After cooling, methylmagnesium bromide (3 M in diethyl ether, 215 μl, 645 μmol, 5 eq.) was added dropwise and the reaction mixture was heated to 0°C. After stirring for 45 min, an aqueous solution of ammonium chloride (10 ml) was added and the resulting biphasic mixture was extracted with EtOAc (5x3 ml). The combined organic fractions were passed through a plug of silica gel and concentrated under reduced pressure. The crude material thus obtained (13 mg) was used in the next step without further purification. LCMS (ESI): mass/charge: [M+H] calc. for C ₂₇ H ₃₄ Cl ₂ N ₄ O ₃ : 533.20; the found value is 533.57.

Stage 3. Synthesis of 1-(3-((R)-1-amino-8-azacniro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl)ethan-1 -ola.

Solution of (R)-tert-butyl-(8-(3-acetyl-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (13 mg, 22.9 μmol, 1 eq.) in MeOH (0.45 ml) was cooled to 0°C. After cooling, sodium borohydride (2.59 mg, 68.6 µmol, 3 eq) was added in one portion and the resulting mixture was stirred for 15 minutes. After this time, a saturated aqueous solution of NaHCO ₃ (5 ml) was added and the resulting biphasic mixture was extracted with EtOAc (5x2 ml). The combined organic extracts were passed through a plug of silica gel (eluted with EtOAc) and the filtrate was concentrated under reduced pressure. The resulting residue was dissolved in MeOH (2 ml) and HCl (4 M in dioxane, 1 ml) was added. The resulting mixture was stirred at room temperature for 2 hours, after which the solvent was removed under reduced pressure. The crude residue thus obtained was purified by preparative HPLC to give 1-(3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine -2-yl)ethan-1-ol (2.0 mg, 4% yield over three steps) as a white amorphous solid. 1-(3-((R)-1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)ethan-1-ol isolated as its formate salt. ¹ H NMR (500 MHz, methanol-d ₄ ) δ 8.58 (s, 1H), 7.66 (dd, J=7.9, 1.5 Hz, 1H), 7.44 (t, J= 7.8 Hz, 1H), 7.37 (dd, J=7.6, 1.6 Hz, 1H), 5.16 (q, J=6.4 Hz, 1H), 3.74 (dd, J=24.3, 10.8 Hz, 1H), 3.57-3.47 (m, 1H), 3.29-3.25 (m, 1H), 3.24-3.18 (m, 1H), 3.11 (s, 1H), 2.29 (s, 3H), 2.28-2.20 (m, 2H), 2.01-1.71 (m, 6H), 1.61 (q, J=14.8, 13.7 Hz, 2H), 1.53 (d, J=6.3 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₈ Cl ₂ N ₄ O: 435.16; the found value is 435.51.

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Example 89.

Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-(3-chloro-2-methoxypyridin-4-yl)-5methylpyrazin-2-yl)methanol.

Pd(dppf)CI ₂ *DCM to ₂ from ₃

MeSPN^O

100°С

Stage 1. Synthesis of ethyl 5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate.

Ethanol (216 ml) and propane-1,2-diamine (11.1 ml, 131 mmol, 1.01 eq.) were charged to a 500 ml vial and the resulting clear colorless solution was cooled to 0°C. After cooling, diethyl 2-oxomalonate (20 ml, 130 mmol, 1.0 eq.) was added dropwise to the solution, the cooling bath was removed and the reaction mixture was allowed to warm to room temperature. After stirring for 2 hours, the clear, colorless solution became a thick milky white mixture. At this time, the vial was provided with a reflux condenser and the reaction mixture was heated to 95°C. The reaction mixture was then allowed to stir for 24 hours, after which the solution was cooled to room temperature and concentrated under reduced pressure to give a dark orange oil. This oil was then diluted with a minimum amount of DCM and passed through a plug of silica gel and the filtrate containing the desired product was concentrated under reduced pressure to give a bright orange solid. This solid was triturated with MTBE to give ethyl 5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate (4.27 g, 23.4 mmol, 18%) as a salmon colored solid. 1H NMR (500 MHz, DMSO-d6) δ 7.35 (br s, 1H), 4.26 (q, J=7.1 Hz, 2H), 2.24 (s, 3H), 1.27 ( t, J=7.1 Hz, 3H).

Stage 2. Synthesis of ethyl 6-bromo-5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate.

A 500 ml vial was charged with ethyl 5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate (3 g, 16.4 mmol, 1 eq.) and DMF (65.6 ml) under an inert atmosphere and obtained as a result, the solution was cooled to 0°C. After cooling, NBS (3.06 g, 17.2 mmol, 1.05 eq.) was added in one portion and the cooling bath was removed. After stirring for 1 h, the reaction mixture was diluted with water (150 ml) and ethyl acetate (200 ml). The layers were separated and the resulting organic solution was then washed successively with water (150 ml), 1/2 brine (2x150 ml) and brine (2x150 ml). The organic solution was then dried over magnesium sulfate, filtered and concentrated to give ethyl 6-bromo-5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate (3.77 g, 14.4 mmol, 88.0 %) as a pale yellow solid. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 4.30 (q, J=7.1 Hz, 2H), 2.49-2.41 (br s, 3H), 1.29 (t, J =7.1 Hz, 3H).

Stage 3. Synthesis of ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate.

A 500 ml vial was charged with triphenylphosphine (18.0 g, 68.7 mmol, 3 eq.) and 1,4-dioxane (228 ml) to give a clear colorless solution. N-chlorosuccinimide (9.32 g, 69.8 mmol, 3.05 eq) was then added to this solution and the resulting mixture was allowed to stir for 30 minutes. After this time, the solution became a thick white suspension. Ethyl 6-bromo-5-methyl-3-oxo-3,4-dihydropyrazine-2-carboxylate (6 g, 22.9 mmol, 1 eq) was then added to this slurry in one portion and the resulting mixture was heated to 100° C. and allowed to stir for 1 hour. After this time, the mixture turned brown/black. The reaction mixture was then cooled to room temperature, triethylamine (57 ml) was added and the resulting mixture was concentrated to a thick black oil. This crude material was dissolved in DCM and passed through a plug of silica gel to give an oily brown solid. This solid was further purified by silica gel chromatography to give ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (5.20 g, 18.6 mmol, 81.2%) as an orange oil which slowly crystallized to provide an orange solid. 1 H NMR (500 MHz, chloroform-d) δ 4.50-4.45 (m, 2H), 2.72 (s, 3H), 1.43 (t, J=7.1 Hz, 3H).

Stage 4. Synthesis of ethyl 3-chloro-6-(3-chloro-2-methoxypyridin-4-yl)-5-methylpyrazin-2-carboxylate.

(3-Chloro-2-methoxypyridin-4-yl)boronic acid (209 mg, 1.12 mmol, 1.5 eq.), potassium carbonate (415 mg, 3.01 mmol, 4 eq.), [1, 1'-bis(diphenylphosphino)ferrocene]dichloropalladium(11), complex with dichloromethane (122 mg, 150 µmol, 0.2 eq.) and methyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (200

- 148041617 mg, 753 µmol, 1 eq.) were weighed into a 40 ml vial equipped with a magnetic stirrer and a septum screw cap. The reaction vessel was then placed under an inert atmosphere and degassed MeCN (7.52 ml) and water (50 μl) were added to the vial. The mixture was placed in a heating block preheated at 100° C. and stirred vigorously for 1 hour. After this time, the crude reaction mixture was filtered through a plug of silica gel (eluting with EtOAc). The filtrate was concentrated under reduced pressure to give crude ethyl 3-chloro6-(3-chloro-2-methoxypyridin-4-yl)-5-methylpyrazin-2-carboxylate (555 mg), which was directly used in the next step without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₄ H ₁₃ Cl ₂ N ₃ O ₃ : 342.03; the found value is 342.22.

Stage 5. Synthesis of ethyl 3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-6-(3-chloro-2methoxypyridin-4-yl)-5-methylpyrazin-2-carboxylate .

Ethyl 3-chloro-6-(3-chloro- 2-methoxypyridin-4-yl)-5-methylpyrazine-2-carboxylate (170 mg, 518 µmol, 1 eq.) and diisopropylethylamine (45.1 µl, 259 µmol, 0.5 eq.). The mixture was then heated to 100°C and stirred for 30 min. After this time, the reaction mixture was diluted with EtOAc (10 ml) and washed successively with saturated aqueous NaHCO ₃ (15 ml), water (10 ml) and brine (10 ml). The combined aqueous washes were extracted with EtOAc (3x15 ml). The combined organic extracts were passed through a plug of silica gel and the filtrate was concentrated under reduced pressure to give crude ethyl 3(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-6-(3-chloro-2-methoxypyridine -4-yl)-5methylpyrazin-2-carboxylate (411 mg), which was used without further purification in the next step. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₃₄ ClN ₅ O ₅ : 520.22; the found value is 520.62.

Step 6 Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-(3-chloro-2-methoxypyridin-4-yl)-5methylpyrazin-2-yl)methanol.

Ethyl 3-(4-((tert-butoxycarbonyl)amino)-4-methylpiperidin-1-yl)-6-(3-chloro-2methoxypyridin-4-yl)-5-methylpyrazin-2-carboxylate solution (411 mg , 790 μmol, 1 eq.) in DCM (12 ml) was cooled to -78°C. Diisobutylaluminum hydride (2.37 ml, 2.37 mmol, 3 eq.) was added dropwise to this cooled solution. The resulting mixture was stirred at -78° C. for 10 minutes. before it was heated to 0°C and stirred for 20 min. After this time, the reaction mixture was cooled to -78°C and poured into a cold, saturated aqueous solution of Rochelle's salt (150 ml). The mixture was stirred vigorously for 1 h at room temperature and then extracted with EtOAc (5x15 ml). The combined extracts were filtered through a plug of silica gel and the filtrate was concentrated under reduced pressure. The crude residue thus obtained was dissolved in MeOH (2 ml) and HCl (4M in dioxane, 1 ml) was added. The reaction mixture was stirred at room temperature for 2 hours before the solvent was removed under reduced pressure. The crude residue was then purified by preparative HPLC to give (3-(4-amino-4-methylpiperidin-1-yl)-6-(3-chloro-2-methoxypyridin-4-yl)-5-methylpyrazin-2-yl)methanol (30.0 mg, 7% yield over three steps) as a white amorphous solid. (3-(4-Amino-4methylpiperidin-1-yl)-6-(3-chloro-2-methoxypyridin-4-yl)-5-methylpyrazin-2-yl)methanol was isolated as its formate salt. ¹ H NMR (500 MHz, DMSO-de) δ 8.39 (s, 1H), 8.25 (d, J=5.1 Hz, 1H), 7.12 (d, J=5.0 Hz, 1H), 4.54 (s, 2H), 4.04 (s, 3H), 3.61 (dd, J=12.8, 6.2 Hz, 2H), 3.39-3.34 (m , 2H), 2.24 (s, 3H), 1.74 (d, J=5.7 Hz, 4H), 1.30 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C^Cl^Oi: 378.16; the found value is 378.30.

Example 90 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(3-chloro-2-methoxypyridin-4-yl)5-methylpyrazin-2- yl) methanol.

OME

(R)-(3-(1-Amino-8-azacnuro[4.5]decan-8-ul)-6-(3-chloro-2-methoxy-uniridin-4-ul)-5-methylpyrazin-2yl)methanol was synthesized via in a manner similar to that of Example 89, except that tert-butyl-(4-methylpiperidin-4-yl)carbamate was replaced by (R)-2-methyl-N-((R)-8azaspiro[4.5]decane -1-yl)propan-2-sulfinamide. (R)-(3-(1-Amino-8-azacniro[4.5]decan-8-yl)-6-(3-chloro2-methoxypyridin-4-yl)-5-methylpyrazin-2-yl)methanol was isolated in as its formate salt after HPLC purification. 1H NMR (500 MHz, DMSO-d ₆ ) δ 8.40 (s, 1H), 8.25 (d, J=5.1 Hz, 1H), 7.13 (d, J=5.1 Hz, 1H), 7.13 (d, J=7.1 Hz, 1H), 2.23 (s, 3H), 2.03-1.27 (m, 10H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₂ : 418.19; the found value is 418.56.

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Example 91 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(2-methoxypyridin-3-yl)-5methylpyrazin-2-yl)methanol

(R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(2-methoxypyridin-3-yl)-5-methylpyrazin-2yl)methanol was synthesized by a method similar to in example 89, except that tert-butyl-(4-methylpiperidin-4-yl)carbamate and (3-chloro-2-methoxypyridin-4-yl)boronic acid were replaced by (R)-2-methyl- N-((R)-8-azaspiro[4.5]decan-1-yl)propan-2-sulfinamide and (2methoxypyridin-3-yl)boronic acid, respectively. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 8.29 (dd, J=5.0, 2.0 Hz, 1H), 7.78 (dd, J=7.3, 1.9 Hz, 1H), 7.16 (dd, J=7.3, 5.0 Hz, 1H), 4.54 (s, 2H), 3.90 (s, 3H), 3.67 (dd, J=21 .2, 13.4 Hz, 2H), 3.02 (t, J=12.6 Hz, 2H), 2.93-2.89 (m, 1H), 2.23 (s, 3H), 1 .94 (s, 1H), 1.84-1.30 (m, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₉ N ₅ O ₂ : 3 84.24; the found value is 384.29.

Example 92 Synthesis of (R)-(3-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(6-chloro-2-methoxypyridin-3-yl)5-methylpyrazin-2- yl) methanol.

^)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)-6-(6-chloro-2-methoxypyridin-3-yl)-5-methylpyrazin-2yl)methanol was synthesized by the method , similar to the method in example 89, except that tert-butyl-(4-methylpiperidin-4-yl)carbamate and (3-chloro-2-methoxypyridin-4-yl)boronic acid were replaced by (R)-2 -methyl-N-((R)-8-azaspuro[4.5]decan-1-yl)propan-2-sulfinamide and (6-chloro-2methoxypyridin-3-yl)boronic acid, respectively. (R)-(3-(1-Amino-8-azaspiro[4.5]decan-8-yl)6-(6-chloro-2-methoxypyridin-3-yl)-5-methylpyrazin-2-yl)methanol was isolated as its formate salt after HPLC purification. ¹ H NMR (500 MHz, DMSO-d6) δ 8.37 (s, 1H), 7.82 (d, J=7.7 Hz, 1H), 7.25 (d, J=7.7 Hz, 1H), 7.25 (d, J=24.2, 13.1 Hz, 2H), 2.99 (t, J=12.5 Hz, 3H), 2.95-2.90 (m, 1H ), 2.20 (s, 3H), 1.93 (d, J=18.5 Hz, 1H), 1.81-1.26 (m, 8H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₂ : 418.19; the found value is 418.49.

(R)-8-(5-((2,3-dichlorophenyl)thio)-6-(trifluoromethyl)pyrazin-2-yl)-8 Example 93 Synthesis of azaspiro[4.5]decan-1-amine.

Step 1. Synthesis of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-(trifluoromethyl)pyrazin-2-yl)-8azaspiro[4.5]decan-1 -yl)-2-methylpropan-2-sulfinamide.

(R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-iodopyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)- 2-methylpropane-2-sulfinamide (69.5 mg, 0.1086 mmol, 1 eq.), (1.10phenanthroline)(trifluoromethyl)copper(I) (67.9 mg, 0.2172 mmol, 2 eq.) and a magnetic stirrer. DMF (543 μl) was added and the vial was placed in an oil bath at 50° C. overnight. The reaction mixture was then diluted with ethyl ether (10 ml) and filtered through a Celite pad. The filtrate was concentrated and the resulting precipitate was redissolved in ethyl acetate (15 ml) and washed with water (1x10 ml) and brine (1x10 ml), dried over MgSO ₄ , filtered and concentrated under reduced pressure to give 50 mg of (R)-N -((R)-8-(5-((2,3-dichlorophenyl)thio)-6(trifluoromethyl)pyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)-2-methylpropan- 2-sulfinamide, which was directly used in the next step. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₄ H ₂₉ Cl ₂ F ₃ N ₄ OS: 581.11; the found value is 581.45.

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Step 2. Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-(trifluoromethyl)pyrazin-2-yl)-8azaspiro[4.5]decan-1-amine.

To a solution of (R)-N-((R)-8-(5-((2,3-dichlorophenyl)thio)-6-(trifluoromethyl)pyrazin-2-yl)-8azaspiro[4.5]decan-1-yl )-2-methylpropane-2-sulfinamide in dioxane (1 ml) HCl in dioxane (4 M, 3 ml) was added. The resulting solution was stirred for 45 min at 50°C. The mixture was then concentrated under reduced pressure and the crude product was purified by preparative HPLC to give (R)-8-(5-((2,3-dichlorophenyl)thio)-6-(trifluoromethyl)pyrazin-2-yl)-8azaspiro[ 4.5]decan-1-amine (1.6 mg, 3% over two steps) as its formate salt. 1H NMR (500 MHz, Methanol-J4) δ 8.57 (s, 1H), 8.40 (s, 1H), 7.45 (dd, J=8.0, 1.4 Hz, 1H), 7 .20 (t, J=8.0 Hz, 1H), 7.01 (dd, J=8.0, 1.4 Hz, 1H), 7.20 (t, J=34.8, 13.6 Hz, 2H), 3.30-3.20 (m, 2H), 3.06 (m, 1H), 2.17 (m, 1H), 2.01-1.71 (m, 5H), 1 .71-1.41 (m, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₁ Cl ₂ F ₃ N ₄ S: 477.08; the found value is 477.40.

Table 1 Examples 94-141

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EXAMPLE 103 οι. at 1| G ⁵ v^^Ύιι 1 Cl Ν- ΝΗ, A ^Ν 1 ? BUT^ \ / 446.4 EXAMPLE 104 . l cS 408.5 EXAMPLE 105 Xvc ί ΪΙ 1 ^Cl nCO he 437.1 EXAMPLE 106 ^ ^CH s O 0sh NN ^Ν 'Ο'ν'^Ί .d M5 384.2 EXAMPLE 107 G U~Sat 392.2

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- 154 041617

- 155 041617

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EXAMPLE 125 sn ₃ ni Τ' ci Ύ ν η Cl JL Jr— ΝΗ ₂ HO \ sn ₃ 414.2 EXAMPLE 126 Πε- ^ΟS 405.4 EXAMPLE 127 333, 1 EXAMPLE 128 7* ΓΥ τ\ y' Χι Ή·· Χ| 1 -NH _f α to 437.2 EXAMPLE 129 sl ζ^=ς С/ 355.6

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EXAMPLE 130 1 t p g C ¹ L ,X---NH _; 415.1 EXAMPLE 131 ---HN----. Ън ---/ 425.4 EXAMPLE 132 o }---= Q ϋ 435.2 EXAMPLE 133 % 362.1 EXAMPLE 134 Ch, nrUi yX\A/\ _r ". ^NH χν o 421.1 EXAMPLE 135 aw XX i L Jr--IN; 318.5 EXAMPLE 136 XX 1 Cl Ia ^., 1 ^ ^NH: 351.4 EXAMPLE 137 X d X X 333.5

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EXAMPLE 138 ⁰ / - ^z 9 O Z s ¹ g? 353.5 EXAMPLE 139 about oJA HA 324.1 EXAMPLE 140 OS LA t Xj n 356.0 EXAMPLE 141 XO A SK X ^N Ci N A 322.9

Synthesis of examples 113 and 139-141.

Example 113 Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1H-pyrazol-5-yl)pyrazin-2-yl)-8azaspiro [4.5] decan-1-amine.

Step 1. Synthesis of tert-butyl-((1R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1-(tetrahydro-2H-pyran2-yl)-1H- pyrazol-5-yl)pyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate.

The vial was loaded with (R)-tert-butyl-(8-(3-bromo-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl )carbamate (55 mg, 0.0913 mmol) (synthesized by a method similar to that of Example 43), 1-(tetrahydro-2H-pyran-2-yl)-5-(4,4,5,5-tetramethyl- 1,3,2-dioxaborolan-2yl)-1H-pyrazole (51 mg, 0.183 mmol), Pd(dppf)Cl ₂ -DCM (14.9 mg, 0.0183 mmol, 0.2 eq.), potassium carbonate (50.4 mg, 0.365 mmol) and CH3CN (912 µl). The resulting slurry was degassed and heated to 100° C. overnight. The reaction mixture was filtered and concentrated under reduced pressure. The crude product was purified by column chromatography to give 18 mg (29%) tert-butyl-((1R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1-(tetrahydro- 2H-pyran-2-yl)-1H-nirazol-5yl)pyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate. LC-MS (ESI): mass/charge: [M+H] calc. for C ₃₃ H ₄₂ Cl ₂ N ₆ O ₃ S: 673.2; the found value is 673.7.

Step 2. Synthesis of (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1H-pirazol-5-yl)pirazin-2-yl)-8azaspiro[4.5] decan-1-amine.

To a solution of tert-butyl-((1R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1-(tetrahydro-2H-pyran-2-yl)

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1H-pyrazol-5-yl)pyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (18 mg, 0.0267 mmol, 1 eq.) in dioxane (1 ml) was added HCl in dioxane (4N, 3 ml). The resulting solution was stirred for 1.5 h at 50° C. and concentrated under reduced pressure. The crude product was purified by preparative HPLC to give (R)-8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-(1H-pyrazol-5yl)pyrazin-2-yl)-8 -azaspiro[4.5]decan-1-amine (7.3 mg, 56%) as its formate salt. ¹ H NMR (500

MHz, DMSO-d6) δ 8.40 (s, 1H), 7.70 (br s, 1H), 7.51 (dd, J=8.0, 1.4 Hz, 1H), 7.27 ( t, J=8.0 Hz, 1H), 6.91 (dd, J=8.0, 1.4 Hz, 1H), 7.27 (t, J=13.0 Hz, 1H), 1, 21 (d, J=13.0 Hz, 1H), 1.21 (d, mass/charge: [M+H] calc. for

C ₂₃ H ₂₆ Cl ₂ N ₆ S: 489.1; found value 4 89.4.

Example 139 Synthesis of 3-amino-2-(2,3-dichlorophenyl)-5,6,7,8tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin-9-one .

Stage 1. Synthesis of 5-bromo-6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-amine.

NBS (7.7 g, 43.7 mmol, 2 eq.). The mixture was stirred at 25° C. for 1 h, after which TLC (petroleum ether: ethyl acetate=1/1) indicated the reaction was complete. The reaction mixture was concentrated and the residue was passed through a silica gel column (petroleum ether/ethyl acetate 5/1 to 1/1) to give crude 5-bromo-6-chloro-3-(2,3-dichlorophenyl)pyrazine-2-amine ( 9.00 g, crude) as a brown solid which was used without further purification. ¹ H NMR (400

MHz, CDCl3) δ 7.61 (m, 1H), 7.40-7.33 (m, 2H), 4.83 (br, 2H).

Stage 2. Synthesis of tert-butyl-(2-((6-amino-3-bromo-5-(2,3-dichlorophenyl)pyrazin-2yl)amino)ethyl)carbamate.

To a solution of the compound representing crude 5-bromo-6-chloro-3-(2,3dichlorophenyl)pyrazin-2-amine (1 g, 2.8 mmol) in dioxane (5.00 ml) was added the compound representing tert-butyl-(2-aminoethyl)carbamate (1.3 g, 8.4 mmol, 1.3 ml, 3 eq.), and DIPEA (1.4 g, 11.3 mmol, 1.9 ml, 4 equiv.). The mixture was stirred at 110°C for 4 h, after which LC-MS showed the completion of the reaction. The reaction mixture was concentrated and the crude product was purified by silica gel chromatography (petroleum ether/ethyl acetate, 5:1) to give t-butyl-(2-((6amino-3-bromo-5-(2,3-dichlorophenyl)pyrazine- 2-yl)amino)ethyl)carbamate (600 mg, 1.26 mmol, 44% yield) as a brown solid. 1H NMR (400 MHz, CDCl ₃ ) δ 7.42 (dd, J=7.60 Hz, 1H), 7.25-7.19 (m, 2H) 4.83 (br, 2H), 3.46 -3.57(m, 2H) 3.46-3.34(m, 2H) 1.39(S, 9H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₇ H ₂₀ BrCl ₂ N ₅ O ₂ : 476.0; found value 47 6.0.

Step 3 Synthesis of N ² -(2-aminoethyl)-3-bromo-5-(2,3-dichlorophenyl)pyrazine-2,6-diamine.

To a solution of a compound that is tert-butyl-(2-((6-amino-3-bromo-5-(2,3dichlorophenyl)pyrazin-2-yl)amino)ethyl)carbamate (600 mg, 1.2 mmol, 1 eq.), TFA (3 ml) was added to DCM (6 ml). The mixture was stirred at 25° C. for 2 h, after which TLC (petroleum ether: ethyl acetate=1/1) indicated the reaction was complete. The reaction mixture was concentrated, MeOH (5 ml) was added to the residue, and the pH was adjusted to 7 by adding saturated aqueous NaHCO ₃ (20 ml). The aqueous phase was extracted with ethyl acetate (3x5 ml). The combined organic phase was washed with brine (2x5 ml), dried (Na ₂ SO ₄ ), filtered and concentrated to give N ² -(2-aminoethyl)-3-bromo-5-(2,3-dichlorophenyl)pyrazine-2, 6-diamine (200 mg, 0.530 mmol, 42% yield) as a brown solid, which was used directly in the next reaction.

Stage 4. Synthesis of 3-amino-2-(2,3-dichlorophenyl)-5,6,7,8-tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin9-one.

To a solution of the compound that is N ² -(2-aminoethyl)-3-bromo-5-(2,3dichlorophenyl)pyrazine-2,6-diamine (200 mg, 0.530 mmol, 1 eq.) in dioxane (80 ml ) was added DIPEA (685 mg, 5.30 mmol, 926 μl, 10 eq.), 1,3-bis(diphenylphosphino)propane (218 mg, 0.530 mmol, 1 eq.) and Pd(OAc) ₂ (59.5 mg, 0.265 mmol, 0.5 eq.). The reaction mixture was stirred at 120° C. in CO at 2 MPa for 5 h, after which LC-MS analysis showed completion of the reaction. The reaction mixture was concentrated and the crude product was purified by preparative HPLC to give the compound, which is 3-amino-2-(2,3-dichlorophenyl)-5,6,7,8-tetrahydro-9Hpyrazino[2,3-e][ 1,4]diazepin-9-one (2.3 mg, 0.007 mmol, 1.3% yield), as its formate salt. 1H

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NMR (400 MHz, CDCl ₃ ) δ 9.02 (s, 1H), 7.54 (d, J=7.50 Hz, 1H), 7.38-7.30 (m, 2H), 4.78 (brs, 1H), 4.34 (brs,

1H), 4.12 (t, J=7.94 Hz, 2H), 3.62 (t, J=8.05 Hz, 2H). LC-MS (ESI) mass/charge: [M+H] calc. For

C ₁₃ H ₁₂ Cl ₂ N ₅ O: 324.0; the found value is 324.1.

Example 140 Synthesis of 2-((2,3-dichloropyridin-4-yl)thio)-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3e][1,4]diazepin- 9-she.

Stage

1. Synthesis of tert-butyl-(2-((5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2yl)amino)ethyl)carbamate.

A mixture of 5-chloro-2-((2,3-dichloropyridin-4-yl)thio)-3-methylpyrazine (1.5 g, 4.9 mmol, 1 eq) and tert-butyl-(2-aminoethyl)carbamate ( 4.7 g, 29.3 mmol, 4.6 ml, 6 eq.) in DIPEA (6.0 ml, 33.6 mmol, 7 eq.) and dioxane (6.0 ml) were heated to 130°C in within 8 hours TLC (petroleum ether/EtOAc=1/1) showed the completion of the reaction. The mixture was concentrated to give a residue which was purified with a silica gel column (DCM/MeOH, 30:1) to give t-butyl-(2-((5-((2,3-dichloropyridin-4-yl)thio)- 6methylpyrazin-2-yl)amino)ethyl)carbamate (1.6 g, 76% yield) as a yellow oil.

Stage 2. Synthesis of tert-butyl-(2-((3-bromo-5-((2,3-dichloropyridin-4-yl)thio)-6-methylpyrazin-2yl)amino)ethyl)carbamate.

To a solution of a compound that is tert-butyl-(2-((5-((2,3-dichloropyridin-4-yl)thio)6-methylpyrazin-2-yl)amino)ethyl)carbamate (1.6 g, 3.7 mmol, 1 eq.), NBS (1.3 g, 7.4 mmol, 2 eq.) was added to DCM (20.0 ml) and the resulting mixture was stirred at room temperature for 1 h, after whereupon TLC (petroleum ether/EtOAc=2/1) indicated completion of the reaction. The reaction mixture was concentrated to give a residue, the residue was purified with a silica gel column (petroleum ether/EtOAc=8/1) to give t-butyl-(2-((3-bromo-5-((2,3-dichloropyridine-4 -yl)thio)-6methylpyrazin-2-yl)amino)ethyl)carbamate (1.6 g, 3.1 mmol, 84% yield) as a yellow solid.

¹ H NMR (400 MHz, CDCl3) δ 7.99 (d, J=5.6 Hz, 1H), 6.47 (d, J=5.6 Hz, 1H), 6.34(br, s, 1H), 4.96 (br s, 1H), 3.60-3.46 (m, 4H), 2.45 (s, 3H), 1.45 (s, 9H).

Step 3. Synthesis of methyl 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6-((2,3-dichloropyridin-4yl)thio)-5-methylpyrazine-2-carboxylate.

To a solution of a compound that is tert-butyl-(2-((3-bromo-5-((2,3-dichloropyridin-4yl)thio)-6-methylpyrazin-2-yl)amino)ethyl)carbamate (1, 5 g, 3.0 mmol, 1 eq.), in THF (5.0 ml) and MeOH (5.0 ml) was added Pd(dppf)Cl ₂ (109 mg, 0.147 mmol, 0.05 eq.), triethylamine (894 mg, 8.8 mmol, 1.2 ml, 2.9 eq.). The resulting mixture was stirred at 50° C. in CO (50 psi) for 15 h, after which TLC (petroleum ether/EtOAc=2/1) indicated completion of the reaction. The mixture was concentrated to give a residue, the residue was purified by silica gel column chromatography (petroleum ether: ethyl acetate=5:1) to give methyl 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6-((2 ,3-Dichloropyridin-4-yl)thio)-5-methylpyrazine-2-carboxylate (700 mg, 1.4 mmol, 48% yield) as a yellow solid.

Step 4 Synthesis of 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6-((2,3-dichloropyridin-4yl)thio)-5-methylpyrazine-2-carboxylic acid.

To a solution of a compound that is methyl 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6-((2,3-dichloropyridin-4-yl)thio)-5-methylpyrazine-2-carboxylate ( 700 mg, 1.4 mmol), in MeOH (10.0 ml) and water (2.0 ml) was added LiOH-H ₂ O (180 mg, 4.3 mmol, 3 eq.). The mixture was stirred at room temperature for 4 hours, after which LC-MS analysis indicated the reaction was complete. The pH of the mixture was adjusted with 1N. HCl to about 4 and extracted with EtOAc (3x10 ml). The combined organic extracts were washed with brine (1x10 ml), dried (Na2SO4), filtered and concentrated to give 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6-((2,3-dichloropyridine-4- yl)thio)-5-methylpyrazine-2-carboxylic acid (500 mg, 1.1 mmol, 74% yield) as a yellow solid. LC-MS (ESI): mass/charge:

[M-56+N] calc. for C ₁₄ H ₁₃ Cl ₂ N ₅ O ₄ S: 418.0; found value 417.9 (M-56+H).

Step 5. Synthesis of 3-((2-aminoethyl)amino)-6-((2,3-dichloropyridin-4-yl)thio)-5-methylpyrazine-2carboxylic acid.

A mixture of a compound that is 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-6((2,3-dichloropyridin-4-yl)thio)-5-methylpyrazine-2-carboxylic acid (500 mg, 1.1 mmol, 1 eq.) in TFA (1.0 ml) and DCM (2.0 ml) were stirred at room temperature for 1 h, after which TLC (DCM/MeOH, 10:1) showed completion reactions. The mixture was concentrated to give 3-((2-aminoethyl)amino)-6-((2,3-dichloropyridin-4-yl)thio)-5-methylpyrazine-2-carboxylic acid (500 mg, 1.0 mmol, 98% yield , TFA salt) as a yellow solid.

Step 6. Synthesis of 2-((2,3-dichloropyridin-4-yl)thio)-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3e] [1,4]diazepin- 9-she.

To a solution of a compound that is 3-((2-aminoethyl)amino)-6-((2,3-dichloropyridin-4yl)thio)-5-methylpyrazine-2-carboxylic acid (50 mg, 0.102 mmol, 1 eq. ), trimethylamine (62.2 mg, 0.614 mmol, 85 μl, 6 eq.) and PYBOP (107 mg, 0.205 mmol, 2 eq.) were added to DMF (5.0 ml). The resulting mixture was stirred at room temperature for 2 hours, after which LC-MS analysis indicated the completion of the reaction. The mixture was poured into water (5 ml) and the product was extracted with EtOAc (3x5 ml). The combined organic extracts were washed with water (1x5 ml), brine (1x5 ml), dried (Na ₂ SO ₄ ) and concentrated to give the crude product, which was purified by prep HPLC to give 2-((2,3-dichloropyridine-4 -yl)thio)-3-methyl-5,6,7,8tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin-9-one (1.7 mg, 0.0042 mmol, yield 4.1%, HCOOH) as its formate salt. 1H NMR (400 MHz, CDCl ₃ ) δ 7.98 (d, J=5.6 Hz, 1H), 6.71 (d, J=5.6 Hz, 1H), 5.59-3.50 ( m, 4H), 2.44 (s, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₃ H ₁₂ Cl ₂ N ₅ OS: 356.01; the found value is 356.0.

Example 141 Synthesis of 2-(2,3-dichlorophenyl)-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3e][1,4]diazepin-9-one

Step 1. Synthesis of ethyl 3-((2-({tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2carboxylate.

To a solution of ethyl 3-chloro-5-methylpyrazine-2-carboxylate (3.00 g, 14.95 mmol, 1.00 eq.) in dioxane (30.00 ml) was added tert-butyl-(2-aminoethyl) carbamate (5.99 g, 37.38 mmol, 5.87 ml, 2.50 eq) and DIPEA (5.80 g, 44.85 mmol, 7.83 ml, 3.00 eq) at 20° C. The mixture was stirred at 120° C. for 1.5 hours. TLC (petroleum ether/EtOAc=3/1) indicated completion of the reaction. The mixture was concentrated to give the crude product, which was purified with a silica gel column (petroleum ether/EtOAc=6/1) to give ethyl 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine2 -carboxylate (2.20 g, 45%) as a yellow solid. ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.14 (s, 1H), 7.79 (s, 1H), 5.14( s, 1H), 4.40-4.45(m, 2H) , 3.63-3.67 (m, 2H), 3.37-3.39 (m, 2H), 2.40 (s, 3H), 1.41 (s, 12 H). LC-CMS (ESI) mass/charge: [M+H] calc. for C ₁₅ H ₂₅ N ₄ O ₄ : 325.1; the found value is 325.1.

Step 2. Synthesis of ethyl 6-bromo-3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2carboxylate.

To a solution of ethyl 3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2-carboxylate (1.00 g, 3.08 mmol, 1.00 eq.) in DCM ( 10.00 ml) was added NBS (822 mg, 4.62 mmol, 1.50 eq.) at 20°C, the mixture was stirred at 35°C for 1 h. TLC (petroleum ether/EtOAc=3/1, Ri =0.7) showed the completion of the reaction. The mixture was concentrated to give a residue. The residue was purified with a silica gel column (petroleum ether/EtOAc=10/1) to give ethyl 6-bromo-3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2-carboxylate ( 1.10 g, 88% yield as a yellow solid. ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.09 (s, 1H), 4.94 (s, 1H), 4.39-4.44 (m, 2H), 3.62-3.63 ( s,

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1H), 3.37-3.38 (m, 1H), 2.56 (s, 3H), 1.42 (s, 12 H). LC-MS (ESI): mass/charge: [M+H] calc. For

C ₁₅ H ₂₄ BrN ₄ O ₄ : 403.1; the found value is 403.1.

Stage 3. Synthesis of 6-bromo-3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2carboxylic acid.

To a solution of ethyl 6-bromo-3-((2-((tert-butoxycarbopyl)amipo)ethyl)amipo)-5-methylpyrazip-2carboxylate (600 mg, 1.49 mmol, 1.00 eq.) in ethanol ( 5.00 ml) was added LiOH-H ₂ O (187 mg, 4.47 mmol, 3.00 eq.) and H ₂ O (1.50 ml) at 10°C. The mixture was stirred at 35° C. for 1 hour. TLC (petroleum ether/EJAc=3/1) indicated completion of the reaction. The pH of the mixture was adjusted with 2 M HCl to approximately 4 and was extracted with EtOAc (3x15 ml). The combined organic extract was washed with brine (15 ml), dried over Na ₂ SO ₄ and concentrated to give 6bromo-3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2-carboxylic acid (400 mg, 71%) as a white solid.

Stage 4. Synthesis of 3-((2-aminoethyl)amino)-6-bromo-5-methylpyrazine-2-carboxylic acid.

Solution of 6-bromo-3-((2-((tert-butoxycarbonyl)amino)ethyl)amino)-5-methylpyrazine-2-carboxylic acid (300 mg, 0.799 mmol, 1.00 eq.) in TFA (3, 00 ml) and DCM (3.00 ml) was stirred at 20° C. for 2 hours. HPLC indicated completion of the reaction. The mixture was concentrated to give 3-((2aminoethyl)amino)-6-bromo-5-methylpyrazine-2-carboxylic acid (300 mg, 0.770 mmol, 96%) as a white solid. ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 3.80-3.82 (m, 2H), 3.18-3.21 (m, 2H), 2.58 (s, 3H).

Step 5. Synthesis of 2-bromo-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin-9-one.

To a solution of 3-((2-aminoethyl)amino)-6-bromo-5-methylpyrazine-2-carboxylic acid (2.00 g, 7.27 mmol, 1.00 eq.) in DMF (200 ml) was added triethylamine (3.68 g, 36.35 mmol, 5.04 ml, 5.00 eq.), then PYBOP (7.57 g, 14.54 mmol, 2.00 eq.) was added to the mixture at 15°C, the mixture was stirred at 35° C. for 6 hours. LC-MS indicated completion of the reaction. The mixture was concentrated and the residue was purified with a silica gel column (DCM:MeOH=40:1) to give 2-bromo-3-methyl-5,6,7,8-tetrahydro-9Hpyrazino[2,3-e][1, 4]diazepin-9-one (450 mg, 1.75 mmol, 24%) as a yellow solid. LC-MS (ESI) mass/charge: [M+H] calc. for C ₈ H ₁₀ BrN ₄ O: 257.0; the found value is 257.0.

Step 6. Synthesis of 2-(2,3-dichlorophenyl)-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin9-one.

To a solution of 2-bromo-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3-e][1,4]diazepin-9-one (150 mg, 0.583 mmol, 1.00 equiv.) in acetonitrile (4.00 ml) and water (1.00 ml) was added 2,3-dichlorophenylboronic acid (167 mg, 0.875 mmol, 1.50 equiv.), Pd(dppf)Cl ₂ -DCM (47 .65 mg, 0.058 mmol, 0.10 eq.) and K ₃ PO ₄ (371 mg, 1.75 mmol, 3.00 eq.) under N ₂ atmosphere. The mixture was heated using microwave radiation to 80°C for 1.5 h, after which LC-MS analysis showed the completion of the reaction. The mixture was extracted with EtOAc (3x10 ml), the organic washed with brine (1x10 ml), dried over Na ₂ SO ₄ and concentrated to obtain a residue. The residue was purified by preparative HPLC to give 2-(2,3-dichlorophenyl)-3-methyl-5,6,7,8-tetrahydro-9H-pyrazino[2,3-e][1,4]diazepine-9 -one (63 mg, 0.195 mmol, 33% yield) as starting material. 1H NMR (400 MHz, CDCl ₃ ) δ 7.62-7.59 (m, 1H), 7.39-7.38 (m, 1H), 3.60-3.55 (m, 4H), 2 .21 (s, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₄ H ₁₃ Cl ₂ N ₄ O: 323.04; the found value is 323.0.

Examples 142-309.

Example 142 Synthesis of 3-{5-[(1R)-1-amino-8-azaspuro[4.5]decan-8-yl]-6-(hydroxymethyl)-3methylpyrazin-2-yl}-6-chloro-2- fluorobenzonitrile.

Step 1. Ethyl-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-ul)-5methylpyrazine-2-carboxylate.

To a solution of the compound representing the HCl monosalt of (R)-8-azaspiro[4.5]decan-1-amine (31 g, 200.9 mmol) in i-PrOH (300 ml) was added the compound representing ethyl-3- chloro-5methylpyrazine-2-carboxylate (40.3 g, 200.9 mmol), and DIPEA (181.8 g, 1.4 mol, 245.0 ml). The resulting mixture was stirred at 85°C for 16 hours. After completion, the reaction mixture was concentrated to obtain the compound etul-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan- 163 041617

8-yl)-5-methylpyrazin-2-carboxylate (64 g, crude) as a yellow oil. The resulting product was used in the next step without further purification.

Step 2 Ethyl-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-5methylpyrazine-2-carboxylate.

To a solution of a compound that is ethyl-(R)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)-5methylpyrazin-2-carboxylate (64 g, 201.0 mmol) in THF ( 300 ml) Boc ₂ O (87.74 g, 401.99 mmol, 92.35 ml) and TEA (20.3 g, 201.0 mmol, 27.9 ml) were added. The resulting mixture was stirred at 25°C for 2 h and concentrated under reduced pressure. The residue was purified by column chromatography to give ethyl-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)5-methylpyrazin-2-carboxylate (66 g , crude) as a yellow oil. 1H NMR (400 MHz, CDC13) δ ppm 7.89-7.69 (m, 1H), 4.40 (q, J=7.20 Hz, 3 H) 3.87-3.66 (m, 4H ), 3.18-3.04 (m, 2H), 2.67-2.58 (m, 1H), 2.39 (s, 3H), 2.12-1.98 (m, 2H), 1.81-1.58 (m, 6H) 1.51 (s, 9H) 1.40-1.36 (m, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₂ H ₃₅ N ₄ O ₄ : 419.26; the found value is 419.4.

Step 3. tert-Butyl-(R)-(8-(3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate.

To a solution of ethyl-(R)-3-(1-((tert-butoxycarbonyl)amino)-8-azaspiro[4.5]decan-8-yl)-5methylpyrazin-2-carboxylate (48 g, 114.6 mmol) in THF (500 ml) was added LiBH ₄ (2 M, 114.6 ml) at 0°C, the resulting mixture was stirred at 40°C for 2 h, and 30 ml of water and 100 ml of MeOH were added to the reaction mixture, followed by concentration under reduced pressure. The residue was purified by column chromatography to give tert-butyl-(R)-(8-(3(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (25, 8 g, 68.5 mmol, 59.7% yield as a yellow oil. 1H NMR (400 MHz, CDC13) δ ppm 8.01-7.79 (m, 1H), 4.65-4.60 (m, 2H), 4.464.39 (m, 1H), 4.10 (q , J=7.06 Hz, 1H), 3.80-3.69 (m, 1H), 3.46 (s, 1H), 3.40-3.30 (m, 2H), 3.01- 2.87 (m, 2H), 2.66-2.52 (m, 1H), 2.46-2.29 (m, 3H), 2.10-1.99 (m, 2H), 1, 86-1.61 (m, 7H), 1.44-1.42 (m, 9H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₀ H ₃₃ N ₄ O ₃ : 377.25; the found value is 377.1.

Step 4. Synthesis of (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate.

To a solution of tert-butyl-(R)-(8-(3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (9 g, 23.9 mmol) in DCM (120 ml) was added with NBS (5.11 g, 28.69 mmol) at 0° C. over a period of 5 minutes. Upon completion, the reaction mixture was warmed to room temperature, quenched with saturated Na ₂ SO ₃ solution (50 ml), extracted with EtOAc (100 ml x2) and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan1-yl) carbamate (6.8 g, 62.9%) as a yellow oil. 1H NMR (400 MHz, CDC13) δ ppm 4.62 (s, 2H), 4.40 (br d, J=8.82 Hz, 1H), 3.76 (br d, J=8.38 Hz, 1H), 3.59 (br s, 1H), 3.36 (br t, J=12.46 Hz, 2H), 3.07-2.87 (m, 2H), 2.59-2.44 (m, 3H), 2.14-1.98 (m, 1H), 1.82 (td, J=12.57, 3.97 Hz, 1H), 1.77-1.56 (m, 5H ), 1.45 (s, 9H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₀ H ₃₂ BrN ₄ O ₃ : 455.16; the found value is 455.1.

Step 5. Synthesis of (R)-3-(5-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(hydroxymethyl)-3-methylpyrazin2-yl)-6-chloro-2- fluorobenzonitrile.

Mixture of (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (11 mg, 0.22 mmol), (4-chloro-3-cyano-2-fluorophenyl)boronic acid (53 mg, 0.26 mmol) and potassium carbonate (121 mg, 0.88 mmol) in acetonitrile (5 ml) was degassed and Pd( dppf)Cl ₂ -DCM (18 mg, 0.021 mmol). The reaction mixture was stirred at 100°C for 1 h in a sealed vessel, filtered and concentrated under reduced pressure. The residue was dissolved in 5 ml of 4N. HCl/dioxane, heated to 50°C for 1 h and concentrated under reduced pressure. Purification by preparative HPLC provided (R)-3-(5-(1-amino-8-azaspiro[4.5]decan-8-yl)-6(hydroxymethyl)-3-methylpyrazin-2-yl)-6- chloro-2-fluorobenzonitrile (12 mg, 13% yield). 1H NMR (500 MHz, MeOH-d4) δ 8.57 (s, 1H), 7.88 (t, J=8.2 Hz, 1H), 7.64 (dd, J=8.4, 0, 9 Hz, 1H), 4.70 (s, 2H), 3.79 (dd, J=29.1, 13.5 Hz, 2H), 3.16 (ddd, J=14.2, 12.0 , 3.7 Hz, 3H), 2.36 (d, J=2.2 Hz, 3H), 2.26-2.13 (m, 1H), 1.97-1.74 (m, 6H) , 1.68 (dt, J=15.1, 7.9 Hz, 1H), 1.54 (dd, J=24.1, 13.0 Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₅ ClFN ₅ O: 430.9; the found value is 430.4.

The following examples were synthesized by a method similar to the method in examples 43 and 142.

- 164 041617

Table 2 Examples 143-190

Example Structure Found M+1 EXAMPLE 143 A A 429.17 EXAMPLE 144 •A 415.24 EXAMPLE 145 ^WITH 484.1 EXAMPLE 146 A / - ^g 414.24 EXAMPLE 147 O 388.18 EXAMPLE 148 "Ha 429.2

- 165 041617

EXAMPLE 149 6g Ha Ush 450.12 EXAMPLE 150 o-C 430.23 EXAMPLE 151 Whoo 467.14 EXAMPLE 152 422.21 EXAMPLE 153 ouch, 'Ush 455.17

- 166 041617

EXAMPLE 154 Uch _¥ 446, 21 EXAMPLE 155 yys usu 435.23 EXAMPLE 156 1 Ugd- 446, 15 EXAMPLE 157 η o • f/ 439.28 EXAMPLE 158 y^Q/ He 469.12

- 167 041617

EXAMPLE 159 h? I 414.2 EXAMPLE 160 □Г ^ζ ''ί Ί —( l Ъ О 368.24 EXAMPLE 161 % / - ^g 417.2 EXAMPLE 162 // €/ 444.15 EXAMPLE 163 ⁿ ^—o O \| Q Ζ^ί A ) - r A X L 444.15

- 168 041617

EXAMPLE 164 WITH; 412.18 EXAMPLE 165 a / 451.2 EXAMPLE 166 S' Η Ο 451.16 EXAMPLE 167 Η. ο / 417.2 EXAMPLE 168 With < /' ζ X 421.15

- 169 041617

EXAMPLE 169 431.2 EXAMPLE 170 b 451.16 EXAMPLE 171 jOl 1 Zq( 412.18 EXAMPLE 172 ΰ 457.13 EXAMPLE 173 η /=\ Q ? =\ /— ^z 466.09

- 170 041617

EXAMPLE 174 Go sg US^ 439.14 EXAMPLE 175 _J 5 439.14 EXAMPLE 176 S ^: Y N X 426.06 EXAMPLE 177 >OH 'KP 393.23 EXAMPLE 178 ^with US 1 T ii f ° Yа NHj 406.11

- 171 041617

EXAMPLE 179 About r—ί Ah Wah 433.26 EXAMPLE 180 ΣΣ 1 353, 1 EXAMPLE 181 XXa Cl AA. ΝΚ %* / 403.19 EXAMPLE 182 n ch OSL qAoch - ^s ^ LQ) 394.23 EXAMPLE 183 I Ζ /5 A ώ 426.06

- 172 041617

EXAMPLE 184 1 TTL >ON ΝΗ _± 411.13 EXAMPLE 185 451.16 EXAMPLE 186 %vO dh 469.02 EXAMPLE 187 BG a 509.05 EXAMPLE 188 ABOUT nm Jl 1 At a 351.454 EXAMPLE 189 ABOUT 392.24 EXAMPLE 190 σ Y ABOUT / 433.3

Example 191 Synthesis of {3-[(1R)-1-amino-8-azaspiro[4.5]decan-8-yl]-6-(2,3-dichloro-4-methylphenyl)-5methylpyrazin-2-yl}methanol .

Mixture of (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (50 mg, 0.11 mmol), (2,3-dichloro-4-methylphenyl)boronic acid (34 mg, 0.16 mmol) and potassium carbonate (45 mg, 0.33 mmol) in ethanol (2 ml) were degassed and Pd(PPh ₃ ) ₄ (6.3 mg, 0.005 mmol). The reaction mixture was stirred at 80°C for 4 h in a sealed vessel, filtered and concentrated under reduced pressure. The residue was dissolved in 5 ml of 4N. HCl/dioxane, per

- 173 041617 heated to 40°C for 1 h and concentrated under reduced pressure. Purification by preparative HPLC provided {3-[(1K)-1-amino-8-azaspiro[4.5]decan-8-yl]-6-(2,3-dichloro-4methylphenyl)-5-methylpyrazin-2- yl} methanol (12 mg, 24.5% yield). ^: H NMR (400 MHz, MeOH-d ₄ ) δ 8.57 (s, 1H), 7.40 (dt, J=7.8, 0.8 Hz, 1H), 7.26 (d, J= 7.7 Hz, 1H), 4.69 (s, 2H), 3.72 (dd, J=26.3, 13.3 Hz, 2H), 3.193.08 (m, 3H), 2.52 ( d, J=0.7 Hz, 3H), 2.26 (d, J=l.3 Hz, 3H), 2.23-2.13 (m, 1H), 1.89 (dt, J=12 .2, 3.9 Hz, 2H), 1.85-1.72 (m, 3H), 1.68 (dt, J=15.l, 7.7 Hz, 1H), 1.54 (dd, J=24,l, 13.0Hz, 2H). LC-MS (ESI): mass/charge: [M+H] calc. for C22H28CI2N4O: 435.1; the found value is 435.4.

The following examples were synthesized using a method similar to the method in example 191. __________ Table 3. Examples 192-203 __________

Example Structure Found M+1 EXAMPLE 192 X/g BUT With X 408.2 EXAMPLE 193 7 393.3 EXAMPLE 194 =7^ o 422.3 EXAMPLE 195 ABOUT /- 406.2

- 174041617

EXAMPLE 196 e 408.1 EXAMPLE 197 z—/ o 4 394.4 EXAMPLE 198 § o g O 408.1 EXAMPLE 199 CI JL ^with| O' 1 nO^ y-χ .“4 J 436.1 EXAMPLE 200 CI ne < 1.^ Xxx aVJ Qj 436.3 EXAMPLE 201 3 z—/ V A Λ— 5=-Z 437.1 EXAMPLE 202 C' I 437.4 EXAMPLE 203 .7* 393, 1

Examples 204 and 205 Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-(4-chloro-1H-indol-6-yl)-5methylpyrazin-2-yl)methanol and 1-( 5-(4-chloro-1H-indol-6-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine.

- 175 041617

Step 1. Synthesis of gret-butyl-(1-(5-(4-chloro-1H-indol-6-yl)-3-(hydroxymethyl)-6-methylpyrazin-2yl)-4-methylpiperidin-4-yl)carbamate .

The vial was loaded with tert-butyl-(1-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-4methylpiperidin-4-yl)carbamate (50 mg, 0.120 mmol, 1 eq.), 1 -(tert-butyldimethylsilyl)-4-chloro-6(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-lH-indole (71 mg, 0.180 mmol, 1.5 eq .), tetrakis(triphenylphosphine)palladium (7 mg, 0.00602 mmol, 0.05 eq.), potassium carbonate (50 mg, 0.361 mmol, 3 eq.) and a magnetic stirrer. Degassed ethanol (800 μl) was added, the vial was capped and the headspace was evacuated and filled with nitrogen three times. The vial was placed in an 80° C. oil bath for 5 hours. The reaction mixture was filtered through a Celite pad and the filtrate was concentrated. The crude product was purified by column chromatography to give 50 mg (86%) tert-butyl-(1-(5-(4-chloro-1H-indol-6-yl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl )-4-methylpiperidin-4yl)carbamate. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₃₂ ClN ₅ O ₃ : 486.2; the found value is 486.2.

Stage 2. Synthesis of (3-(4-amino-4-methylpiperidin-1-yl)-6-(4-chloro-1H-indol-6-yl)-5-methylpyrazin2-yl)methanol and 1-(5- (4-chloro-1H-indol-6-yl)-6-methylpyrazin-2-yl)-4-methylpiperidin-4-amine.

To a solution of tert-butyl-(1-(5-(4-chloro-1H-indol-6-yl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-4methylpiperidin-4-yl)carbamate (50 mg, 0.103 mmol, 1 eq.) in dioxane (1 ml) HCl in dioxane (4N, 3 ml) was added. The resulting solution was stirred for 3.5 hours at room temperature and concentrated. The resulting mixture was purified by preparative HPLC to give two products. Compound 1: (3-(4-amino-4-methylpiperidin-1-yl)-6-(4-chloro-1H-indol-6-yl)-5methylpyrazin-2-yl)methanol as its formate salt. ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.58 (s, 1H), 7.56 (s, 1H), 7.41 (d, J=3.2 Hz, 1H), 7.31 (d, J=1.3 Hz, 1H), 6.59 (dd, J=3.2, 0.9 Hz, 1H), 4.72 (s, 2H), 3.62 (m, 2H) , 3.30 (m, 2H), 2.56 (s, 3H), 1.93 (m 4H), 1.45 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₄ ClN ₅ O: 386.2; the found value is 386.3. Compound 2: 1-(5-(4-Chloro-1H-indol-6-yl)-6methylpyrazin-2-yl)-4-methylpiperidin-4-amine as its formate salt. d4) δ 8.58 (s, 1H), 8.09 (s, 1H), 7.46 (m, 1H), 7.40 (d, J=3.2 Hz, 1H), 7.19 ( d, J=1.3 Hz, 1H), 6.58 (dd, J=3.2, 0.9 Hz, 1H), 4.03 (m, 2H), 3.55 (m, 2H), 2.49 (3, 3H), 1.79 (m, 4H), 1.41 (s, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₉ H ₂₂ ClN ₅ : 356.2; the found value is 356.3.

The following example was synthesized using a method similar to the method in examples 204 and 206.

Table 4 Example 206

- 176 041617

Example 207 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-(2methyl-1, 3-benzoxazol-6-yl)pyrazin-2-yl}methanol.

Stage 1. Synthesis of ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate.

Ethanol (216 ml) and propane-1,2-diamine (11.1 ml, 131 mmol, 1.01 eq.) were charged to a 500 ml vial and the resulting clear colorless solution was cooled to 0°C. After cooling, diethyl 2-oxomalonate (20 ml, 130 mmol, 1.0 eq.) was added dropwise to the solution, the cooling bath was removed and the reaction mixture was allowed to warm to room temperature. After stirring for 2 hours, the reaction mixture was heated to 95° C. and allowed to stir for 24 hours. The resulting mixture was cooled to room temperature and concentrated under reduced pressure to give a dark orange oil. Purification by column chromatography and trituration with MTBE provided ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate (4.27 g, 23.4 mmol, 18.0%) as a salmon colored solid. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 7.35 (br s, 1H), 4.26 (q, J=7.1 Hz, 2H), 2.24 (s, 3H), 1, 27 (t, J=7.1 Hz, 3H).

Stage 2. Synthesis of ethyl 6-bromo-3-hydroxy-5-methylpyrazine-2-carboxylate.

Ethyl 3-hydroxy-5-methylpyrazine-2-carboxylate (3 g, 16.4 mmol, 1 eq.) and DMF (65.6 ml) were charged to a 500 ml vial under nitrogen atmosphere and the resulting solution was cooled to 0 °C followed by the addition of NBS (3.06 g, 17.2 mmol, 1.05 eq.). The resulting mixture was allowed to stir for 1 hour at room temperature, then diluted with water (150 ml) and ethyl acetate (200 ml). The layers were separated and the resulting organic solution was then washed successively with water (150 ml), 1/2 brine (2x150 ml) and brine (2x150 ml). The organic solution was then dried over magnesium sulfate, filtered and concentrated under reduced pressure to give ethyl 6-bromo-3-hydroxy-5-methylpyrazine-2-carboxylate (3.77 g, 14.4 mmol, 88.0%) in as a pale yellow solid. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 4.30 (q, J=7.1 Hz, 2H), 2.49-2.41 (br s, 3H), 1.29 (t, J =7.1 Hz, 3H).

Stage 3. Synthesis of ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate.

A 500 ml vial was charged with triphenylphosphine (18.0 g, 68.7 mmol, 3 eq.) and 1,4-dioxane (228 ml). N-chlorosuccinimide (9.32 g, 69.8 mmol, 3.05 eq) was then added to this solution and the resulting mixture was allowed to stir for 30 minutes. at room temperature. Ethyl 6-bromo-3-hydroxy-5-methylpyrazine-2-carboxylate (6 g, 22.9 mmol, 1 eq.) was added in one portion and the resulting mixture was heated to 100° C. and stirred for 1 h. the mixture was then cooled to room temperature, triethylamine (57 ml) was added to the reaction mixture. This crude material was dissolved in DCM and passed through a plug of silica gel (eluting with 5-10% EtOAc-heptane). This solid was further purified by column chromatography to give ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (5.20 g, 18.6 mmol, 81.2%) as an orange solid. ¹ H NMR (500 MHz, chloroform-d) δ 4.48 (q, J=5.0, 10.0 Hz, 2H), 2.72 (s, 3H), 1.43 (t, J=7 .5 Hz, 3H). LC-MS (ESI): calc. for C ₈ H9BrClN ₂ O ₂ [M+H] mass/charge 278.9, found value 278.9.

Stage 4. Synthesis of HCl bis-salt (3S,4S)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-amine.

To a stirred solution of tert-butyl-(3S,4S)-4-(((R)-tert-butylsulfinyl)amino)-3-methyl-2oxa-8-azaspiro[4.5]decan-8-carboxylate (1520 mg, 4 05 mmol, 1 eq.) in anhydrous MeOH (20 ml) was added HCl (4 M in 1,4-dioxane, 10.1 ml, 40.4 mmol, 10 eq.) at room temperature. This solution was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure and the resulting material was dried under high vacuum (~1 Torr) for 5 h to give the HCl bis salt (3S,4S)-3-methyl-2-oxa-8-azaspiro[4.5] decane-4-amine (estimated quantitative yield), which was used without further purification. 1H NMR

- 177 041617 (500 MHz, MeOH-d ₄ ) δ 4.29 (qd, J=6.5, 4.1 Hz, 1H), 3.95 (d, J=9.4 Hz, 1H), 3 .83-3.78 (m, 1H), 3.56 (d, J=4.1

Hz, 1H), 3.48-3.42 (m, 1H), 3.41-3.36 (m, 1H), 3.17-3.04 (m, 2H), 2.08 (tt, J=11.9, 3.8 Hz, 2H), 2.03-1.97 (m,

1H), 1.87-1.81 (m, 1H), 1.32 (d, J=6.6 Hz, 3H).

Step 5. Synthesis of ethyl 3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-bromo-5methylpyrazine-2-carboxylate.

To a solution of ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (2.82 g, 10.1 mmol, 1 eq.) and byssalt HCl (3S,4S)-3-methyl-2-oxa -8-azaspiro[4.5]decan-4-amine (2.7 g, 11.2 mmol, 1.1 eq.) in DMA (50.4 ml) DIPEA (8.85 ml, 50.9 mmol, 5 equiv.). The reaction mixture was stirred and heated at 55°C overnight. The reaction mixture was then cooled and diluted with ethyl acetate (100 ml) and this organic phase was washed with 10% aqueous ammonium hydroxide solution (2x100 ml) and then with saturated aqueous sodium chloride solution (2x50 ml). The aqueous ammonium hydroxide layer was extracted with ethyl acetate (2x50 ml). The combined organic phases were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give ethyl 3((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl )-6-bromo-5-methylpyrazine-2-carboxylate as crude material which was used without further purification. LC-MS (ESI): calc. for C ₁₇ H ₂₆ BrN ₄ O ₃ [M+H] mass/charge: 413.1, found value 412.8.

Stage 6. Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-bromo-5methylpyrazin-2-yl)methanol .

To a solution of crude ethyl 3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6bromo-5-methylpyrazin-2-carboxylate (4 .17 g, 10.0 mmol, 1 eq.) in DCM (100 ml) at -78°C was added DIBAL-H (1 M in DCM, 40.0 ml, 40.0 mmol, 4 eq.) . The solution was then stirred at -78°C for 30 minutes. The solution was placed in an ice bath and allowed to heat for 20 minutes to completely reduce the aldehyde intermediate before cooling it back to -78°C. The resulting mixture was poured into a saturated aqueous solution of Rochelle's salt (250 ml), which had previously been cooled to 0°C. This solution was then allowed to warm to room temperature and stirred overnight. The layers were separated and the aqueous layer was extracted with DCM (3x50 ml). The combined organic layers were dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The crude material was purified by normal phase chromatography (0% to 20% MeOH (v/v) in DCM) to give (3-((3S,4S)-4-amino-3-methyl-2-oxa -8azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2-yl)methanol as a yellow solid (1.515 g, 4.07 mmol, 41% yield over two steps). 1H NMR (500 MHz, MeOH-d ₄ ) δ 4.59 (d, J=0.6 Hz, 2H), 4.22 (qd, J=6.4, 4.9 Hz, 1H), 3, 83 (d, J=8.7 Hz, 1H), 3.69 (d, J=8.6 Hz, 1H), 3.53-3.42 (m, 2H), 3.10 (ddd, J =13.3, 10.1, 3.1 Hz, 1H), 3.05-2.97 (m, 2H), 2.51 (s, 3H), 1.88 (dddd, J=29.7 , 13.9, 10.2, 3.8 Hz, 2H), 1.74-1.64 (m, 2H), 1.21 (d, J=6.5 Hz, 3H). LC-MS (ESI): calc. for calc. for C ₁₅ H ₂₄ BrN ₄ O ₂ [M+H] mass/charge: 371.11, found value 371.33.

Step 6. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-(2methyl-1, 3-benzoxazol-6-yl)pyrazin-2-yl} methanol.

(2-Methylbenzo[d]oxazol-6-yl)boronic acid (30.7mg, 174µmol), [1,1'bis(diphenylphosphino)ferrocene]dichloropalladium(11), complex with DCM (21.8mg, 26.8 µmol), potassium carbonate (73.9 mg, 536 µmol) and (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8- yl)-6-bromo-5methylpyrazin-2-yl)methanol (50 mg, 134 μmol) was weighed into a 2 dram vial. The reaction vessel was purged 3 times with N2. MeCN (1.34 mL, degassed with N2 sparging for 1 h) was added to counterbalance N2 and the headspace of the reaction vessel was purged 3 times with N2. The mixture was placed in a heating block preheated to 100° C. and stirred vigorously for 1.5 hours. The reaction mixture was cooled to room temperature and filtered through a celite pad. The filtrate was evaporated to dryness and purified by preparative HPLC to give 15.8 mg (19%) of the desired product. 1H NMR (500 MHz, MeOH-d ₄ ) δ 7.84 (dd, J=1.6, 0.6 Hz, 1H), 7.71 (dd, J=8.2, 0.6 Hz, 1H ), 7.62 (dd, J=8.2, 1.6 Hz, 1H), 4.75-4.70 (m, 2H), 4.31-4.23 (m, 1H), 3, 88 (d, J=8.6 Hz, 1H), 3.75 (d, J=8.6 Hz, 1H), 3.75 (d, J=8.6, 4.4 Hz, 2H), 3.20-3.13 (m, 1H), 3.13-3.03 (m, 2H), 2.70 (s, 4H), 2.53 (s, 3H), 2.02-1, 88 (m, 2H), 1.81-1.72 (m, 2H), 1.25 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₃ H ₂₈ ClN ₅ O ₃ : 424.24; the found value is 424.1.

The following example was synthesized by a method similar to the method in example 207.

- 178 041617

Table 5 Example 208

Example Structure Found M+1 EXAMPLE 208 OD/. 455.4

Example 209 Synthesis of {3-[(38.48)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-(1methyl-1 H -indol-2-yl)pyrazin-2-yl}methanol.

Me

B(OH) ₂

(3-((3 8.48)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-bromo-5methylpyrazin-2-yl)methanol was loaded into the vial (96 mg, 0.259 mmol, 1 eq.), (1-methyl-1H-indol-2-yl)boronic acid (68 mg, 0.388 mmol, 1.5 eq.), tetrakis(triphenylphosphine)palladium (60 mg, 0.0519 mmol, 0.2 eq.), potassium carbonate (107 mg, 0.776 mmol, 3 eq.) and a magnetic stirrer. Degassed ethanol (1.72 ml) was added, the vial was capped and the headspace was evacuated and filled with nitrogen three times. The vial was placed in an oil bath at 80° C. overnight. The reaction mixture was filtered through a Celite pad and the filtrate was concentrated. The crude product was purified by preparative HPLC to give (3-((38.48)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-5-methyl-6- (1-methyl-1Nindol-2-yl) pyrazin-2-yl) methanol (26 mg, 24%) as its formate salt. ^{1 H} NMR (500 MHz, MeOH d ₄ ) δ 8.57 (s, 1H), 7.60 (m, 1H), 7.45 (m, 1H), 7.25 (m 1H), 7.11 (m 1H), 6.62 (S, 1H), 4.73 (s, 2H), 4.38-4.18 (m, 1H), 3.94 (d, >8.8 Hz, 1H) , 3.82 (d, >8.8 Hz, 1H), 3.82 (d, >13.4 Hz, 1H), 1.76 (d, >12.4 Hz, 1H), 1.30 ( d, >6.5 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₄ H3iN ₅ O ₂ : 422.3; found value: 422.5.

The following examples were synthesized using a method similar to the method in example 209.

- 179041617

Table 6 Examples 210-227

Example Structure Found M+l EXAMPLE 210 X-N—| LQy. 409.5 EXAMPLE 211 X, Χ-Ν—, -1 410.3 EXAMPLE 212 J / v 2=( ⁰ I 458.5 EXAMPLE 213 F ΥίΤ 1h~1> 427.1 EXAMPLE 214 ·' · 487.4

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EXAMPLE 215 461.4 EXAMPLE 216 HO-L J Chu. 442.01 EXAMPLE 217 To 409.1 EXAMPLE 218 and t O 458.7 EXAMPLE 219 ^with| Ch-^ ⁿ J Chu 460.1 EXAMPLE 220 $ Ah 410.27 EXAMPLE 221 .7 ) ^—z 410.35

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EXAMPLE 222 CHK a "4 J Chu 424.2 EXAMPLE 223 fd ^ci Άά - ⁴ J 4+ - 459.34 EXAMPLE 224 XXli • 54- 483, 1 EXAMPLE 225 °' J NC 445.35 EXAMPLE 226 CQ4 J choo 447.4 EXAMPLE 227 Thu 1 °' 453.01

Example 228 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(2,3dichlorophenyl)-5-methylpyrazine -2-yl}methanol.

B(OH) _;

Me

Me

Vg

DIBALDCM

Me

Stage 1. Synthesis of ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate.

A mixture of 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (5.0 g, 17.8 mmol), (2,3dichlorophenyl)boronic acid (4.1 g, 21.3 mmol) and potassium carbonate ( 9.8 g, 71.2 mmol) in acetonitrile (178 ml) was degassed and Pd(dppf)Cl ₂ DCM (2.9 g, 3.56 mmol) was added. The reaction mixture was stirred at 100°C for 1 h, filtered and concentrated under reduced pressure. Purification by column chromatography provided ethyl 3-chloro-6-(2,3-dichlorophenyl)-5methylpyrazine-2-carboxylate (4.2 g, 12.1 mmol, 68.2%). LC-MS (ESI): calc. for C ₁₄ H ₁₁ Cl ₃ N ₂ O ₂ [M+H] mass/charge: 344.9, found value 345.1.

Step 2. Synthesis of ethyl 3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5- methylpyrazine-2-carboxylate.

To a solution of ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (1.2 g, 3.47 mmol) and HCl bis-salt (3S,4S)-3-methyl -2-oxa-8-azaspiro[4.5]decan-4-amine (0.92 g, 3.81 mmol) in DMA (17 ml) DIPEA (2.85 ml, 17.2 mmol) was added. The reaction mixture was heated to 55°C overnight. The reaction mixture was then cooled and diluted with ethyl acetate (100 ml) and this organic phase was washed with 182 041617 aqueous 182 041617 ammonium hydroxide solution (50 ml), dried over anhydrous magnesium sulfate, filtered and concentrated to give crude ethyl 3-((3S ,4S)-4-amino-3-methyl-2oxa-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (2.0 g) . The resulting material was used in the next step without further purification. LC-MS (ESI):

calc. for C ₂₃ H ₂₈ Cl ₂ N ₄ O ₃ [M+H] mass/charge: 479.1, found value 479.3.

Stage 3. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(2,3dichlorophenyl)-5-methylpyrazine -2-yl}methanol.

To a solution of ethyl 3-({3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin- 2-carboxylate (2 g, 4.2 mmol) in DCM (40 ml) DIBAL-H (1 M in DCM, 16.6 mmol) was added dropwise at -78°C. The solution was then stirred at -78°C for 30 minutes. The solution was placed in an ice bath and allowed to heat for 20 minutes to completely reduce the aldehyde intermediate before cooling back to -78°C. The solution was poured into a cold saturated aqueous solution of Rochelle's salt (100 ml). This solution was then allowed to warm to room temperature and stirred for an additional 3 hours. The layers were separated and the aqueous layer was extracted with DCM (2x40 ml). The combined organic layers were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. Purification by preparative HPLC provided {3-[(3S,4S)-4-amino-3-methyl-2oxa-8-azaspiro[4.5]decan-8-yl]-6-(2,3-dichlorophenyl)- 5-methylpyrazin-2-yl}methanol (0.83 g, 45.8%). 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.53 (s, 1H), 7.66 (dd, J=8.1, 1.6 Hz, 1H), 7.44 (t, J=7 .8 Hz, 1H), 7.37 (dd, J=7.7, 1.6 Hz, 1H), 4.70 (s, 2H), 4.32 (qd, J=6.5, 4, 2 Hz, 1H), 3.98 (d, J=9.0 Hz, 1H), 3.87 (d, J=9.0 Hz, 1H), 3.87 (d, J=4.2 Hz , 1H), 3.11 (dddd, J=35.0, 13.7, 11.1, 2.8 Hz, 2H), 2.28 (s, 3H), 2.06-1.95 (m , 3H), 1.94-1.87 (m, 1H), 1.76 (ddd, J=10.5, 4.6, 2.3 Hz, 1H), 1.33 (d, J=6 .5 Hz, 3H). LC-MS (ESI): calc. for C^C^Oi [M+H] mass/charge: 437.1, found value 437.36.

The following examples were synthesized using a method similar to the method in example 228.

________________Table 7. Examples 229-231________________

Example Structure Found M+1 EXAMPLE 229 So sow 437.4 EXAMPLE 230 -¾ ^С| WITH 453.35 EXAMPLE 231 s y □ 438.32

Example 232 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-(3methyl-2H- indazol-6-yl)pyrazin-2-yl}methanol.

ην'% !^ ⁿ 2

mind me oh me br. Λ BiyJk Ν 1. DIPEA, DMA ] [ nCC. ---- ^N ν ] ^Cl 2. Weight ₂ O J O^OEt O^i νΛΙΊ 1.Pd[P(Ph) ₃ ] ₄ νΛΑ ------------► η I EtOH ^Γ 2 .TFA, DCM Me Br< Λ Ί Ν I DIBAL-H I |l nhsoo ---------- !^ ^HBos * CyC' ^M ' ⁼ °θ ^Μ Me (Λ %h.....

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Stage 1. Synthesis of ethyl 6-bromo-3-((3S,4S)-4-((tert-butoxycarbonyl)amino)-3-methyl-2-oxa-8azaspiro[4.5]decan-8-yl)-5 -methylpyrazine-2-carboxylate.

A 200 ml vial was charged with ethyl 6-bromo-3-chloro-5-methylpyrazine-2-carboxylate (2.5 g, 8.94 mmol, 1 eq) and (3S,4S)-3-methyl-2 dihydrochloride -oxa-8-azaspiro[4.5]decan-4-amine (2.60 g, 10.7 mmol, 1.2 eq) and the vial was purged with nitrogen. DMA (89.3 ml) was then added to the vial followed by DIPEA (9.32 ml, 53.6 mmol, 6 eq.). The resulting orange solution was then heated to 85°C. After stirring for 23 h, the reaction mixture was cooled to room temperature, Boc ₂ O (7.76 g, 35.6 mmol, 4 eq.) was added to the reaction solution, and the resulting orange solution was allowed to stir at 23° C. for 1 h, it was diluted with EtOAc (200 ml) and water (50 ml). The layers were separated and the organic phase was washed with water (2x50 ml) and brine (50 ml). The washed organic phase was then dried over sodium sulfate, filtered and concentrated under reduced pressure to a yellow residue. The crude residue was purified by column chromatography to give ethyl 6-bromo-3-((3S,4S)-4-((tert-butoxycarbonyl)amino)-3-methyl-2-oxa-8azaspiro[4.5]decane-8 -yl)-5-methylpyrazine-2-carboxylate as a bright yellow solid (2.67 g, 58% yield). LC-MS (ESI): mass/charge: [M+Na] calc. for C ₂₂ H ₃₃ BrN ₄ O ₅ : 535.1; the found value is 535.3.

Stage 2. Synthesis of tert-butyl-((3S,4S)-8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl2-oxa-8-azaspiro[4.5]decane -4-yl) carbamate.

Ethyl 6-bromo-3-((3S,4S)-4-((tert-butoxycarbonyl)amino)-3methyl-2-oxa-8-azaspiro[4.5]decan-8-yl) was loaded into a dry 100 ml vial -5-methylpyrazine-2-carboxylate (1.15 g, 2.23 mmol, 1 eq.) and DCM (22.3 ml). The resulting yellow solution was cooled to -78°C before adding dropwise DIBAL-H (11.5 ml, 11.15 mmol, 5 eq.). After stirring for 1 h, the reaction mixture was heated to -40°C. After 1 hour, the reaction mixture was cooled to -78°C and quenched by adding a saturated aqueous solution of Rochelle's salt (20 ml) and providing heating of the resulting mixture to 23°C. The biphasic mixture was filtered through a Celite pad and transferred to a separating funnel. The layers were separated and the aqueous phase was extracted with DCM (2x20 ml). The combined organic extracts were then dried over sodium sulfate. The dried solution was filtered and the filtrate was concentrated under reduced pressure. The crude residue thus obtained was purified by column chromatography to give as tert-butyl-((3S,4S)-8-(5bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2- oxa-8-azaspiro[4.5]decan-4-yl)carbamate (466 mg, 44% yield) and tert-butyl-((3S,4S)-8-(5-bromo-3-formyl-6- methylpyrazin-2-yl)-3-methyl-2-oxa-8azaspiro[4.5]decan-4-yl)carbamate (253 mg, 24% yield). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₃₁ BrN ₄ O ₄ : 471.2; the found value is 471.1.

Step 3. Synthesis of tert-butyl-((3S,4S)-8-(3-(hydroxymethyl)-6-methyl-5-(3-methyl-1H-indazol-6yl)pyrazin-2-yl)-3- methyl 2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate.

The flask was loaded with tert-butyl-((3S,4S)-8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3methyl-2-oxa-8-azaspiro[4.5]decan- 4-yl)carbamate (88 mg, 0.187 mmol, 1 eq.), (3-methyl-1H-indazol-6yl)boronic acid (49 mg, 0.280 mmol, 1.5 eq.), tetrakis(triphenylphosphine)palladium ( 43.1 mg, 0.0373 mmol, 0.2 eq.), potassium carbonate (77 mg, 0.560 mmol, 3 eq.) and a magnetic stirrer. Degassed ethanol (1.24 ml) was added, the vial was capped and the headspace was evacuated and filled with nitrogen three times. The vial was placed in an oil bath at 80°C overnight. The reaction mixture was diluted with ethyl acetate, filtered through a Celite pad, and the filtrate was concentrated under reduced pressure. Purification by column chromatography provided tert-butyl((3S,4S)-8-(3-(hydroxymethyl)-6-methyl-5-(3-methyl-1H-indazol-6-yl)pyrazin-2- yl)-3-methyl-2-oxa-8azaspiro[4.5]decan-4-yl)carbamate (65 mg, 66%). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₈ H ₃₈ N ₆ O ₄ : 523.3; the found value is 523.2.

Stage 4. Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-5-methyl-6-(3methyl-1Н- indazol-6-yl)pyrazin-2-yl)methanol.

To a solution of tert-butyl-((3S,4S)-8-(3-(hydroxymethyl)-6-methyl-5-(3-methyl-1H-indazol-6-yl)pyrazin2-yl)-3-methyl- 2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate (65 mg, 0.124 mmol, 1 eq.) in DCM (3 ml) TFA (500 μl) was added. The resulting solution was allowed to stir for one hour at room temperature and concentrated under reduced pressure. The crude product was purified by preparative HPLC to give (3-((3S,4S)-4-amino-3-methyl-2-oxa-8azaspiro[4.5]decan-8-yl)-5-methyl-6-(3 -methyl-1H-indazol-6-yl)pyrazin-2-yl) methanol (31.6 mg, 60%). 1H NMR (500 MHz, MeOH-d ₄ ) δ 7.82 (dd, J=8.3, 0.8 Hz, 1H), 7.66 (t, J=1.1 Hz, 1H), 7, 37 (dd, J=8.3, 1.4 Hz, 1H), 4.74 (s, 2H), 4.32 (m, 1H), 3.99 (d, J=9.1 Hz, 1H ), 3.88 (d, J=9.1 Hz, 1H), 3.88 (d, J=4.2 Hz, 1H), 3.08 (m, 2H), 2.62 (s, 3H ), 2.53 (s, 3H), 2.08-1.97 (m, 2H), 1.93 (d, J=13.2 Hz, 1H), 1.77 (d, J=13, 2 Hz, 1H), 1.77 (d, J=6.5 Hz, 3H). lC-MS (ESI): mass/charge: [M+H] calc. for C ₂₃ H ₃₀ N ₆ O ₂ : 423.2; the found value is 423.1.

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Example 233 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(7-chloro-2Nindazol-6- yl)-5-methylpyrazin-2-yl}methanol.

During the synthesis of {3-[(3 S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(7-chloro-2Н-indazol6-yl )-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 232, except that (3-methyl-1H-indazol-6-yl)boronic acid was replaced by 7-chloro-6( 4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indazole, in the form of its formate salt. 1H NMR (500

MHz, MeOH-d4) δ 8.54 (s, 1H), 8.22 (s, 1H), 7.85 (d, J=8.2 Hz, 1H), 7.19 (d, J=8 .2 Hz, 1H), 7.19 (d, J=8.9 Hz, 1H), 3.86 (d, J=8.9 Hz, 1H), 3.86 (d, J=6.5 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂ 2H27C1N ₆ O ₂ : 443.1; the found value is 443.1.

Synthesis of 7-chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indazole.

Stage 1. Synthesis of 6-bromo-7-chloro-1H-indazole.

Pure hydrazine (4.8 ml) was added to a solution of 4-bromo-3-chloro-2-fluorobenzaldehyde (1.15 g, 4.84 mmol, 1 eq.) in THF (4.8 ml). The resulting biphasic mixture was vigorously stirred for 16 hours at 90°C. The cooled reaction mixture was added dropwise to a stirred solution of water (25 ml) to give a precipitate as a solid. The white solid was collected by filtration, washed with water and dried under vacuum to constant weight to give 6-bromo7-chloro-1H-indazole (1.0 g, 89%) and used without further purification. LC-MS (ESI): mass/charge: [M+H] calc. for C ₇ H ₄ BrClN ₂ : 230.9; found value: 230.6.

Stage 2. Synthesis of 7-chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indazole.

To a vial containing 6-bromo-7-chloro-1H-indazole (346 mg, 1.49 mmol, 1 eq.), bis(pinacolato)diboron (566 mg, 1.5 eq.), Pd(dppf)Cl ₂ -DCM (60.8 mg, 0.0745 mmol, 0.05 eq.), potassium acetate (438 mg, 4.47 mmol, 3 eq.) and a magnetic stirrer, degassed dioxane (14.9 ml) was added. The vial was sealed and the headspace was evacuated and filled with nitrogen three times. The vial was heated in the reaction block at 120° C. for 16 hours. The cooled reaction mixture was diluted with ethyl acetate and filtered through a Celite pad. The filtrate was concentrated under reduced pressure to give a crude product which was purified by column chromatography to give 7-chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H- indazole (186 mg, 45%) as a white solid. LC-MS (ESI): mass/charge: [M+H] calc. for C ₁₃ H ₁₆ BClN ₂ O ₂ : 279.1; found value: 279.1.

Example 234 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(5-chloro-2Nindazol-6- yl)-5-methylpyrazin-2-yl}methanol.

During the synthesis of {3-[(3 S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(5-chloro-2Н-indazol6-yl )-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 233, except that 6-bromo-7-chloro-1H-indazole was replaced by 6-bromo-5-chloro-1H- indazole, in the form of its formate salt. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.50 (s, 1H), 8.13 (d, J=1.0 Hz, 1H), 7.99 (d, J=1.0 Hz, 1H), 7.99 (d, J=9.1 Hz, 1H), 3.89 (d, J=9.1 Hz, 1H), 3.89 (d, J=12.5 Hz, 1H) , 1.78 (d, J=12.5 Hz, 1H), 1.78 (d, J=6.5 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂ 2H2 ₇ ClN6O ₂ : 443.1; the found value is 443.4.

The following examples were synthesized by a method similar to the method in example 232.

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Table 8 Examples 235-253

Example Structure Found M+1 EXAMPLE 235 CI 1 J Tsu 443, 1 EXAMPLE 236 CI 7 o> - 442.2 EXAMPLE 237 % Hmm>· 409.3 EXAMPLE 238 437.3 EXAMPLE 239 OOC JQ>. 437.1 EXAMPLE 240 X X ' ¹ Z 423.4 EXAMPLE 241 ¢0^ 424.5

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EXAMPLE 242 J Chu... 423.3 EXAMPLE 243 h ⁷ h 423.3 EXAMPLE 244 '<A/h - ⁴ J su. 421.4 EXAMPLE 245 h 0 / ^- z h 423.3 EXAMPLE 246 h 1 ' ^J Z X 410.2 EXAMPLE 247 h G 409.3

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EXAMPLE 248 442.5 EXAMPLE 249 7 409, 2 EXAMPLE 250 asu 438.2 EXAMPLE 251 with A / 434.4 EXAMPLE 252 jQi ^С| TT1| ^ci 437.1 EXAMPLE 253 su d tsu 423.13

Example 254 Synthesis of {3-[(1R)-1-amino-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-[(1-methyl-1H-indol-7yl)sulfanyl]pyrazine -2 -yl} methanol.

Stage 1. Synthesis of (R)-tert-butyl-(8-(3-(hydroxymethyl)-6-methyl-5-((1-methyl-1H-indol-7yl)thio)pyrazin-2 -yl)-8 -azaspiro[4.5]decan-1-yl)carbamate.

tert-Butyl-((3S,4S)-8-(5-bromo-3-(hydroxymethyl)6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[ 4.5]decan-4-yl)carbamate (30 mg, 65.8 µmol), 1-methyl1H-indol-7-thiol (22.4 mg, 131 µmol), Pd ₂ (dba) ₃ (6.02 mg, 6.58 µmol), Xantphos (7.57 mg, 13.1 µmol) and DIPEA (22.7 µl, 131 µmol). The vial was evacuated in a centralized vacuum system for 10 min. Then degassed 1,4-dioxane (658 μl) was added. The mixture was purged with N2 and evacuated three times. The reaction mixture was stirred under microwave conditions at 120° C. for 2 hours. The resulting reaction mixture was filtered and concentrated under reduced pressure. The residue was purified by column chromatography to give the desired product, which is (R)-tert-butyl-(8-(3-(hydroxymethyl)-6-methyl5-((1-methyl-1H-indol-7-yl)thio )pyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (30.0 mg, 55.7 µmol, 84.9%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₉ H ₃₉ N ₅ O ₃ S: 538.28; the found value is 538.5.

Stage 2. Synthesis of {3-[(1C)-1-amino-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-[(1-methyl-1H-indol-7yl)sulfanyl]pyrazine -2 -yl} methanol.

To a solution of (R)-tert-butyl-(8-(3 -(hydroxymethyl)-6-methyl-5-((1 -methyl-1 H-indol-7-yl)thio)pyrazin2-yl)-8- azaspiro[4.5]decan-1-yl)carbamate (30 mg, 55.7 µmol) in MeOH (2 ml) was added 4 M HCl in dioxane (1 ml, 4.00 mmol). The mixture was stirred in a closed vial for 3 hours. The resulting reaction mixture was concentrated under reduced pressure. The residue was purified by preparative HPLC to give the desired product, which is {3-[(1R)-1-amino-8-188 041617 azaspiro[4.5]decan-8-yl]-5-methyl-6-[(1- methyl-1H-indol-7-yl)sulfanyl]pyrazin-2-yl}methanol (19.0 mg,

43.4 µmol, 78.1%), as its salt with formic acid. 1H NMR (500 MHz, MeOH-d ₄ ) 88.55 (s, 2H, formic acid), 7.65 (dd, J=7.9, 1.1 Hz, 1H), 7.24 (dd, J =7.4, 1.2 Hz, 1H), 7.12 (d, J=3.2 Hz, 1H), 7.066.97 (m, 1H), 6.51 (d, J=3.2 Hz , 1H), 7.06-6.97 (m, 1H), 6.51 (d, J=14.3 Hz, 2H). LC-MS (ESI) mass/charge:

[M+N] calc. for C ₂₄ H ₃₁ N ₅ OS: 438.22; the found value is 438.47.

Example 255 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-{[2(trifluoromethyl) pyridin-3-yl]sulfanyl}pyrazin-2-yl}methanol.

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-5-methyl-6-{[2(trifluoromethyl)pyridine-3 -yl]sulfanyl}pyrazin-2-yl}methanol was synthesized by a method similar to the method in example 254, except that t-butyl-(R)-(8-(5-bromo-3(hydroxymethyl)-6- methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate was replaced by tert-butyl((3S,4S)-8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin- 2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4yl)carbamate and 1-methyl-1H-indol-7-thiol were replaced by 2-(trifluoromethyl)pyridine-3-thiol. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.60-8.48 (m, 2H), 7.76 (dd, J=8.3, 1.3 Hz, 1H, formic acid), 7, 52 (dd, J=8.1, 4.6 Hz, 1H), 4.58 (s, 2H), 4.34-4.21 (m, 1H), 3.92-3.63 (m, 5H), 3.11 (m, 2H), 2.50 (s, 3H), 2.10-1.63 (m, 4H), 1.29 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₆ F ₃ N ₅ O ₂ S: 470.18; the found value is 470.4.

The following examples were synthesized using a method similar to the method in example 254.

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Table 9 Examples 256-272

Example Structure Found M+1 EXAMPLE 256 Oh and 465.2 EXAMPLE 257 g y / ^- _ ¹ t/ and 445.15 EXAMPLE 258 ο.— 465.1 EXAMPLE 259 w. T HCHO 461.1 EXAMPLE 260 O I - 470.1 EXAMPLE 261 o and =4^ 484.1

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EXAMPLE 262 ΌΤ Oh --\ at And 463, 1 EXAMPLE 263 / 484.1 EXAMPLE 264 aU ^y U Mq he 451 EXAMPLE 265 usu He 451.2 EXAMPLE 266 ^0 O I 'to to 469, 1 EXAMPLE 267 >-r 437.15

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Example 273 Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-((3-chloro-2(( tetrahydro-2H-pyran-4-yl)amino)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol.

Me ^HN V% ^ON^I>'' ^Me

L, o

Stage 1. Synthesis of 2-ethylhexyl-3-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino)pyridin-4yl)thio)propanoate.

Tetrahydro-2H-pyran-4-amine (173 mg, 1.72 mmol) and DIPEA (497 µl, 2.86 mmol). The reaction mixture was stirred under microwave conditions at 140° C. for 6 hours. The resulting reaction mixture was concentrated under reduced pressure, and the residue was purified by column chromatography to obtain the desired product, which is 2-ethylhexyl-3-((3- chloro-2-((tetrahydro-2H-pyran-4-yl)amino)pyridin-4yl)thio)propanoate (95.0 mg, 221 µmol, 38.6%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₃₃ ClN ₂ O ₃ S: 429.19; the found value is 429.2.

Stage 2. Synthesis of 2-ethylhexyl-3-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)propanoate.

To a suspension of 2-ethylhexyl-3-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino)pyridin-4yl)thio)propanoate (92 mg, 214 µmol) in MeOH (2.14 ml) sodium methoxide (23.1 mg, 428

- 192 041617 µmol). The reaction mixture was stirred in a closed vial at room temperature for 30 min. The resulting reaction mixture was concentrated in vacuo and the residue was purified by column chromatography using 0-20% MeOH/DCM to give the desired product, which is 3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino )pyridine-4-thiol (27.0 mg, 110 µmol, 51.6%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₀ H ₁₃ ClN ₂ OS: 245.04; the found value is 245.0.

Stage 3. Tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino)pyridin-4yl)thio)-3- (hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate.

tert-Butyl-((3S,4S)-8-(5-bromo-3-(hydroxymethyl)6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[ 4.5]decan-4-yl)carbamate (45 mg, 95.4 µmol), 3-chloro-2((tetrahydro-2H-pyran-4-yl)amino)pyridine-4-thiol (26.7 mg, 104 µmol), Pd ₂ (dba) ₃ (8.73 mg, 9.54 µmol), Xantphos (11.0 mg, 19.0 µmol) and DIPEA (33.0 µl, 190 µmol). The vial was evacuated in a centralized vacuum system for 10 min, then degassed 1,4-dioxane (954 μl) was added. The reaction mixture was purged with N ₂ and evacuated three times and then stirred at 120° C. under microwave conditions for 1.5 hours. The resulting reaction mixture was filtered and the filtrate was concentrated in vacuo. The residue was purified by column chromatography to give the desired product, which is t-butyl((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino) pyridin-4-yl)thio)-3-(hydroxymethyl)-6methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate (36.0 mg, 56 .6 µmol, 59.5%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₃₀ H ₄₃ ClN ₆ O ₅ 3: 635.27; the found value is 635.4.

Stage 4. Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-((3-chloro-2(( tetrahydro-2H-pyran-4-yl)amino)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol.

To a solution of tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)amino)pyridin-4yl)thio)-3-( hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate (35 mg, 55.0 µmol) in MeOH (1 ml) was added 4 M hydrogen chloride in dioxane (196 μl, 785 μmol).

The reaction mixture was stirred at 50°C for 30 min. The resulting reaction mixture was concentrated in vacuo. The residue was purified by preparative HPLC to give (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-((3-chloro -2-((tetrahydro-2H-pyran-4yl)amino)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol (15.0 mg, 28.0 µmol, 51.0%) in form of its salt with formic acid. ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H), (formic acid), 7.68 (d, J=5.5 Hz, 1H), 5.86 (d, J =5.5 Hz, 1H), 5.86 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₃₀ H ₄₂ ClN ₅ O ₆ S: 535.22; the found value is 535.4.

Example 274 {3-[(1R)-1-Amino-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(methylamino)pyridin-4yl]sulfanyl}-5- methylpyrazin-2-yl}methanol.

Me

{3-[(1R)-1-Amino-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(methylamino)pyridin-4-yl]sulfanyl}5-methylpyrazin- 2-yl}methanol was synthesized by a method similar to that of Example 273, except that tetrahydro-2H-pyran-4-amine and t-butyl-((3S,4S)-8-(5-bromo-3- (hydroxymethyl)6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate were replaced by methanamine and tert-butyl-(R)-(8-( 5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate, respectively. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.54 (s, 1H, formic acid), 7.68 (d, J=5.6 Hz, 1H), 5.84 (d, J=5, 6 Hz, 1H), 4.65 (s, 2H), 3.92 (m, 3H), 3.29-3.13 (m, 4H), 2.97 (s, 3H), 2.50 ( s, 3H), 1.97-1.68 (m, 6H), 1.58 (t, J=13.1 Hz, 2H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₉ ClN ₆ OS: 449.18; the found value is 449.35.

Example 275 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-({3-chloro-2[(oxetane -3-yl)amino]pyridin-4-yl}sulfanyl)-5-methylpyrazin-2-yl}methanol. Me

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-({3-chloro-2-[(oxetan-3yl )amino]pyridin-4-yl}sulfanyl)-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 273, except that tetrahydro-2H-pyran-4-amine was replaced by oxetan- 3-amine. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.53 (s, 4H, formic acid), 7.79 (d, J=7.0 Hz, 1H), 6.25 (d, J=7, 0 Hz, 1H), 6.25 (d, J=10.6, 6.5, 3.3 Hz, 1H), 4.34-4.23 (m, 1H), 4.01-3.67 (m, 6H), 3.31-3.13

- 193 041617 (m, 2H), 2.51 (s, 3H), 2.02-1.65 (m, 4H), 1.30 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. For

C ₂₃ H ₃₁ ClN ₆ O ₃ S: 507.19; the found value is 507.5.

The following example was synthesized by a method similar to the method in example 273.

Table 10 Example 276

Example 277 Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-((3-chloro-2(( tetrahydro-2H-pyran-4-yl)oxy)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol.

Stage 1. Synthesis of 4-bromo-3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridine.

Tetrahydro-2H-pyran-4-ol (194 mg, 1.90 mmol) and cesium carbonate (772 mg, 2.37 mmol). The reaction mixture was stirred in a closed vial at 100°C for 90 min. The resulting reaction mixture was diluted with EtOAc and H ₂ O. The aqueous layer was extracted two more times with EtOAc. The combined organic layers were dried over MgSO ₄ , filtered and concentrated in vacuo. The residue was purified by column chromatography to give the desired product, which is 4-bromo-3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridine (91.0 mg, 344 µmol, 36.2 %). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₀ H11BrClNO ₂ : 291.97; the found value is 291.7.

Stage 2. Synthesis of 2-ethylhexyl-3-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)propanoate.

2-Ethylhexyl-3 -mercaptopropanoate (130 mg, 589 µmol), Pd ₂ (dba) ₃ (29.3 mg, 32.1 µmol), Xantphos (31.0 mg, 53.6 µmol) and DIPEA (185 µl, 1.07 mmol ). The reaction mixture was stirred at 110° C. under N ₂ for 5 hours. The resulting reaction mixture was diluted with H ₂ O and DCM. The organic layer was separated, dried over MgSO ₄ , filtered and concentrated in vacuo. The residue was purified by column chromatography using 033% EtOAc/heptane to give the desired product, which is 2-ethylhexyl-3-((3chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4- yl)thio)propanoate (224 mg, 520 µmol, 97.3%). LCMS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₃₂ ClNO ₄ S: 430.17; the found value is 430.4.

Stage 3. Synthesis of 3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridine-4-thiol.

To a suspension of 2-ethylhexyl-3-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)propanoate (224 mg, 520 µmol) in MeOH (5.19 ml) sodium methoxide (55.6 mg, 1.03 mmol) was added. The reaction mixture was stirred in a closed vial at room temperature for 30 min. The resulting reaction mixture was concentrated in vacuo and the residue was purified using column chromatography to obtain the desired product, which is 3chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridine-4-thiol (95.0 mg , 386 µmol, 74.8%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₀ H ₁₂ ClNO ₂ S: 246.03; the found value is 246.0.

- 194 041617

Step 4. Synthesis of tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)-3 -(hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate.

tert-Butyl-((3S,4S)-8-(5-bromo-3-(hydroxymethyl)6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[ 4.5]decan-4-yl)carbamate (45 mg, 95.4 µmol), 3-chloro-2((tetrahydro-2H-pyran-4-yl)oxy)pyridine-4-thiol (26.8 mg, 104 µmol), Pd ₂ (dba) ₃ (8.73 mg, 9.54 µmol), Xantphos (11.0 mg, 19.0 µmol) and DIPEA (33.0 µl, 190 µmol). The vial was evacuated in a centralized vacuum system for 10 min, then 1,4-dioxane (954 μl) was added. The mixture was purged with N2 and evacuated three times and then stirred at 120° C. for 1.5 hours under microwave conditions. The resulting reaction mixture was filtered through a Celite pad and the filtrate was concentrated in vacuo. The residue was purified by column chromatography using 0-100% EtOAc/heptanes. Pure fractions were combined and concentrated in vacuo to give the desired product, which is tert-butyl-((3S,4S)-8-(5-((3-chloro2-((tetrahydro-2H-pyran-4-yl)oxy) pyridin-4-yl)thio)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate (55.0 mg, 86 .4 µmol, 90.7%). LC-MS (ESI): mass/charge: [M+H] calc. for C ₃₀ H ₄₂ ClN ₅ O ₆ S: 636.25; the found value is 636.5.

Step 5. Synthesis of (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-((3-chloro-2(( tetrahydro-2H-pyran-4-yl)oxy)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol.

To a solution of tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)-3-( hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate (50 mg, 78.5 µmol) in MeOH (1 ml) was added hydrogen chloride in dioxane (196 µl, 785 µmol). The reaction mixture was stirred at 50°C for 30 min. The resulting reaction mixture was concentrated in vacuo. The residue was purified by reverse phase HPLC to give the desired product, which is (3-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8yl)-6- ((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4-yl)thio)-5-methylpyrazin-2-yl)methanol (17.0 mg, 31.7 µmol , 40.4%) in the form of its salt with formic acid. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H, formic acid), 7.68 (d, J=5.5 Hz, 1H), 5.86 (d, J=5, 5 Hz, 1H), 5.86 (d, J=6.5 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₅ H ₃ 4ClN ₅ O ₄ S: 536.20; the found value is 536.4.

Example 278 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[(3-chloro-2methoxypyridin-4- yl)sulfanyl]-5-methylpyrazin-2-yl}methanol.

Me

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[(3-chloro-2-methoxypyridin-4yl)sulfanyl ]-5-Methylpyrazin-2-yl}methanol was synthesized by a method similar to that of Example 277, except that tetrahydro-2H-pyran-4-ol was replaced with MeOH. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.56 (s, 1H, formic acid), 7.80 (d, J=5.5 Hz, 1H), 6.25 (d, J=5, 5 Hz, 1H), 4.65 (s, 2H), 4.28 (m, 1H), 4.00 (s, 3H), 3.85 (m, 3H), 3.40-3.14 ( m, 4H), 2.49 (s, 3H), 2.04-1.67 (m, 4H), 1.27 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₃ S: 466.16; the found value is 466.37.

Example 279 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(oxetane3 -yloxy)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

Me

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(oxetan-3yloxy) pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 277, except that tetrahydro-2H-pyran-4-ol was replaced by oxetan-3-ol . 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.46 (s, 4H, formic acid), 8.18 (d, J=7.0 Hz, 1H), 6.83 (d, J=6, 9 Hz, 1H), 5.69-5.48 (m, 1H), 5.05-4.77 (m, 4H), 4.67 (s, 2H), 4.31 (dd, J=6, 6, 4.3 Hz, 1H), 4.17-3.83 (m, 5H), 3.45-3.34 (m, 2H), 3.29-3.12 (m, 1H), 2 .52 (s, 2H), 2.01-1.72 (m, 4H), 1.33 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₃ S: 508.17; the found value is 508.4.

- 195 041617

Example 280.

1-(4-((5-((3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6(hydroxymethyl)-3-methylpyrazin- 2-yl)thio)-3-chloropyridin-2-yl)azetidine-3-carbonitrile.

Pd2(dba)3. (1 mol.%). xantphos. (2 mol.%)

DIPEA. dioxane 120°C. 1.5 hours

Stage 1. Synthesis of octan-3-yl-3-((3-chloro-2-(3-cyanoazetidin-1-yl)pyridin-4-yl)thio)propanoate.

3-azetidinecarbonitrile hydrochloride (152 mg, 1.29 mmol) and DIPEA ( 298 µl, 1.72 mmol). The reaction mixture was stirred in a closed vial at 60° C. for 6 h. The resulting reaction mixture was concentrated in vacuo and the residue, octan-3-yl-3-((3-chloro-2-(3-cyanoazetidin-1-yl )pyridin-4yl)thio)propanoate was carried to the next step without any further purification and assuming a quantitative yield. LC-MS (ESI) mass/charge: [M+H] calc. for C2oH ₂₈ ClN ₃ O ₂ S: 410.17; the found value is 409.9.

Stage 2. Synthesis of 1-(3-chloro-4-mercaptopyridin-2-yl)azetidine-3-carbonitrile.

To a suspension of octan-3-yl-3-((3-chloro-2-(3-cyanoazetidin-1-yl)pyridin-4-yl)thio)propanoate (176 mg, 429 µmol) in MeOH (4.28 ml ) sodium methoxide (44.7 mg, 828 µmol) was added. The mixture was stirred at room temperature for 30 minutes. The resulting reaction mixture was concentrated in vacuo and the residue was purified by column chromatography to give the desired product, which is 1-(3-chloro-4-mercaptopyridin-2-yl)azetidine-3-carbonitrile (89.0 mg, 394 µmol , 91.9%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₉ H ₈ ClN ₃ S: 226.01; the found value is 225.7.

Step 3. Synthesis of 1-(4-((5-((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6(hydroxymethyl)- 3-methylpyrazin-2-yl)thio)-3-chloropyridin-2-yl)azetidine-3-carbonitrile.

1-(3-Chloro-4-mercaptopyridin-2-yl)azetidine-3-carbonitrile (81.9mg, 363µmol), (3-((3S,4S)-4amino-3-methyl-2-oxa- 8-azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2-yl)methanol (90 mg, 242 µmol), Xantphos (28.0 mg, 48.4 µmol) and Pd ₂ ( dba) ₃ (22.1 mg, 24.2 µmol) was weighed into a microwave vial. The reaction vessel was purged 3 times with N2 and dioxane (degassed) (2.42 ml) was added followed by DIPEA (84.0 μl, 484 μmol). The headspace of the reaction vessel was purged 3 more times with N ₂ and the mixture was heated to 120° C. under microwave irradiation for 2 h. HPLC to give the desired product, which is 1-(4-((5((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6- (hydroxymethyl)-3-methylpyrazin-2yl)thio)-3-chloropyridin-2-yl)azetidine-3-carbonitrile (32.0 mg, 62 μmol, 25.8%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₄ H ₃₀ ClN ₇ O ₂ S: 516.20; the found value is 516.1. 1H NMR (500 MHz, MeOHd4) δ 8.38 (s, 1H), 7.79 (d, J=5.4 Hz, 1H), 6.09 (d, J=5.4 Hz, 1H), 6.09 (d, J=8.6 Hz, 2H), 4.40-4.35 (m, 3H), 4.35-4.29 (m, 1H), 4.02-3.85 ( m, 3H), 3.72 (tt, J=8.7, 6.0 Hz, 1H), 3.47 (d, J=4.1 Hz, 1H), 3.22-3.15 (m , 1H), 3.12 (ddd, J=13.7, 11.2, 2.7 Hz, 1H), 2.50 (s, 3H), 2.03-1.94 (m, 2H), 1.91 (d, J=13.5 Hz, 1H), 1.78-1.71 (m, 1H), 1.34 (d, J=6.5 Hz, 3H).

Example 281 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(1nimidazole -1-yl)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol. Me

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(1H-imidazol- 1yl)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to that of Example 280, except that 3-azetidinecarbonitrile was replaced with imidazole. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.53 (s, 1H, formic acid), 8.29-8.09 (m, 2H), 7.67 (t, J=1.4 Hz, 1H), 7.18 (dd, J=1.5, 1.0 Hz, 1H), 6.81 (d, J=5.4 Hz, 1H), 4.67 (s, 2H), 4, 36-4.24(m, 1H), 4.00-3.78(m,

- 196 041617

4H), 3.28-3.11 (m, 3H), 2.55 (s, 3H), 2.02-1.83 (m, 4H), 1.31 (d, J=6.5 Hz , 3H). LC-MS (ESI) mass/charge:

[M+N] calc. for C ₂₁ H ₂₈ ClN ₅ O ₃ S: 502.17; the found value is 502.3.

Example 282 6-[4-({5-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azαspiro[4.5]decαn-8-yl]-6(hydroxymethyl)-3 -methylpyrazin-2-yl}sulfanyl)-3-chloropyridin-2-yl]-1λ ⁶ -tiα-6-azαspir[3.3]heptane1,1-dione.

Me

6-[4-({5-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(hydroxymethyl)-3methylpyrazin-2 -yl}sulfanyl)-3-chloropyridin-2-yl]-1λ ⁶ -thia-6-azaspiro[3.3]heptan-1,1-dione was synthesized by a method similar to that of Example 280, except that 3-azetidinecarbonitrile was replaced by 1-thia-6-azaspiro[3.3]heptan-6-ium-1,1-dioxide. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.53 (s, 1H, formic acid), 7.79 (d, J=5.4 Hz, 1H), 6.09 (d, J=5, 4 Hz, 1H), 6.09 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₅ H ₃₃ ClN ₆ O ₄ S ₂ : 581.17; the found value is 581.4.

Example 283 Synthesis of 1-[4-({5-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azαspiro[4.5]decan-8-yl]-6(hydroxymethyl)- 3-methylpyrazin-2-yl}sulfanyl)-3-chloropyridin-2-yl]azetidin-3-ol. Me

HE

1-[4-({5-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(hydroxymethyl)-3methylpyrazin-2 -yl}sulfanyl)-3-chloropyridin-2-yl]azetidin-3-ol was synthesized by a method similar to the method in example 280, except that 3-azetidinecarbonitrile was replaced by 3hydroxyazetidine (HCl salt). ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H), 7.73 (d, J=5.5 Hz, 1H), 5.98 (d, J=5.4 Hz , 1H), 4.65 (s, 2H), 4.65-4.60 (m, 1H), 4.52-4.46 (m, 2H), 4.33-4.27 (m, 1H ), 4.02 (ddd, J=9.1, 4.7, 1.2 Hz, 2H), 3.95 (d, J=8.9 Hz, 1H), 3.91-3.79 ( m, 5H), 3.28 (d, J=4.5 Hz, 1H), 3.23 (ddd, J=13.8, 10.7, 3.0 Hz, 1H), 3.15 (ddd , J=13.5, 10.8, 2.8 Hz, 1H), 2.50 (s, 3H), 2.00-1.90 (m, 2H), 1.85 (d, J=13 .7 Hz, 1H), 1.74 (d, J=12.8 Hz, 1H), 1.30 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₃ H ₃₁ ClN ₆ O ₃ S: 507.20; the found value is 507.1.

Example 284 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-( 3methanesulfonylazetidin-1-yl)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

Me

SO2 _Me -1-yl)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 280, except that 3-azetidinecarbonitrile was replaced by 3-methylsulfonylazetidine (HCl salt). ¹ H NMR (500 MHz, MeOHd ₄ ) δ 8.55 (s, 1H), 7.79 (d, J=5.4 Hz, 1H), 6.07 (d, J=5.4 Hz, 1H ), 6.07 (d, J=9.0 Hz, 1H), 3.91-3.80 (m, 3H), 3.29 (d, J=4.4 Hz, 1H), 3.23 (ddd, J=13.6, 10.7, 3.1 Hz, 1H), 3.15 (ddd, J=13.6, 10.9, 2.9 Hz, 1H), 3.04 (s , 3H), 2.50 (s, 3H), 2.02-1.89 (m, 2H), 1.85 (d, J=13.4 Hz, 1H), 1.77-1.69 ( m, 1H), 1.30 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C24H33ClN6O4S2: 569.18; the found value is 569.1.

Example 285 {3-[(3S,4S)-4-Amino-3-methyl-2-oxα-8-azaspiro[4.5]decαn-8-ul]-6-({3-chloro-2-[( 1S,4S)2-oxa-5-azabicyclo[2.2.1]heptan-5-yl]pyridin-4-yl}sulfanyl)-5-methylpyrazin-2-yl}methanol.

Me

- 197 041617 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-({3-chloro-2-[( 1S,4S)-2-oxa-5azabicyclo[2.2.1]heptan-5-yl]pyridin-4-yl}sulfanyl)-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 280, for except that 3azetidinecarbonitrile was replaced by (1S,4S)-2-oxa-5-azabicyclo[2.2.1]heptane (HCl salt). 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.50 (s, 1H), 7.76 (d, J=5.4 Hz, 1H), 6.03 (d, J=5.3 Hz, 1H), 4.66 (s, 2H), 4.65-4.63 (m, 2H), 4.32 (qd, J=6.5, 4.2 Hz, 1H), 4.08 (dd , J=7.6, 0.8 Hz, 1H), 4.01-3.83 (m, 6H), 3.46-3.40 (m, 2H), 3.19 (ddd, J=13 .8, 11.0, 3.0 Hz, 1H), 3.12 (ddd, J=13.8, 11.2, 2.7 Hz, 1H), 2.51 (s, 3H), 2, 03-1.86 (m, 5H), 1.79-1.71 (m, 1H), 1.34 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C25H33ClN6O3S: 533.21; the found value is 533.3.

The following example was synthesized by a method similar to the method in example 280.

Table 11 Example 286

Example 287 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(methylamino )pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol. O

Me Me ^B YiT _N Pd2(dba)3. (1 mol.%).

__ Υ ⁺ JyY Xantphos. (2 mol, %) ^H %e “71^ ^HN 'Me o -o

Stage 1. Synthesis of 2-ethylhexyl-3-((3-chloro-2-(methylamino)pyridin-4-yl)thio)propanoate.

To a solution of 2-ethylhexyl-3-((3-chloro-2-fluoropyridin-4-yl)thio)propanoate (230 mg, 661 µmol) in THF (6.60 ml) was added a 2 M solution of methanamine (1 ml, 2 .00 mmol) in THF. The reaction mixture was stirred under microwave conditions at 140°C for 8 hours. The resulting reaction mixture was concentrated in vacuo and the residue was purified by column chromatography using 0-20% EtOAc/Hex to obtain the desired product, which is 2- ethylhexyl 3-((3-chloro-2-(methylamino)pyridin-4-yl)thio)propanoate (180 mg, 501 µmol, 75.9%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₇ H ₂₇ ClN ₂ O ₂ S: 359.15; the found value is 359.4. Stage 2. Synthesis of 3-chloro-2-(methylamino)pyridine-4-thiol.

Sodium methoxide (85.2 mg, 1.50 mmol). The reaction mixture was stirred in a sealed vial at room temperature for 30 min. The resulting mixture was concentrated under reduced pressure, and the residue was purified by column chromatography to give 3-chloro-2-(methylamino)pyridine-4-thiol (60.0 mg, 343 μmol, 68.7%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₆ H ₇ ClN ₂ S: 175.00; the found value is 174.9.

Stage 3. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(methylamino )pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

(3-((3S,4S)-4-amino-3-methyl-2-oxa-8azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2-yl ) methanol (50 mg, 134 µmol), 3-chloro-2(methylamino)pyridine-4-thiol (35.1 mg, 201 µmol), Pd ₂ (dba) ₃ (12.2 mg, 13.4 µmol) , Xantphos (15.5 mg, 26.8 µmol) and DIPEA (69.9 µl, 402 µmol). The mixture was evacuated in a centralized vacuum system for 10 minutes, then degassed 1,4-dioxane (1.34 ml) was added. The reaction mixture was degassed and stirred at 120° C. under microwave conditions for 2 hours. The resulting reaction mixture was filtered through a Celite pad, and the filtrate was concentrated under reduced pressure. The residue was purified by preparative HPLC to give the desired product, which is {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8

- 198 041617 azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(methylamino)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2yl}methanol (26.0 mg, 55 .9 µmol, 41.7%), as its salt with formic acid. 1H NMR (500 MHz,

MeOH-d ₄ ) δ 8.42 (s, 2H, formic acid), 7.68 (d, J=5.6 Hz, 1H), 5.84 (d, J=5.6 Hz, 1H), 4.65 (s, 2H), 4.35-4.26 (m, 1H), 4.02-3.78 (m, 4H), 3.44 (d, J=4.2 Hz, 1E) , 3.25-3.07 (m, 2H), 2.96 (s, 3H), 2.49 (s, 3H), 2.031.87 (m, 4H), 1.33 (d, J=6 .5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₉ ClN ₆ O ₂ S: 465.18; the found value is 465.34.

Example 288 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(cyclopropylamino) pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(cyclopropylamino)pyridine-4 -yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to Example 287, except that the methanamine was replaced by cyclopropylamine. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H, formic acid), 7.73 (d, J=5.6 Hz, 1H), 5.92 (d, J=5, 6 Hz, 1H), 5.92 (d, J=6.5 Hz, 3H), 0.82 (m, 2H), 0.63-0.54 (m, 2H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₃ H ₃₁ ClN ₆ O ₂ S: 491.19; the found value is 491.46.

Example 289 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(dimethylamino) pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2(dimethylamino)pyridine-4 -yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 287, except that methylamine was replaced by dimethylamine. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.42 (s, 1H, formic acid), 7.82 (d, J=5.4 Hz, 1H), 6.16 (d, J=5, 4 Hz, 1H), 6.16 (d, J=4.2 Hz, 1H), 3.15 (m, 2H), 2.97 (s, 6H), 2.49 (s, 3H), 2 .03-1.86 (m, 4H), 1.33 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₂ H ₃₁ ClN ₆ O ₂ S: 479.19; the found value is 479.40.

Example 290 8-yl]-5-methylpyrazin-2-yl}methanol.

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[(3-chloro-2-{2-oxa- 6azaspiro[3.3]heptan-6-yl}pyridin-4-yl)sulfanyl]-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to that of Example 287, except that 3-chloro-2(methylamino )pyridine-4-thiol was replaced by 2-amino-3-chloropyridine-4-thiol. 1H NMR (500 MHz, MeOHd ₄ ) δ 7.59 (d, J=5.6 Hz, 1H), 5.89 (d, J=5.5 Hz, 1H), 4.64 (s, 2H) , 4.30 (qd, J=6.5, 4.1 Hz, 1H), 3.99-3.82 (m, 4H), 3.44 (d, J=4.1 Hz, 1H), 3.13 (dddd, J=34.4, 13.8, 11.1, 2.9 Hz, 2H), 2.49 (s, 3H), 2.00-1.84 (m, 3H), 1.761.69 (m, 1H), 1.32 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C20H28QN6O2S: 451.16; the found value is 451.35.

Synthesis of 2-amino-3-chloropyridine-4-thiol.

Step 1 4-Bromo-3-chloro-2-fluoropyridine (2 g, 9.50 mmol, 1 eq.) was suspended in ammonium hydroxide (10.4 ml, 269 mmol, 28 eq.) in a sealed vessel. The reaction mixture was heated at 115°C for 6 h, cooled to room temperature, diluted with ethyl acetate, washed with brine, dried over Na ₂ SO ₄ , filtered and concentrated under reduced pressure to obtain the product as a white solid (1.85 g , 8.91 mmol, 95% yield. LC-MS (ESI) mass/charge: [M+H] calc. for C ₅ H ₄ BrClN ₂ : 206.92; the found value is 206.6.

Step 2 4-Bromo-3-chloropyridine-2-amine (1.83 g, 8.82 mmol, 1 eq.), Pd ₂ (dba) ₃ (1.04 g, 1.14 mmol,

- 199 041617

0.13 eq.) and Xantphos (1.52 g, 2.64 mmol, 0.3 eq.) were placed in a sealed pressure vessel and suspended in degassed 1,4-dioxane (44.0 ml). Next, 2-ethylhexyl-3-mercaptopropanoate (5.00 ml, 22.0 mmol, 2.5 eq.) and DIPEA (6.11 ml, 35.2 mmol, 4 eq.) were added. The reaction mixture was degassed for ten minutes, then sealed. The reaction mixture was heated at 100°C for 3 h, then cooled and filtered. The filtrate was concentrated under reduced pressure to give a yellow solid. The solid was suspended in heptane (150 ml) and stirred for 15 minutes. The solids were filtered off and suspended in heptane (150 ml) and stirred for 15 minutes. The solids were filtered off and dried under reduced pressure to give the product as a yellow solid (2.97 g, 8.61 mmol, 98% yield). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₆ H ₂₅ ClN ₂ O ₂ S: 345.13; the found value is 345.2. Ή NMR (500 MHz, Chloroform-d) δ 7.84 (d, J=5.4 Hz, 1H), 6.50 (d, J=5.5 Hz, 1H), 5.06-4.80 (m, 2H), 4.02 (dd, J=5.8, 2.4 Hz, 2H), 3.20 (t, J=7.4 Hz, 2H), 2.71 (t, J= 7.4 Hz, 2H), 1.65-1.49 (m, 1H), 1.39-1.18 (m, 8H), 0.990.78 (m, 6H).

Step 3 2-Ethylhexyl-3-((2-amino-3-chloropyridin-4-yl)thio)propanoate (3 g, 8.69 mmol, 1 eq) was dissolved in THF (49.9 ml). The reaction mixture was cooled to -78°C and placed under a nitrogen atmosphere. Potassium tert-butoxide (11.2 ml, 11.2 mmol, 1.3 eq.) was then added. The reaction mixture was stirred at -78° C. for 2 hours. The reaction mixture changed from clear yellow to a thick slurry. The cooled slurry was filtered and the solid washed with THF to give a white solid. Purification by column chromatography (0-20% MeOH/dichloromethane gradient) provided the product as a white solid (0.92 g, 5.72 mmol, 66% yield). LC-MS (ESI) mass/charge: [M+H] calc. for C ₅ H ₅ ClN ₂ S: 160.99; the found value is 160.6. ¹ H NMR (500 MHz, DMSO-d ₆ ) δ 7.03 (d, J=5.3 Hz, 1H), 6.47 (d, J=5.4 Hz, 1H).

Example 291 {3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[(3-chloro-2-{2 -oxa6-azaspiro[3.3]heptan-6-yl}pyridin-4-yl)sulfanyl]-5-methylpyrazin-2-yl}methanol.

Me

O {3-[(3S,4S)-4-Amino-3-methyl-2-κsa-8-azasspiro[4.5]decan-8-yl]-6-[(3-chloro-2-{2-oxa -6azaspiro[3.3]heptan-6-yl}pyridin-4-yl)sulfanyl]-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to that of Example 287, except that the methanamine was replaced by 2- oxa-6-azaspiro[3.3]heptane. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.57 (s, 1H, formic acid), 7.74 (d, J=5.4 Hz, 1H), 6.01 (d, J=5, 4 Hz, 1H), 6.01 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₅ H33ClN ₆ O3S: 533.20; the found value is 533.42.

Example 292 4-yl)pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol.

Me

{3-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-{[3-chloro-2-(morpholin-4yl) pyridin-4-yl]sulfanyl}-5-methylpyrazin-2-yl}methanol was synthesized by a method similar to the method in example 287, except that the methanamine was replaced by morpholine. 1H NMR (500 MHz, MeOH-d ₄ ) δ 7.90 (d, J=5.4 Hz, 1H), 6.29 (d, J=5.4 Hz, 1H), 6.29 (d, -MS (ESI) mass/charge: [M+H] calculated for C ₂₄ H3 ₃ ClN ₆ O ₃ S: 521.20, found value 521.1.

The following examples were synthesized using a method similar to the method in example 287.

- 200 041617

Table 12 Examples 293-294

Example 295 -yl)thio)-5-methylpyrazin-2-yl)methanol.

_ _{Yag Br o} Pd2(dba)3. (1 mol.%)

Stage 1. Synthesis of 4-bromo-3-chloro-2-cyclopropoxypyridine.

Cyclopropanol (82.4 mg, 1.42 mmol) and cesium carbonate (619 mg, 1.90 mmol ). The reaction mixture was stirred in a closed vial at 100°C for 90 min. The resulting reaction mixture was diluted with EtOAc and H ₂ O. The aqueous layer was extracted two more times with EtOAc. The combined organic layers were dried over MgSO ₄ , filtered and concentrated in vacuo. The residue was purified by column chromatography 0-25% EtOAc/heptane to give the desired product, which is 4-bromo-3-chloro-2-cyclopropoxypyridine (50.0 mg, 201 μmol, 21.1%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₈ H ₇ BrClNO: 247.94; the found value is 249.0.

Step 2. Synthesis of tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-4yl)thio)-3 -(hydroxymethyl)-6-methylpyrazin-2-yl)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-yl)carbamate.

4-bromo-3-chloro-2-cyclopropoxypyridine (50 mg, 201 µmol), 2-ethylhexyl-3-mercaptopropanoate (49.1 mg, 221 µmol), Pd ₂ (dba) ₃ (5 .36 mg, 12.0 µmol), Xantphos (11.6 mg, 20.1 µmol) and DIPEA (51.9 mg, 402 µmol). The mixture was evacuated in a centralized vacuum system for 10 min, then degassed 1,4-dioxane (2.01 ml) was added. The reaction mixture was purged with N2 and evacuated three times and then heated to 120° C. for 1.5 hours under microwave conditions. The resulting reaction mixture was filtered through a Celite pad and the filtrate was concentrated in vacuo.

The residue was purified by column chromatography using 0-100% EtOAc/heptanes. Pure fractions were combined and concentrated in vacuo to give the desired product, which is tert-butyl-((3S,4S)-8-(5-((3-chloro-2-((tetrahydro-2H-pyran-4-yl) hydroxy) pyridin-4yl) thio) -3- (hydroxymethyl) -6-methylpyrazin-2-yl) -3-methyl-2-oxa-8-azaspiro[4.5] decan-4-yl) carbamate (55.0 mg , 86.4 µmol, 90.7%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₉ H ₂₈ ClNO ₃ S: 386.15; the found value is 386.30.

Stage 3. Synthesis of 3-chloro-2-cyclopropoxypyridine-4-thiol.

Sodium methoxide (11.1 mg, 206 µmol). The reaction mixture was stirred in a closed vial at room temperature for 1 hour. The resulting reaction mixture was concentrated in vacuo. The residue was purified by column chromatography using 0-10% MeOH/DCM to give the desired product, which is 3-chloro2-cyclopropoxypyridine-4-thiol (18.6 mg, 92.2 μmol, 89.8%). LC-MS (ESI) mass/charge: [M+H] calc. for C ₈ H ₈ ClNOS: 202.00; the found value is 202.1.

Stage 4. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[(3-chloro-2cyclopropoxypyridin-4 -yl)sulfanyl]-5-methylpyrazin-2-yl}methanol.

(3-((3S,4S)-4-amino-3-methyl-2-oxa-8azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2-yl ) methanol (25 mg, 67.6 µmol), 3-chloro-2

- 201 041617 cyclopropoxypyridine-4-thiol (21.3 mg, 101 µmol), Pd ₂ (dba) ₃ (3.02 mg, 6.76 µmol), Xantphos (7.83 mg, 13.5 µmol) and DIPEA (23.4 µl, 135 µmol). The mixture was evacuated in a centralized vacuum system for 10 min, then degassed 1,4-dioxane (675 μl) was added. The reaction mixture was purged with N2 and evacuated three times and then stirred at 110° C. under microwave conditions for 2 hours. The reaction was complete according to LC-MS. The resulting reaction mixture was filtered and then the filtrate was concentrated in vacuo. The residue was purified by preparative HPLC to give the desired product, which is (3((3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-( (3-Chloro-2-cyclopropoxypyridin-4yl)thio)-5-methylpyrazin-2-yl)methanol (14.0 mg, 28.4 µmol, 42.1%), as its formic acid salt. ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H) (formic acid), 7.82 (d, J=5.5 Hz, 1H), 6.29 (d, J= 5.5 Hz, 1H), 4.65 (s, 2H), 4.38-4.26 (m, 2H), 3.88 (m, 2H), 3.30-3.10 (m, 4H ), 2.68 (s, 1H), 2.49 (s, 3H), 2.021.65 (m, 4H), 1.29 (d, J=6.5 Hz, 3H), 0.86-0 .70 (m, 4H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₃ H ₃₀ ClN ₅ O ₃ S: 492.18; the found value is 492.42.

Example 296 Synthesis of (R)-(6-(6-amino-2,3-dichloropyridin-4-yl)-3-(1-amino-8-azaspiro[4.5]decan-8yl)-5-methylpyrazin-2 -yl) methanol.

Stage 1. Synthesis of (6-((tert-butoxycarbonyl)amino)-2,3-dichloropyridin-4-yl)boronic acid.

A mixture of tert-butyl-(5,6-dichloro-4-iodopyridin-2-yl)carbamate (2 g, 5.14 mmol) in THF (25.6 ml) was cooled to 0°C under N2 atmosphere. Sodium hydride (240 mg, 10.0 mmol) was added in portions. When hydrogen evolution was complete, the reaction mixture was cooled to -78°C and n-butyl lithium (4.28 ml, 10.7 mmol) was added over a period of 5 minutes. Triethyl borate (1.91 ml, 11.3 mmol) was added and the mixture was stirred at -78°C for an additional 4 hours. Water was then added and the mixture was allowed to warm to 0°C. EtOAc and saturated ammonium chloride solution were added and the phases were separated. The organic phase was washed with additional saturated ammonium chloride solution and brine and dried over Na ₂ SO ₄ and the solvent was evaporated. Purification by column chromatography provided 890 mg (56%) of the desired product. LC-MS (ESI) mass/charge: [M+H -Boc] calc. for C ₁₀ H ₁₃ BCl ₂ N ₂ O ₄ : 206.99, found value 206.9.

Stage 2. Synthesis of (R)-(6-(6-amino-2,3-dichloropyridin-4-yl)-3-(1-amino-8-azaspiro[4.5]decan-8-yl)5-methylpyrazin- 2-yl) methanol.

(6-((tert-Butoxycarbonyl)amino)-2,3-dichloropyridin-4-yl)boronic acid (90.5 mg, 295 µmol), potassium carbonate (108 mg, 788 µmol), [1,1'- bis(diphenylphosphino)ferrocene]dichloropalladium(P), complex with DCM (32.1 mg, 39.4 µmol) and (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6- methylpyrazin2-yl)-8-azaspiro[4.5]decan-1-yl)carbamate (90 mg, 197 µmol) was weighed into a vial provided with a magnetic stirrer and a septum screw cap. The reaction vessel was purged 3 times with N ₂ . MeCN (1.97 ml, degassed with N ₂ bubbling for 1 h) was added to counterbalance N ₂ and the headspace of the reaction vessel was purged 3 times with N ₂ . The mixture was placed in a heating block preheated to 100° C. and stirred vigorously for 1 hour. The reaction mixture was cooled to room temperature and filtered through a celite pad. The filtrate was evaporated to dryness and purified by column chromatography (0-(>99)% EtOAc/heptanes). The purified product was dissolved in MeOH (2 ml). The solution was treated with HCl (4 M in dioxane, 1 ml) at room temperature for 2 hours. Concentration under reduced pressure and purification by preparative HPLC provided 32 mg (37%) of the desired product. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.56 (s, 1H), 6.50 (s, 1H), 4.68 (s, 2H), 3.76 (dd, J=30.5 , 13.6 Hz, 2H), 3.26 (t, J=6.9 Hz, 1H), 3.19-3.11 (m, 2H), 2.32 (s, 3H), 2.28 -2.19 (m, 1H), 1.94-1.69 (m, 6H), 1.62-1.54 (m, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₀ H ₂₆ C ₁₂ N ₆ O: 437.16; the found value is 437.1.

- 202 041617

Example 297 Synthesis of (R)-4-(5-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(hydroxymethyl)-3methylpyrazin-2-yl)-3-chloro-1- methylpyridin-2(1 H)-one.

Ma

Stage 1. Synthesis of 4-bromo-3-chloro-1-methylpyridin-2(1Н)-one.

In a 40 ml screw cap vial with a membrane, 4-bromo-3-chloropyridin-2(1H)-one (600 mg, 2.87 mmol) was dissolved in acetone (2.87 ml) and potassium carbonate (1.57 g , 11.4 mmol) followed by the addition of iodomethane (706 μl, 11.4 mmol). The mixture was heated to 60°C for 24 hours. After cooling to room temperature and filtering through celite, the solvent was removed under reduced pressure and the crude product was purified using column chromatography (0-99% EtOAc/heptanes) to obtain 423 mg (66%) the required product. LC-MS (ESI) mass/charge: [M+H] calc. for C ₆ H ₅ BrClNO: 221.93, found value 221.9.

Step 2. Synthesis of 3-chloro-1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2(1Н)one.

4-Bromo-3-chloro-1-methylpyridin-2(1H)-one (250 mg, 1.12 mmol), [1,1'bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with DCM (56, 6 mg, 69.4 µmol), bis(pinacolato)diboron (426 mg, 1.68 mmol) and potassium acetate (340 mg, 3.47 mmol) were weighed into a 40 ml glass vial provided with a screw cap with a septum and a magnetic stirrer . The reaction vessel was purged 3 times with N2 and dioxane (degassed) (7.46 mL) was added to counterbalance _N2 . The headspace of the reaction vessel was sparged 3 times with N ₂ and the mixture was placed in a preheated heating block (85°C). After stirring overnight, the mixture was filtered through celite and then evaporated to dryness. The crude product was purified by column chromatography (1-(>15)% MeOH/DCM) and then triturated with a small amount of MeOH to give 120 mg (40%) of the desired product as an off-white solid. LC-MS (ESI) mass/charge: [M (boronic acid)-1] calc. for C ₆ H7BClNO ₃ : 187.02, found value 187.6.

Stage 3. Synthesis of (R)-4-(5-(1-amino-8-azaspiro[4.5]decan-8-yl)-6-(hydroxymethyl)-3-methylpyrazin2-yl)-3-chloro-1 - methylpyridin-2(1 H)-one.

(R)-tert-Butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8-azaspiro[4.5]decan-1yl)carbamate (100 mg, 219 µmol), potassium carbonate (121 mg, 876 µmol), [1,1'bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with DCM (35.7 mg, 43.8 µmol) and 6-chloro-1methyl-5-( 4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2(1H)-one (76.5 mg, 284 µmol) was weighed into a 2 drachm vial provided with a magnetic stirrer and screwed membrane cover. The reaction vessel was purged 3 times with N ₂ . MeCN (2.57 ml, degassed with N ₂ sparging for 1 h) was added to counterbalance N ₂ and the headspace of the reaction vessel was purged 3 times with N 2 . This mixture was placed in a heating block preheated to 100° C. and stirred vigorously for 1 h. The reaction mixture was cooled to room temperature and filtered through a Celite pad, followed by concentration under reduced pressure and purification by column chromatography (0-( >99)% EtOAc/heptanes). The purified product was dissolved in MeOH (2 ml). The solution was treated with HCl (4 M in dioxane, 1 ml) at room temperature for 2 h. After removal of the solvent under reduced pressure, the deprotected product was purified by preparative HPLC to give 17 mg (14%) of the desired product. 1H NMR (500 MHz, MeOH-d4) δ 8.53 (s, 1H), 7.74 (dd, J=7.0, 1.0 Hz, 1H), 6.44 (d, J=6, 9 Hz, 1H), 4.69 (s, 2H), 3.86-3.74 (m, 2H), 3.71 (d, J=1.0 Hz, 3H), 3.31-3, 25 (m, 1H), 3.17 (ddt, J=13.4, 11.5, 2.4 Hz, 2H), 2.34 (s, 3H), 2.31-2.20 (m, 1H), 1.95-1.71 (m, 6H), 1.59 (t, J=13.8 Hz, 2H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₈ ClN ₅ O ₂ : 418.20, found value 418.3.

- 203 041617

Example 298 Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[2,3-dichloro6-(methylamino )pyridin-4-yl]-5-methylpyrazin-2-yl}methanol.

1. PdCbdppf CH ₂ Cb MeCN, 100°C, 1 h.

2. HC1 dioxacMeOH q.t., 2 hours

Stage 1. Synthesis of tert-butyl-(5,6-dichloro-4-iodopyridin-2-yl)(methyl)carbamate.

Sodium hydride (149 mg, 6.16 mmol) was suspended in DMA (10.2 ml) and the mixture was cooled to 0°C. At 0°C, a solution of tert-butyl-(5,6-dichloro-4-iodopyridin-2-yl)carbamate (2 g, 5.14 mmol) in DMA (5.14 ml) was added over a period of 5 minutes . After completion of the addition, the reaction mixture was stirred at 0° C. for 5 minutes and then for 1 hour at room temperature. Methyl iodide (425 μl, 6.83 mmol) was added in one portion and the reaction mixture was stirred at room temperature overnight. The reaction mixture was diluted with EtOAc and washed with sodium bicarbonate and brine. The organic phase was separated, dried over Na ₂ SO ₄ , filtered and the solvent was removed under reduced pressure. The residue was purified using column chromatography.

Stage 2. Synthesis of (6-((tert-butoxycarbonyl)(methyl)amino)-2,3-dichloropyridin-4-yl)boronic acid.

A mixture of tert-butyl-(5,6-dichloro-4-iodopyridin-2-yl)(methyl)carbamate (500 mg, 1.24 mmol) in THF (6.19 ml) was cooled to -78°C under N2 . n-Butyl lithium (1.04 ml, 2.60 mmol) was added over a period of 5 minutes and the mixture was allowed to stir at -78° C. for 25 minutes. Triethyl borate (462 μl, 2.72 mmol) was then added and the mixture was stirred at -78°C for an additional 4 hours. Water was added and the mixture was allowed to warm to 0°C. EtOAc and saturated ammonium chloride solution were added and the phases were separated. The organic phase was washed with additional saturated ammonium chloride solution and brine and dried over Na ₂ SO ₄ . After filtration, the solvent was evaporated and the crude product was purified by column chromatography (0-10% MeOH/DCM) to give 310 mg (79%) of the desired product. LC-MS (ESI) mass/charge: [M+H] calc. For CnHi ₅ BCl ₂ N ₂ O ₄ : 321.06, found value 321.2.

Stage 3. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-[2,3-dichloro-6( methylamino)pyridin-4-yl]-5-methylpyrazin-2-yl}methanol.

(3-((3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2yl)methanol (100 mg, 269 µmol), [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with DCM (43.9 mg, 53.8 µmol), potassium carbonate (147 mg, 1.07 mmol) and (6 -((tert-butoxycarbonyl)(methyl)amino)-2,3-dichloropyridin-4-yl)boronic acid (112 mg, 349 μmol) was weighed into a microwave treatment vessel provided with a magnetic stirrer. The reaction vessel was purged 3 times with N ₂ . MeCN (2.68 ml, degassed with N2 sparging for 1 h) was added to counterbalance N2 and the headspace of the reaction vessel was purged 3 times with N ₂ . The mixture was placed in a heating block preheated to 100° C. and stirred vigorously for 3 hours. The reaction mixture was cooled to room temperature and filtered through a Celite pad, followed by concentration under reduced pressure and purification by column chromatography (0-(> 99)% EtOAc/heptanes). After evaporation of the solvent, the purified coupling product was taken up in MeOH (2 ml) and HCl in dioxane (1.00 ml, 4.03 mmol) was added. After stirring for 4 hours at room temperature, the solvent was removed under reduced pressure and the crude product was purified by preparative HPLC to give 17 mg (14%) of the desired product. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.56 (s, 1H), 6.44 (s, 1H), 4.69 (s, 2H), 4.34-4.27 (m, 1H ), 3.93 (d, J=8.9 Hz, 1H), 3.82 (d, J=8.8 Hz, 1H), 3.73-3.64 (m, 2H), 3.27 (d, J=4.5 Hz, 1H), 3.21-3.13 (m, 1H), 3.12-3.04 (m, 1H), 2.90 (s, 3H), 2, 32 (s, 3H), 1.97 (dt, J=13.9, 9.9 Hz, 2H), 1.85 (d, J=13.3 Hz, 1H), 1.75 (d, J =12.9 Hz, 1H), 1.30 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₈ C ₁₂ N ₆ O ₂ : 467.18, found value 467.3.

- 204 041617

Example 299 4-yl)-5-methylpyrazin-2-yl}methanol.

O

Stage 1. Synthesis of 5,6-dichloro-4-iodopyridine-2-amine.

tert-Butyl-(5,6-dichloro-4-iodopyridin-2-yl)carbamate (2 g, 5.14 mmol) was dissolved in MeOH (20 ml) and HCl (4 M in dioxane) (l) was added. The mixture was stirred at room temperature for 4 hours. The solvent was removed under reduced pressure to give the desired product, pure by NMR (yield 1.5 g, quantitative). LC-MS (ESI) mass/charge: [M+H] calc. for C ₅ H ₃ Cl ₂ IN ₂ : 288.88, found value 288.9.

Stage 2. Synthesis of 2,3-dichloro-4-iodo-6-methoxypyridine.

tert. butyl nitrite (1.18 ml, 10.0 mmol) so as to keep the temperature below 5°C. The resulting mixture was stirred at room temperature overnight. The reaction mixture was quenched by careful addition of water and then concentrated to dryness. The crude mixture was purified by column chromatography to give 381 mg (67%) of the desired product. LC-MS (ESI) mass/charge: [M+H] calc. for C ₆ H ₄ Cl ₂ INO: 303.88, found value 304.0.

Stage 3. Synthesis of (2,3-dichloro-6-methoxypyridin-4-yl)boronic acid.

A mixture of 2,3-dichloro-4-iodo-6-methoxypyridine (215 mg, 707 μmol) in THF (3.53 ml) was cooled to 78° C. under N ₂ atmosphere. n-Butyllithium (592 μl, 1.48 mmol) was added over a period of 5 minutes and the mixture was allowed to stir at -78°C for 25 minutes. Triethyl borate (263 μl, 1.55 mmol) was then added and the mixture was stirred at -78°C for 4 h. Water was then added and the mixture was allowed to warm to 0°C. EtOAc and saturated ammonium chloride solution were added and the phases were separated. The organic phase was washed with additional saturated ammonium chloride solution and brine and dried over Na ₂ SO ₄ and the solvent was evaporated. The crude product was purified by column chromatography to give 124 mg (79%) of the desired product. LC-MS (ESI) mass/charge: [M+H] calc. for C ₆ H ₆ BCl ₂ NO ₃ : 220.98, found value 221.0.

Stage 4. Synthesis of {3-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(2,3-dichloro-6methoxypyridine- 4-yl)-5-methylpyrazin-2-yl}methanol.

(2,3-Dichloro-6-methoxypyridin-4-yl)boronic acid (63.0 mg, 284 µmol), potassium carbonate (121 mg, 876 µmol), [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium (P), complex with DCM (35.7 mg, 43.8 µmol) and (R)-tert-butyl-(8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)- 8-azaspiro[4.5]decan1-yl)carbamate (100 mg, 219 µmol) was weighed into a 2 dram vial provided with a septum screw cap and magnetic stirrer. The reaction vessel was purged 3 times with N ₂ . MeCN (2.18 ml, degassed with N2 sparging for 1 h) was added to counterbalance N2 and the headspace of the reaction vessel was purged 3 times with N ₂ . The mixture was placed in a heating block preheated to 100° C. and stirred vigorously for 3 hours. The reaction mixture was cooled to room temperature and filtered through a celite pad. The filtrate was evaporated to dryness and purified by preparative HPLC to give 15.8 mg (17%) of the desired product. ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.57 (s, 1H), 6.86 (s, 1H), 4.69 (s, 2H), 4.32-4.25 (m, 1H), 3.98 (s, 3H), 3.91 (d, J=8.8 Hz, 1H), 3.79 (d, J=8.7 Hz, 1H), 3.69 (t, J=14.2Hz, 2H), 3.26-3.04(m, 3H), 2.30(s, 3H), 1.96(dt, J=21.2, 10.2Hz, 2H ), 1.81 (d, J=13.6 Hz, 1H), 1.74 (d, J=12.8 Hz, 1H), 1.28 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₁ H ₂₇ Cl ₂ N ₅ O ₃ : 468.16, found value 468.4.

Example 300 Synthesis of 3-{5-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6(hydroxymethyl)-3-methylpyrazin- 2-yl}-2-chlorobenzonitrile.

Stage 1. Synthesis of 2-chloro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzonitrile.

3-Bromo-2-chlorobenzonitrile (500 mg, 2.30 mmol), bis(pinacolato)diboron (741 mg, 2.92 mmol), [1,1'-205 041617 bis(diphenylphosphino)ferrocene]dichloropalladium(11) , complexed with DCM (93.9 mg, 115 μmol) and potassium acetate (689 mg, 7.03 mmol) were weighed into a 40 ml vial provided with a Teflon/rubber screw cap and a magnetic stirrer. The reaction vessel was purged 3 times with N ₂ , dioxane (degassed) (18.4 mL) was added to counterbalance N 2 and the headspace of the reaction vessel was purged more than 3 times with N ₂ . The reaction mixture was placed in a heating block preheated to 85° C. and stirred vigorously at this temperature for 2.5 hours. After cooling to room temperature, the mixture was filtered through Celite, the filtrate was evaporated to dryness, and the crude product was purified by column chromatography. (0-99% EtOAc/heptanes) to give 370 mg (61%) of the desired product. LC-MS (ESI) mass/charge: [M+H] calc. for Ci3Hi ₅ BClNO ₂ : 264.10, found value 263.8.

Stage 2. Synthesis of (2-chloro-3-cyanophenyl)boronic acid.

Sodium periodate (375 mg, 1.76 mmol) and ammonium acetate (135 mg, 1.76 mmol) were added to a stirred solution of 2-chloro-3-(4,4,5,5-tetramethyl-1,3,2- dioxaborolan-2-yl)benzonitrile (155 mg, 588 µmol) in acetone (3.92 ml) and water (1.96 ml). The resulting suspension was stirred overnight at room temperature. The mixture was diluted with water and thoroughly extracted with EtOAc. After removing the solvent under reduced pressure, the crude product was purified by column chromatography (0-25% MeOH/DCM) to give 281 mg (69%) of the desired product. LC-MS (ESI) mass/charge: [M-N] calc. for C ₇ H ₅ BClNO ₂ : 180.00, found value 180.2.

Stage 3. Synthesis of 3-{5-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6(hydroxymethyl)-3-methylpyrazin- 2-yl}-2-chlorobenzonitrile.

(3-((3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-bromo-5-methylpyrazin-2yl)methanol (100 mg, 269 µmol), potassium carbonate (147 mg, 1.07 mmol), [1,1'bis(diphenylphosphino)ferrocene]dichloropalladium(II), complex with DCM (43.9 mg, 53.8 µmol) and (2- chloro-3-cyanophenyl)boronic acid (63.3 mg, 349 µmol) was weighed into a 2 dram vial provided with a septum screw cap and magnetic stirrer. The reaction vessel was sparged 3 times with N ₂ . MeCN (2.68 ml, degassed with N ₂ sparging for 1 h) was added to counterbalance N 2 and the headspace of the reaction vessel was purged 3 times with N 2 . The mixture was placed in a heating block preheated at 120° C. and stirred vigorously for 3 hours. The reaction mixture was cooled to room temperature and filtered through a celite pad. The filtrate was evaporated to dryness and purified by preparative HPLC to give 33.7 mg (29%) of the desired product. 1H NMR (500 MHz, MeOH-d ₄ ) δ 8.55 (s, 1H), 7.93 (dd, J=1.1, 1.6 Hz, 1H), 7.75 (dd, J=1 .1, 1.7 Hz, 1H), 7.64 (t, J=7.7 Hz, 1H), 4.70 (s, 2H), 4.34-4.28 (m, 1H), 3 .95 (d, J=8.9 Hz, 1H), 3.84 (d, J=9.0 Hz, 1H), 3.78-3.68 (m, 3H), 3.22-3, 13 (m, 1H), 3.10 (t, J=10.9 Hz, 1H), 2.28 (d, J=1.7 Hz, 3H), 2.03-1.95 (m, 2H ), 1.87 (d, J=13.7 Hz, 1H), 1.76 (d, J=13.3 Hz, 1H), 1.31 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₂ H ₂₆ ClN ₅ O ₂ : 428.19, found value 428.1.

Example 301 Synthesis of 1-(3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl) ethane-1,2-diol.

Stage 1. Synthesis of tert-butyl-(R)-(8-(5-((2,3-dichlorophenyl)thio)-6-methyl-3-vinylpyrazin-2-yl)-8azaspiro[4.5] decan-1 - silt) carbamate.

(R)-tert-butyl-(8-(3-bromo-5-((2,3-dichlorophenyl)thio)-6-methylpyrazin-2yl)-8-azaspiro[4.5]decan-1 -yl)carbamate (100 mg, 0.1659 mmol, examples 43 and 44), MIDA vinylboronic acid ester (45.5 mg, 0.2488 mmol) and [1,1'bis(diphenylphosphino)ferrocene]dichloropalladium(P ), complexed with DCM (13.5 mg, 0.01658 mmol). The vial was then purged with nitrogen before degassed 1,4-dioxane (1.65 ml) was added to the vial and the resulting mixture was stirred at room temperature for 10 minutes. At the end of this time, a solution of potassium phosphate (211 mg, 0.9954 mmol, 6 eq.) in water (330 μl) was added to the vial, which was then placed in a heating bath at 90° C. and stirring was ensured. After 2 h the reaction mixture was cooled to room temperature and diluted with EtOAc (20 ml) and

- 206 041617 water (5 ml). The layers were separated and the organic phase was washed successively with water (5 ml) and brine (5 ml). The washed organic phase was then dried over sodium sulfate. The dried solution was then filtered and the filtrate was concentrated to give an orange oil. This oil was purified by column chromatography to give tert-butyl-(R)-(8-(5-((2,3dichlorophenyl)thio)-6-methyl-3-vinylpyrazin-2-yl)-8-azaspiro[4.5 ]decan-1-yl)carbamate as a neon yellow oil (46.5 mg, 51% yield). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₇ H ₃₄ Cl ₂ N ₄ O ₂ S: 549.2; the found value is 549.5.

Stage 2. Synthesis of tert-butyl-((1R)-8-(5-((2,3-dichlorophenyl)thio)-3-(1,2-dihydroxyethyl)-6methylpyrazin-2-yl)-8-azaspiro[ 4.5]decan-1-yl)carbamate.

A 4 ml vial was charged with AD-mix-beta (118 mg), t-BuOH (0.5 ml) and water (0.5 ml). The resulting orange solution was cooled to 0°C and a solution of (R)-tert-butyl-(8-(5-((2,3dichlorophenyl)thio)-6-methyl-3-vinylpyrazin-2-yl) was added to the vial -8-azaspiro[4.5]decan-1-yl)carbamate (46.5 mg, 0.08461 mmol, 1 eq.) in t-BuOH (0.5 mL). The resulting mixture was allowed to stir at 4°C. After stirring for 96 h, the reaction mixture was partitioned between EtOAc (10 ml) and water (5 ml). The layers were separated and the organic phase was washed successively with water (5 ml) and brine (5 ml). The washed organic solution was dried over sodium sulfate, filtered and concentrated to an orange-brown oil. This crude material was carried to the next step without further characterization or purification.

Stage 3. Synthesis of 1-(3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6-((2,3-dichlorophenyl)thio)-5methylpyrazin-2-yl) ethane-1,2-diol.

A 2 ml vial was charged with tert-butyl-((1R)-8-(5-((2,3-dichlorophenyl)thio)-3-(1,2-dihydroxyethyl)-6methylpyrazin-2-yl)-8-azaspiro [4.5]decan-1-yl)carbamate (24.5 mg, 0.042 mmol, 1 eq.), dioxane (2 ml) and HCl in dioxane (4 M, 2 ml). After stirring for 2 h, the reaction mixture was concentrated under reduced pressure to a yellow-orange solid. This crude residue was purified by preparative HPLC to give 1-(3-((R)-1-amino-8-azaspiro[4.5]decan-8-yl)-6((2,3-dichlorophenyl)thio)-5 -methylpyrazin-2-yl)ethane-1,2-diol (2.1 mg, 11% yield). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₈ Cl ₂ N ₄ O ₂ S: 483.1; the found value is 483.3.

Example 302 Synthesis of (3-((3R,4R)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazine -2-yl)methanol.

Stage 1. Synthesis of methyl-(R)-2-((tert-butyldimethylsilyl)oxy)propanoate.

A dry 500 ml vial was charged with imidazole (6.53 g, 96.0 mmol, 2 eq) and DCM (240 ml) before being cooled to 0°C. After cooling, (R)-methyl-2hydroxypropanoate (5 g, 48.0 mmol, 1 eq.) and TBSCl (9.40 g, 62.4 mmol, 1.3 eq.) were successively added to the solution and the resulting resulting mixture to room temperature. After stirring for 21 hours, the reaction mixture was filtered and the solid was washed with DCM. The combined filtrate was washed successively with 1M HCl (100 ml), saturated aqueous sodium bicarbonate (100 ml) and brine (100 ml). The washed organic solution was then dried over sodium sulfate, filtered and concentrated to give methyl (R)-2-((tert-butyldimethylsilyl)oxy)propanoate as a clear colorless oil (10.4 g, 100% yield). This material was carried to the next step without further characterization or purification.

Step 2. Synthesis of (R)-2-((tert-butyldimethylsilyl)oxy)propanal.

A dry 200 ml vial was charged with (R)-methyl-2-((tert-butyldimethylsilyl)hydroxy) propanoate (1 g, 4.57 mmol, 1 eq.) and DCM (45.6 ml) and the resulting solution was cooled down to -78°C. After cooling, diisobutylaluminum hydride (1 M in DCM, 6.85 ml, 6.85 mmol, 1.5 eq.) was added dropwise to the clear solution, then allowed to stir at -78°C. After stirring for 3 h, the reaction mixture was quenched by adding a saturated aqueous solution of Rochelle's salt (40 ml) at -78°C and then allowing the solution to warm to room temperature over 1 h. After this time, the reaction mixture was transferred to a separating funnel and layers shared. The aqueous phase was then washed with DCM (2x40 ml) and the combined organic extracts were washed with brine. The washed organic solution was then dried over sodium sulfate, filtered and concentrated to a clear colorless oil. This oil was carried to the next step without further characterization or purification.

Step 3. Synthesis of 1-(tert-butyl)-4-ethyl-4-((2R)-2-((tert-butyldimethylsilyl)oxy)-1hydroxypropyl)piperidine-1,4-dicarboxylate.

A dry 50 ml vial was loaded with THF (15.2 ml) and cooled to 0°C. After cooling, LDA (6.84 ml, 6.84 mmol, 1.5 eq) was added to the vial to give an opaque yellow solution. To this solution was added 1-tert-butyl-4-ethylpiperidine-1,4-dicarboxylate (1.17 mL, 4.78 mmol, 1.05 eq.) dropwise. After completion of this addition, the reaction mixture was allowed to stir at 0° C. for 30 minutes. At the end of this time, (R)-2((tert-butyldimethylsilyl)oxy)propanal (860mg, 4.56mmol, 1eq) in THF (2+2mL per wash) was added dropwise to the reaction mixture and stirred the resulting mixture for 1 h at 0°C. The reaction mixture was then heated to 23°C and stirred for 1 h. After this time, the reaction mixture was quenched by adding saturated aqueous NaHCO ₃ :water (1:4, 10 mL) at 23°C. The resulting biphasic mixture was transferred to a separating funnel and the layers were separated. The aqueous phase was then extracted with EtOAc (3x10 ml) and the combined organic extracts were dried over sodium sulfate, filtered and concentrated to a yellow oil. This oil was purified by column chromatography to give 1-(tert-butyl)-4-ethyl 4-((2R)-2-((tert-butyldimethylsilyl)oxy)-1-hydroxypropyl)piperidine-1,4-dicarboxylate (1, 17 g, 58% yield over 3 steps). LC-MS (ESI): mass/charge: [M+Na] calc. for C ₂₂ H ₄₃ NO ₆ Si: 468.3; the found value is 468.4.

Step 4. Synthesis of tert-butyl 4-((2R)-2-((tert-butyldimethylsilyl)oxy)-1-hydroxypropyl)-4(hydroxymethyl)piperidine-1-carboxylate.

A dry 50 ml vial was charged with 1-tert-butyl-4-ethyl-4-((2R)-2-((tert-butyldimethylsilyl)oxy)-1hydroxypropyl)piperidine-1,4-dicarboxylate (1.17 g, 2 .62 mmol, 1 eq.) and THF (13.1 ml) to give an opaque colorless solution. To this solution was added lithium borohydride (2 M in THF, 1.96 mL, 3.93 mmol, 1.5 eq.) at room temperature and the resulting clear colorless solution was allowed to stir. After 72 h, the reaction mixture was cooled to 0°C and saturated aqueous sodium bicarbonate:water (1:2, 3.25 ml) was added to quench the reaction mixture. Gas evolution was observed and stirring was continued until gas evolution ceased. After this time, the reaction mixture was diluted with EtOAc (10 ml) and the layers were separated. The aqueous phase was then extracted with EtOAc (3x10 ml). The combined organic extracts were dried over sodium sulfate, filtered and concentrated to a colorless, partially opaque oil which was used directly in the next step without further purification.

Step 5. Synthesis of tert-butyl 4-((2R)-1,2-dihydroxypropyl)-4-(hydroxymethyl)piperidine-1carboxylate.

A 20 ml plastic vial was sequentially charged with tert-butyl-4-((2R)-2-((tert-butyldimethylsilyl)oxy)-1-hydroxypropyl)-4-(hydroxymethyl)piperidine-1-carboxylate (1.05 g, 2. 60 mmol, 1 eq.), THF (8.66 ml) and tetrabutylammonium fluoride (3.90 ml, 3.90 mmol, 1.5 eq.) at room temperature. After stirring for 3 hours, the reaction mixture was quenched by adding saturated aqueous sodium bicarbonate:water (1:2, 2.5 ml). The mixture was then diluted with EtOAc (10 ml) and the layers were separated. The aqueous phase was then extracted with EtOAc (3x10 ml) and the combined organic extracts were washed with brine, dried over sodium sulfate, filtered and concentrated to give a crude oil. This oil was purified by column chromatography to give tert-butyl 4-((2R)-1,2-dihydroxypropyl)-4(hydroxymethyl)piperidine-1-carboxylate (625 mg, 2.16 mmol, 83% yield in 2 stage) in the form of a clear sticky oil.

Step 6. Synthesis of tert-butyl-(3R)-4-hydroxy-3-methyl-2-oxa-8-azaspiro[4.5]decane-8-carboxylate.

A dry 50 ml vial was loaded with sodium hydride (300 mg, 7.52 mmol, 3.5 eq.) and purged with nitrogen. THF (10 ml) was then added to the vial and the resulting slurry was cooled to 0°C. After cooling, a solution of tert-butyl 4-((2R)-1,2-dihydroxypropyl)-4(hydroxymethyl)piperidine-1-carboxylate (625.5 mg, 2.15 mmol, 1 eq.) was added dropwise to the slurry. in THF (4+2 ml per wash). Immediately after this addition, a solution of 4-methylbenzene-1sulfonyl chloride (409 mg, 2.15 mmol, 1 eq.) in THF (1 ml + 1 ml per wash) was added dropwise to the slurry. The resulting mixture was allowed to stir for 1 hour at 0°C, after which the reaction mixture was cooled to 20°C and quenched by adding saturated aqueous ammonium chloride (1 ml).

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The resulting mixture was vigorously stirred for 10 minutes before additional saturated aqueous ammonium chloride solution (5 ml) and brine (5 ml) were added to the vial. The resulting mixture was diluted with EtOAc (10 ml) and the layers were separated. The aqueous phase was then extracted with EtOAc (3x10 ml). The combined organic extracts were then dried over sodium sulfate, filtered and concentrated to an oil mixed with a white solid. This mixture was dissolved in DCM and filtered and the oil thus obtained was concentrated and used directly in the next step without further purification.

Step 7. Synthesis of tert-butyl-(R)-3-methyl-4-oxo-2-oxa-8-azaspiro[4.5]decane-8-carboxylate.

A dry 25 ml vial was charged with tert-butyl-(3R)-4-hydroxy-3-methyl-2-oxa-8-azaspiro[4.5]decan8-carboxylate (570 mg, 2.13 mmol, 1 eq.) and DCM (5.32 ml) and the resulting solution was cooled to 0°C. After cooling, Dess-Martin periodinane (1.17 g, 2.76 mmol, 1.3 eq.) was added as a solid in one portion and the resulting mixture was allowed to stir at 0°C. After stirring for 2 hours, the reaction mixture was concentrated and the crude material was diluted with DCM. The resulting mixture was filtered and the filtrate was concentrated. The crude residue was purified by column chromatography to give tert-butyl-(R)-3methyl-4-oxo-2-oxa-8-azaspiro[4.5]decan-8-carboxylate (439 mg, 1.63 mmol, 77% yield 2 steps) as a clear, colorless oil. LC-MS (ESI): mass/charge: [M+Na] calc. for C ₁₄ H ₂₃ NO ₄ : 292.2; the found value is 292.2.

Step 8. Synthesis of tert-butyl-(3R,4S)-4-(((R)-tert-butylsulfinyl)amino)-3-methyl-2-oxa-8azaspiro[4.5]decan-8-carboxylate and tert-butyl -(3R,4R)-4-(((R)-tert-butylsulfinyl)amino)-3-methyl-2oxa-8-azaspiro [4.5]decane-8-carboxylate.

A dry 15 ml pressure vessel was charged with titanium(IV) ethanolate (1.35 ml, 6.48 mmol, 4 eq.) followed by the sequential addition of a solution of tert-butyl-(R)-3-methyl-4-oxo-2 -oxa-8azaspiro[4.5]decane-8-carboxylate (439 mg, 1.62 mmol, 1 eq.) in THF (5.40 mL) and (R)-2-methylpropane-2sulfinamide (392 mg, 3.24 mmol, 2 eq.). The pressure vessel was then sealed with a screw cap and the pale yellow solution heated to 90°C. After stirring for 23 h, the reaction mixture was cooled to -10°C and MeOH (540 μl) was added dropwise to the yellow solution. Then lithium borohydride (810 μl, 1.62 mmol, 1 eq.) was added dropwise and the resulting opaque yellow solution was allowed to stir at -10°C. After stirring for 1 h, the reaction mixture was then quenched at -5°C by adding saturated aqueous ammonium chloride solution (~2 ml) followed by dilution with EtOAc (10 ml). The diluted milky white mixture was then warmed to room temperature with vigorous stirring for 30 minutes. At the end of this time, the mixture was filtered through a Celite pad and the clear, colorless filtrate was concentrated to a pale yellow oil with some solids present. This crude material was purified by column chromatography to give t-butyl-(3R,4S)-4-(((R)-t-butylsulfinyl)amino)-3-methyl-2-oxa-8azaspiro[4.5]decane-8 -carboxylate (235.8 mg, 39% yield) and tert-butyl-(3R,4R)-4-(((R)-tert-butylsulfinyl)amino)-3-methyl-2-oxa-8-azaspiro[4.5] decane-8-carboxylate (190.1 mg, 31% yield) as a white solid and a clear oil, respectively. LC-MS (ESI): mass/charge: [M+Na] calc. for C ₁₈ H ₃₄ N ₂ O ₄ S: 397.2; the found value is 397.2.

Step 9. Synthesis of (3R,4R)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-amine.

(3R,4R)-4-(((R)-tert-butylsulfinyl)amino)-3-methyl-2-oxa-8azaspiro[4.5]decan-8-carboxylate (190.1 mg, 0 .5072 mmol, 1 eq.) and MeOH (1.01 ml). To this solution was added HCl in dioxane (4 M, 1.26 ml, 5.07 mmol, 10 eq.) and then the vial was sealed and heated to 50°C. After stirring for 2 hours, the solution was concentrated and used directly in the next reaction without further purification.

Step 10 Synthesis of (3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)methanol

A solution of ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (1.59 g, 4.61 mmol, 1 eq.) in THF (14 ml) was cooled to 0°C . After cooling, DIBAL-H (1 M in hexane, 13.8 ml, 13.8 mmol, 3 eq.) was added dropwise and the reaction mixture was allowed to warm to room temperature. After 30 min the reaction mixture was diluted with diethyl ether and cooled to 0°C. The reaction mixture was then quenched by successively adding water (0.55 ml), 15% NaOH aqueous solution (0.55 ml) and water (1.4 ml). The resulting mixture was stirred for 30 minutes before the mixture was filtered and the filtrate was concentrated. The crude residue thus obtained was dissolved in DCM (30 ml) and washed successively with water (20 ml) and brine (50 ml). The aqueous washes were re-extracted with DCM and the combined organic layers were concentrated under reduced pressure. The crude residue thus obtained was purified by column chromatography to obtain (3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazin-2yl)methanol (0.99 g, 71% yield). ¹ H NMR (300 MHz, DMSO-d ₆ ) δ 7.82 (dd, J=7.8, 1.8 Hz, 1H), 7.55 (t, J=7.7 Hz, 1H), 7 .49 (dd, J=7.6, 1.8Hz, 1H), 5.50 (t, J=6.0Hz, 1H), 4.69 (d, J=6.0Hz, 2H) , 2.32 (s, 3H).

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Step 11. Synthesis of (3-((3R, 4R)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazine -2-yl)methanol.

(3R,4R)-3-methyl-2-oxa-8-azaspiro[4.5]decan-4-amine (86.3 mg, 0.5068 mmol, 1.5 eq.), ( 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl)methanol (102 mg, 0.3378 mmol, 1 eq.), DMA (3.37 ml) and N,N-diisopropylethylamine (557 µl, 3.37 mmol, 10 eq.). Then the vial was sealed and the reaction mixture was heated to 90°C. After stirring for 36 hours, the reaction mixture was concentrated and the crude residue was purified by preparative HPLC to give (3-((3R,4R)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8 -yl)-6-(2,3-dichlorophenyl)-5methylpyrazin-2-yl) methanol (24 mg, 16% yield over 2 steps). (3-((3R,4R)-4-Amino-3-methyl-2-oxa-8azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazin-2-yl )methanol was isolated as its formate salt. ¹ H NMR (500 MHz, MeOH-d ₄ ) δ 8.53 (s, 1H), 7.64 (dd, J=8.1, 1.6, 0.7 Hz, 1H), 7.42 ( t, J=7.9, 0.6 Hz, 1H), 7.34 (dd, J=7.6, 1.7, 0.7 Hz, 1H), 4.68 (s, 2H), 4 .29 (qd, J=6.5, 4.2Hz, 1H), 3.94 (d, J=9.0Hz, 1H), 3.83 (d, J=9.0Hz, 1H) , 3.83 (d, J=4.3 Hz, 1H), 3.12 (ddd, J=13.7, 10.9, 2.9 Hz, 1H), 3.05 (ddd, J=13 .6, 10.8, 2.7 Hz, 1H), 2.25 (s, 3H), 2.02-1.92 (m, 2H), 1.90-1.83 (m, 1H), 1.77-1.71 (m, 1H), 1.30 (d, J=6.5 Hz, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₁ H ₂₆ Cl ₂ N ₄ O ₂ : 437.1; the found value is 437.3.

Example 303 Synthesis of [3-(4-amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methoxypyrazin2-yl]methanol

CI OMe YY OMe fi I fM 1 1',1 1 yy N Na'_D' ll ^N + PdfPPhjUKaCO^ _c I _N CuCI, NaNOg, HCl ^N .3% MeOH CVI'B(OH) ₂ EUN'toluene Cl * ¹ from 0°C to temperature T ² C| 85°С ψ ² otb'Sdovt.

ΜοΟΆ> formation of phlegm meO^O Me 'O^

Stage 1. Synthesis of methyl 3-amino-6-chloro-5-methoxypyrazine-2-carboxylate.

Sodium metal (0.31 g, 13.5 mmol, 1 eq) was added carefully to anhydrous MeOH (300 ml) at 0° C. and stirred at room temperature until complete dissolution was observed. Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate (3.00 g, 13.5 mmol, 1 eq) was added and the mixture was stirred at reflux for 3 hours. The mixture was cooled to room temperature and the product was filtered to give methyl 3-amino-6-chloro-5-methoxypyrazine-2-carboxylate (2.45 g, 83%), which was used without further purification. 1 H NMR (400 MHz, DMSO-d ₆ ) δ 7.63 (s 2H), 3.97 (s 3H), 3.80 (s 3H).

Stage 2. Synthesis of ethyl 3-amino-6-(2,3-dichlorophenyl)-5-methoxypyrazine-2-carboxylate.

A reaction tube was charged with 3-amino-6-chloro-5-methoxypyrazine-2-carboxylate (1.06 g, 4.87 mmol, 1 eq.), 2,3-dichlorophenylboronic acid (1.39 g, 7.26 mmol, 1.5 eq.) and K2CO3 (3.34 g, 24.2 mmol, 4.96 eq.). Toluene (26.5 ml) and ethanol (35 ml) were added, the mixture was purged with argon and Pd(PPh ₃ ) ₄ (281 mg, 0.24 mmol, 0.05 eq.) was added. The tube was sealed and the reaction mixture was stirred at 85°C overnight. The reaction mixture was concentrated under reduced pressure and the crude material was extracted with ethyl acetate. The organic layers were concentrated and the product was purified by column chromatography (SiO ₂ , 5-20% ethyl acetate in hexane) to give ethyl 3-amino-6(2,3-dichlorophenyl)-5-methoxypyrazine-2-carboxylate (703 mg, 42%). 1H NMR (400 MHz, DMSO-d ₆ ) δ 7.71 (m, 1H), 7.67 (s 1H), 7.48-7.39 (m, 2H), 4.33-4.21 ( m, 2H), 3.88 (s 3H), 1.27 (t, J=7.1 Hz, 3H).

Stage 3. Synthesis of ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methoxypyrazine-2-carboxylate.

Ethyl 3-amino-6-(2,3-dichlorophenyl)-5-methoxypyrazine-2-carboxylate (379 mg, 1.11 mmol, 1 eq) was dissolved in THF (4.7 ml) and cooled to 5° C. 12 M HCl (1.40 ml) was added dropwise and the resulting solution was stirred for 20 min at 5° C. followed by the addition of NaNO ₂ (305 mg, 4.43 mmol, 4 eq.). The reaction mixture was stirred for 1 h at 5° C. and then CuCl (219 mg, 2.22 mmol, 2 eq.) was added portionwise. THF (1 ml) was added and the reaction mixture was warmed to room temperature and stirred overnight. The product was extracted with ethyl acetate and purified by column chromatography (SiO ₂ , 5% ethyl acetate in hexanes) to give ethyl 3-chloro-6-(2,3dichlorophenyl)-5-methoxypyrazine-2-carboxylate (158 mg, 39%). 1H NMR (400 MHz, DMSO-d ₆ ) δ 7.88-7.62 (m, 1H), 7.54 (s 1H), 7.53 (m, 1H), 4.37 (q, J= 7.1 Hz, 2H), 3.99 (s 3H), 1.32 (t, J=7.1 Hz, 3H).

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Step 4 Synthesis of ethyl 3-{4-[(tert-butoxycarbonyl)amino]-4-methylpiperidin-1-yl}-6-(2,3dichlorophenyl)-5-methoxypyrazine-2-carboxylate.

Ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methoxypyrazine-2-carboxylate (158 mg, 0.44 mmol, 1 eq), tert-butyl-(4-methylpiperidin-4-yl) carbamate (141 mg, 0.7 mmol, 1.5 eq.) and DIPEA (0.15 ml, 0.9 mmol, 2 eq.) were dissolved in DMF (3.16 ml) in a glass sealed reactor. The reaction mixture was stirred at 85°C overnight. After cooling to room temperature, water was added and the product was purified by column chromatography (SiO ₂ , 0-20% ethyl acetate in hexane) to give ethyl 3-{4-[(tert-butoxycarbonyl)amino]-4-methylpiperidine-1- yl}-6-(2,3-dichlorophenyl)-5methoxypyrazine-2-carboxylate (210 mg, 89%). 1H NMR (400 MHz, DMSO-d ₆ ) δ 7.70 (dd, J=6.9, 2.7 Hz, 1H), 7.48-7.40 (m, 2H), 6.65 (s 1H), 4.27 (q, J=7.0 Hz, 2H), 3.88 (s 3H), 3.61 (m, 2H), 2.14 (m, 2H), 1.57-1 .48 (m, 2H), 1.41 (s, 9H), 1.32-1.25 (m, 6H).

Step 5. Synthesis of ethyl 3-(4-amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methoxypyrazine2-carboxylate.

Ethyl 3-{4-[(tert-butoxycarbonyl)amino]-4-methylpiperidin-1-yl}-6-(2,3-dichlorophenyl)-5methoxypyrazine-2-carboxylate solution (214 mg, 0.40 mmol, 1 eq.) in DCM (4 ml) was cooled to 0°C and then gaseous HCl was bubbled through the solution. After 40 minutes the reaction mixture was warmed to room temperature and the solvent was evaporated to give the crude product. Water (10 ml) was added to the residue and the resulting solution was cooled. Saturated NaHCO ₃ solution was added to adjust the pH to approximately 9. The product was extracted with ethyl acetate and the combined organic extracts were concentrated under reduced pressure to give ethyl 3-(4-amino-4methylpiperidin-1-yl)-6-(2,3-dichlorophenyl) -5-methoxypyrase n-2-carboxylate (178 mg, 100%) as a light orange oil used without further purification. 1 H NMR (400 MHz, DMSO-d ₆ ) δ 7.70 (m, 1H), 7.44-7.43 (m, 2H), 4.27 (q, J=7.1 Hz, 2H), 3.88 (s 3H), 3.53 (m, 4H), 1.63-1.42 (m, 4H), 1.28 (t, J=7.1 Hz, 3H), 1.11 ( s3H).

Step 6. Synthesis of [3-(4-amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methoxypyrazin-2yl]methanol.

Solution of ethyl 3-(4-amino-4-methylpiperidin-1-yl)-6-(2,3-dichlorophenyl)-5-methoxypyrazine n-2carboxylate (172 mg, 0.39 mmol, 1 eq.) in THF (3 ml) was cooled to -5°C and 1 M DIBAL-H solution (1 M in hexanes, 1.17 ml, 1.17 mmol, 3 eq.) was added dropwise. After the addition, the reaction mixture was warmed to room temperature. After 20 min the reaction mixture was diluted with Et ₂ O (5 ml) and cooled. The reaction mixture was quenched by sequential addition of H ₂ O (0.05 ml), 15% NaOH solution (0.05 ml) and H ₂ O (0.12 ml). The resulting suspension was stirred at room temperature for 20 minutes and then filtered and the filter cake was washed with Et ₂ O. The filtrate was concentrated under reduced pressure to give a crude product which was purified by column chromatography to give [3-(4- amino-4-methylpiperidin1-yl)-6-(2,3-dichlorophenyl)-5-methoxypyraz in-2-yl]methanol (76 mg, 49%). 1H NMR (400 MHz, DMSO-d ₆ ) δ 7.67 (dd, J=6.9, 2.6 Hz, 1H), 7.46-7.42 (m, 2H), 5.23 (t , J=5.5 Hz, 1H), 4.47 (d, J=5.2 Hz, 2H), 3.85 (s, 3H), 3.60-3.45 (m, 4H), 1 .63-1.45 (m, 4H), 1.12 (s 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₁₈ H ₂₂ Cl ₂ N ₄ O ₂ : 397.1; the found value is 397.6.

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Example 304 Synthesis of {6-[(2-amino-3-chloropyridin-4-yl)sulfanyl]-3-[(1R,3R)-1-amino-3cyclopropoxy-8-azaspiro[4.5]decan-8-yl ]-5-methylpyrazin-2-yl}methanol.

Stage

1. Synthesis of tert-butyl-(1R,3R)-1-(((R)-tert-butylsulfinyl)amino)-3-(vinyloxy)-8azaspiro[4.5]decane-8-carboxylate.

In N2 medium, 1,10-phenanthroline (289 mg, 1.60 mmol, 0.12 eq.) and Pd(OAc)2 (299 mg, 1.33 mmol, 0.1 eq.) were stirred in 1-vinyloxybutane ( 53 g, 534 mmol, 68.6 ml, 40 eq) for 10 min. Then tert-butyl-(1R,3R)-1-(((R)-tert-butylsulfinyl)amino)-3-hydroxy-8-azaspiro[4.5]decan-8carboxylate (5 g, 13.3 mmol, 1 eq.) and triethylamine (1.35 g, 13.3 mmol, 1.86 ml, 1 eq.). The resulting reaction mixture was heated to 75° C. for 20 hours. The reaction mixture was concentrated in vacuo to give the crude product. The crude product was purified using a silica gel flash chromatography column (petroleum ether/ethyl acetate 1:0 to 0:1) to give t-butyl-(1R,3R)-1-(((R)-t-butylsulfinyl)amino) -3-(vinyloxy)-8-azaspiro[4.5]decane-8-carboxylate (4 g, 9.99 mmol, 75% yield) as a yellow oil. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₃₇ N ₂ O ₄ S: 401.2; the found value is 401.1.

Step 2. Synthesis of tert-butyl-(1R,3R)-1-(((R)-tert-butylsulfinyl)amino)-3-cyclopropoxy-8azaspiro[4.5]decane-8-carboxylate.

Two equivalent batches were prepared in parallel. To a solution of diethylzinc (1 M, 14.98 ml, 3 eq.) in dry DCM (20 ml) was added diiodomethane (8.02 g, 29.96 mmol, 2.42 ml, 6 eq.) in dry DCM (5 ml) at 0°C for 10 min followed by the addition of tert-butyl-(1R,3R)-1-(((R)-tert-butylsulfinyl)amino)-3-(vinyloxy)-8-azaspiro[4.5]decan- 8-carboxylate (2 g, 4.99 mmol, 1 eq.) in dry DCM (5 ml) under N2 at 0°C, then stirred at 20°C for 14 h. Saturated NH ₄ solution was added to the reaction mixture. Cl (20 ml) and the product was extracted with DCM (2x10 ml). Di-tert-butyl dicarbonate (1.09 g, 4.99 mmol, 1.15 ml, 1 eq.) and NaHCO ₃ (629 mg, 7.49 mmol, 291 μl, 1.5 eq.) were added to the aqueous phase. , then ensured the mixing of the resulting mixture at 20°C for 15 hours Two parallel batches were combined. The mixture was extracted with ethyl acetate (20 mlx3), combined all organic phases, washed with saline, dried over Na ₂ SO ₄ then filtered, the filtrate was concentrated under reduced pressure to obtain the crude product. The product was purified by column chromatography (petroleum ether:ethyl acetate=1:0 to 0:1) to give t-butyl-(1R,3R)-1-(((R)-t-butylsulfinyl)amino)-3-cyclopropoxy -8azaspiro[4.5]decane-8-carboxylate (1.6 g, 3.27 mmol, 33% yield, 84% purity) as a colorless oil LC-MS (ESI): Mass/Charge: [M+H] calculated for C ₁₆ H ₃₀ N ₂ O ₂ S: 315.2, found value 315.1.

Stage 3. Synthesis of (1R,3R)-3-cyclopropoxy-8-azaspiro[4.5]decan-1-amine hydrochloride.

To a solution of tert-butyl-(1R,3R)-1-(((R)-tert-butylsulfinyl)amino)-3-cyclopropoxy-8azaspiro[4.5]decan-8-carboxylate (1.5 g, 3.62 mmol , 1 eq.) in EtOAc (20 ml) was added HCl/EtOAc (20 ml) and the resulting reaction mixture was stirred at 25°C for 2 hours. The reaction mixture was concentrated under reduced pressure to obtain hydrochloride (1R,3R)- 3-cyclopropoxy-8-azaspiro[4.5]decan-1-amine (0.892 g, 2.49 mmol, 100% yield, HCl) as a white solid and was used directly in the next step without further purification. LCMS (ESI) mass/charge: [M+H] calc. for C12H22N2O: 211.2; found value: 211.2.

Step 4. Synthesis of ethyl 3-((1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl)-5methylpyrazin-2-carboxylate.

Ethyl-3 -chloro-5-methylpyrazine-2-carboxylate (725 mg, 3.61 mmol, 1 eq.) and DIPEA (3.27 g, 25.3 mmol, 4.41 ml, 7 eq.). The reaction mixture was stirred at 90°C for 16 h, concentrated under reduced pressure to give ethyl 3((1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl)-5 -methylpyrazine-2-carboxylate (1.36 g, crude) as a yellow oil. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₃₀ N ₄ O ₃ : 375.2; found value: 375.1.

Step 5. Synthesis of ethyl 3-((1R,3R)-1-((tert-butoxycarbonyl)amino)-3-cyclopropoxy-8azaspiro[4.5]decan-8-yl)-5-methylpyrazin-2-carboxylate.

To a solution of ethyl 3-((1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl)-5-methylpyrazine2-carboxylate (1.35 g, 3.61 mmol, 1 eq.) in THF (20 ml) was added di-tert-butyl dicarbonate (1.57 g, 7.21 mmol, 1.66 ml, 2 eq.) and triethylamine (368 mg, 3.61 mmol, 501 μl, 1 equivalent). The resulting mixture was stirred at 25° C. for 2 hours. The reaction mixture was concentrated under reduced pressure, and the product was purified by column chromatography (petroleum ether/ethyl acetate=1:0 to 0:1) to give ethyl-3-(( 1R,3R)-1-((tert-butoxycarbonyl)amino)-3-cyclopropoxy-8azaspiro[4.5]decan-8-yl)-5-methylpyrazin-2-carboxylate (0.6 g, 1.26 mmol, yield 35%) as a yellow oil. LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₅ H ₃₈ N ₄ O ₅ ; 475.3; found value: 475.2.

Step 6. Synthesis of tert-butyl-((1R,3R)-3-cyclopropoxy-8-(3-(hydroxymethyl)-6-methylpyrazin-2yl)-8-azaspiro[4.5]decan-1-yl)carbamate.

To a solution of ethyl 3 -((1R,3R)-1 -((tert-butoxycarbonyl)amino)-3-cyclopropoxy-8 azaspiro[4.5]decan-8-yl)-5-methylpyrazin-2-carboxylate (0, 6 g, 1.26 mmol, 1 eq.) in THF (10 ml) was added LiAlH ₄ (2.5 M, 5.06 ml, 10 eq.) at -20°C. The reaction solution was stirred at -20°C for 2 hours, the Reaction mixture was quenched with water (10 ml) and the pH of the reaction mixture was adjusted to 3 with 1 M HCl. The product was extracted with EtOAc (3x30 ml) and the combined organic extracts were washed with brine (1x20 ml) and dried over sodium sulfate. Filtration and concentration under reduced pressure followed by purification by column chromatography provided ((1R,3R)-3-cyclopropoxy-8-(3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan- 1-yl)carbamate (0.435 g, 1.01 mmol, 79% yield) as a yellow oil.

Step 7. Synthesis of tert-butyl-((1R,3R)-8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3cyclopropoxy-8-azaspiro[4.5]decan-1-yl ) carbamate.

To a solution of tert-butyl-((1R,3R)-3-cyclopropoxy-8-(3-(hydroxymethyl)-6-methylpyrazin-2-yl)-8azaspiro[4.5]decan-1-yl)carbamate (435 mg, 1.01 mmol, 1 eq.) in DCM (5 ml) was added NBS (197 mg, 1.11 mmol, 1.1 eq.) at 0°C. The reaction mixture was stirred at 0°C for 5 min and extinguished by adding Na ₂ SO ₃ (10 ml) at 25°C. The reaction mixture was concentrated under reduced pressure and purified by column chromatography (petroleum ether/ethyl acetate, 1:0 to 0:1) to give t-butyl-((1R,3R)-8-(5-bromo-3-( hydroxymethyl)-6-methylpyrazin-2-yl)-3-cyclopropoxy-8-azaspiro[4.5]decan-1-yl)carbamate (0.4 g, 0.782 mmol, 77%) as a yellow solid. 1H NMR (400 MHz, Chloroform-d) δ 4.91 (d, J=9.48 Hz, 1H), 4.61 (s, 2H), 4.10-4.04 (m, 1H), 3.903 .81 (m, 1H), 3.54 (br s, 1H), 3.43-3.30 (m, 2H), 3.24 (d, J=3.09 Hz, 1H), 3.04 -2.89 (m, 2H), 2.53 (s, 3H), 2.302.16 (m, 1H), 1.89-1.68 (m, 6H), 1.60 (d, J=14 .33 Hz, 1H), 1.44 (s, 9H), 0.56 (s, 2H), 0.47 (d, J=5.73 Hz, 2H).

Step 8. Synthesis of tert-butyl-((1R,3R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-3-(hydroxymethyl)6-methylpyrazin-2-yl) -3-cyclopropoxy-8-azaspiro[4.5]decan-1-yl)carbamate.

To a solution of tert-butyl-((1R,3R)-8-(5-bromo-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3cyclopropoxy-8-azaspiro[4.5]decan-1-yl)carbamate (0.3 g, 0.586 mmol, 1 eq.) in dioxane (6 ml) was added 2-amino-3-chloropyridine-4-thiol (188 mg, 1.17 mmol, 2 eq.), Xantphos (67.9 mg, 0.117 mmol, 0.2 eq.), DIPEA (152 mg, 1.17 mmol, 204 ml, 2 eq.) and Pd ₂ (dba) ₃ (53.7 mg, 0.0586 mmol, 0.1 equiv.) in an N2 atmosphere. The reaction mixture was stirred at 110°C for 1 h in an inert atmosphere, diluted with water (6 ml) and was extracted with EtOAc (3x20 ml). The combined organic extracts were washed with brine (1x10 ml), dried over sodium sulfate, filtered and concentrated under reduced pressure to give the crude product. Purification by column chromatography (petroleum ether/ethyl acetate, 1:0 to 0:1) provided tert-butyl-((1R,3R)-8-(5((2-amino-3-chloropyridin-4-yl )thio)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-3-cyclopropoxy-8azaspiro[4.5]decan-1-yl)carbamate (0.3 g, 0.507 mmol, 86%) as a yellow solid substances. LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₈ H ₃₉ ClN ₆ O ₄ S: 591.2; the found value is 591.1.

Step 9. Synthesis of (6-((2-amino-3-chloropyridin-4-yl)thio)-3-((1R,3R)-1-amino-3-cyclopropoxy-8azaspiro[4.5]decan-8-yl )-5-methylpyrazin-2-yl)methanol.

Solution of tert-butyl-((1R,3R)-8-(5-((2-amino-3-chloropyridin-4-yl)thio)-3-(hydroxymethyl)-6

- 213 041617 methylpyrazin-2-yl)-3-cyclopropoxy-8-azaspiro[4.5]decan-1-yl)carbamate (0.34 g, 0.575 mmol, 1 eq.) in HCl/MeOH (10 ml) was stirred at 25°C for 30 min. The reaction mixture was concentrated under reduced pressure and purified by preparative HPLC to give {6-[(2-amino-3chloropyridin-4-yl)sulfanyl]-3-[(1R,3R)-1-amino-3-cyclopropoxy-8 -azaspiro[4.5]decan-8-yl]-5methylpyrazin-2-yl}methanol (0.127 g, 0.247 mmol, 43%) as formate salt. ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 8.53 (s, 1H), 7.61 (d, J=5.62 Hz, 1H), 5.90 (d, J=5.50 Hz , 1H), 4.62 (s, 2H), 4.24-4.21 (m, 1H), 4.04-3.85 (m, 2H), 3.39 (m, 1H), 3 .17-3.14 (m, 2H), 2.48-2.44 (m, 4H), 2.08-2.07 (m, 2H), 1.82-1.76 (m, 4H) , 1.56 (d, J=11.98 Hz, 1H), 0.57-0.49 (m, 4H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂ 3H3iC1N ₆ O ₂ S: 491.2; the found value is 491.1.

Example 305 Synthesis of {3-[(1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl]-6-(2,3dichlorophenyl)-5-methylpyrazin-2-yl }methanol.

Step 1. Synthesis of ethyl 3-((1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin-2- carboxylate.

A mixture of ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (83.4 mg, 0.241 mmol, 1 eq) and (1R,3R)-3-cyclopropoxy-8- azaspiro[4.5]decan-1-amine (59.5 mg, 0.241 mmol, 1 eq.) and DIPEA (93.51 mg, 0.723 mmol, 126.03 μl, 3.0 eq.) in isopropyl alcohol (3 ml ) was heated to 75°C for 10 h. The reaction mixture was diluted with EtOAc (20 ml) and washed with saturated NH ₄ Cl solution (3x10 ml). The combined aqueous phase was re-extracted with EtOAc (3x20 ml) and the combined organic extracts were washed with brine, dried (Na ₂ SO ₄ ), filtered and concentrated in vacuo to obtain the crude product. The crude product was purified by column chromatography (petroleum ether/EtOAc, 1:0 to 0:1) to give ethyl 3((1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan- 8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (60 mg, 41%) as a yellow oil. LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₆ H ₃₂ Cl ₂ N ₄ O ₃ : 519.2; the found value is 519.1.

Stage 2. Synthesis of {3-[(1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl]-6-(2,3dichlorophenyl)-5-methylpyrazin-2-yl }methanol.

Two equivalent batches were prepared in parallel. To a solution of ethyl 3-((1R,3R)-1-amino-3cyclopropoxy-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate ( 30 mg, 0.058 mmol, 1 eq.) in THF (1 ml) at -10°C was added LiAlH ₄ (2.5 M in THF, 231 μl, 10 eq.,). After 5 minutes the reaction mixture was quenched by slowly adding water (2 ml). Two parallel batches were combined, filtered and the solid was washed with MeOH (2 ml) to obtain a solution. The solution was purified by preparative HPLC and then by SFC to give {3[(1R,3R)-1-amino-3-cyclopropoxy-8-azaspiro[4.5]decan-8-yl]-6-(2,3- dichlorophenyl)-5-methylpyrazin-2yl}methanol (9.9 mg, 17%) as starting material. ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 7.62 (d, J=7.94 Hz, 1H), 7.38-7.44 (m, 1H), 7.32-7.35 ( m, 1H), 4.66 (s, 2H), 4.17 (m, 1H), 3.62-3.79 (m, 2H), 2.99-3.15 (m, 3H), 2 .42 (m, 1H), 2.25 (s, 3H), 2.01 (m, 2H), 1.75-1.91 (m, 3H), 1.70 (d, J=13.2 Hz, 1H), 1.46 (d, J=12.1 Hz, 1H), 0.40-0.61 (m, 4H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₄ H ₃₀ Cl ₂ N ₄ O ₂ : 477.2; the found value is 477.1.

- 214 041617

Example 306 Synthesis of (4S)-4-amino-8-[5-(2,3-dichlorophenyl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl]2λ ⁶ -thia-8-azaspiro[4.5] decane-2,2-dione.

Stage 1. Synthesis of methyl-2-(benzylthio)acetate.

To a solution of phenylmethanethiol (33.85 g, 272.4 mmol, 31.9 ml, 1 eq.) and NaH (32.7 g, 817.15 mmol, 60% purity, 3 eq.) in THF (1000 ml) Methyl-2-bromoacetate (50 g, 326.85 mmol, 30.85 ml, 1.2 eq.) was added in one portion at 0° C. under N ₂ atmosphere. The mixture was stirred at 20° C. for 2 hours. The reaction mixture was quenched by dropwise addition of water (400 ml). The product was extracted with ethyl acetate (2x800 ml). The combined organic phase was washed with brine (1x50 ml), dried (Na ₂ SO ₄ ), filtered and concentrated. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, 10:1 to 1:1) to give methyl 2-(benzylthio)acetate (38 g, 193.62 mmol, 71%) as a colorless oil . ¹ H NMR (400 MHz, Chloroform-d) δ 7.33-7.26 (m, 4 H) 7.257.20 (m, 1H), 3.80 (s, 2H), 3.69 (s, 3H ), 3.06 (s, 2H).

Stage 2. Synthesis of 2-(benzylthio)acetaldehyde.

To a solution of methyl 2-(benzylthio)acetate (38 g, 193.62 mmol, 1 eq) in toluene (1000 ml) was added DIBAL-H (1 M, 232.32 ml, 1.2 eq) in one portion. at -78°C under N2 atmosphere. The mixture was stirred at 78°C for 30 min. The reaction mixture was quenched with a saturated aqueous solution of Rochelle's salt (20 ml), diluted with ethyl acetate (50 ml) and stirred at 20°C for 3 h. The quenched reaction mixture was filtered through celite, dried over MgSO ₄ , filtered a second time through celite and concentrated with obtaining 2-(benzylthio)acetaldehyde (32 g, crude) as a colorless oil.

Step 3. Synthesis of 1-(tert-butyl)-4-methyl-4-(2-(benzylthio)-1-hydroxyethyl)piperidine-1,4-dicarboxylate.

To a solution of 1-(tert-butyl)-4-methylpiperidine-1,4-dicarboxylate (29.14 g, 113.23 mmol, 1.00 eq.) was added LiHMDS (1M, 169.85 ml, 1.5 eq. .) in THF (500 ml) at -78°C and the resulting solution was stirred at 20°C for 1 h. ml, 1.7 eq.) at -78°C under N2. The mixture was stirred at 20° C. for 15 hours. The reaction mixture was poured into water (400 ml) and the aqueous phase was extracted with ethyl acetate (3x300 ml). The combined organic phase was washed with brine (40 ml), dried (Na ₂ SO ₄ ), filtered and concentrated. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, 10:1 to 3:1) to give 1-(t-butyl)-4-methyl-4-(2-(benzylthio)-1hydroxyethyl)piperidine -1,4-dicarboxylate (27 g, 64 mmol, 56%) as a light yellow oil.

Step 4. Synthesis of tert-butyl 4-(2-(benzylthio)-1-hydroxyethyl)-4-(hydroxymethyl)piperidine-1carboxylate.

To a solution of 1-(tert-butyl)-4-methyl-4-(2-(benzylthio)-1-hydroxyethyl)piperidine-1,4-dicarboxylate (27 g, 64 mmol, 1.00 eq.) in THF ( 750 ml) LiAlH4 (3.75 g, 98.9 mmol, 1.5 eq.) was added in one portion at 0° C. under N ₂ atmosphere. The mixture was stirred at 0° C. for 3 hours. The reaction mixture was poured into 300 ml 1 M HCl (300 ml) and the aqueous phase was extracted with ethyl acetate (3x500 ml). The combined organic phase was washed with brine (3x10 ml), dried (Na ₂ SO ₄ ) and filtered. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, 5:1 to 0:1) to give tert-butyl-4-(2-(benzylthio)-1-hydroxyethyl)-4-(hydroxymethyl)piperidine -1-carboxylate (4.33 g, 11.35 mmol, 17%) as a colorless oil.

- 215 041617

Step 5. Synthesis of tert-butyl 4-hydroxy-2-thia-8-azaspiro[4.5]decane-8-carboxylate.

To a solution of tert-butyl 4-(2-(benzylthio)-1-hydroxyethyl)-4-(hydroxymethyl)piperidine-1-carboxylate (2.8 g, 7.34 mmol, 1 eq.) in pyridine (80 ml) Tosyl chloride (3.50 g, 18.35 mmol, 2.5 eq.) was added in one portion at 20° C. under N ₂ atmosphere. The mixture was then stirred at 80° C. for 15 hours. The reaction mixture was concentrated in vacuo. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, 6:1 to 1:1) to give tert-butyl 4-hydroxy-2-thia-8azaspiro[4.5]decan-8-carboxylate (0. 91 g, 3.33 mmol, 45% yield as light yellow oil. 1H NMR (400 MHz, Chloroform-d) δ 3.98 (m, 1H), 3.84 (m, 2H), 3.12-2.92 (m, 3H), 2.81-2.73 ( m, 3H), 1.81-1.60 (m, 3H), 1.46 (s, 9H).

Step 6. Synthesis of tert-butyl 4-oxo-2-thia-8-azaspiro[4.5]decane-8-carboxylate.

To a solution of tert-butyl 4-hydroxy-2-thia-8-azaspiro[4.5]decane-8-carboxylate (0.9 g, 3.29 mmol, 1.00 eq.) and Dess-Martin periodinan (1, 95 g, 4.61 mmol, 1.43 ml, 1.4 eq.) in DCM (40 ml) was added NaHCO ₃ (940.26 mg, 11.19 mmol, 435.31 μl, 3.4 eq. .) at 20°C under N2 atmosphere. The mixture was stirred at 20°C for 2 hours. The residue was poured into a saturated solution of Na ₂ S ₂ O ₃ (50 ml) and stirred for 10 minutes. The aqueous phase was extracted with DCM (2x100 ml). The combined organic phase was washed with brine (10 ml), dried (Na ₂ SO ₄ ) and concentrated. The residue was purified by column chromatography (SiO2, petroleum ether/ethyl acetate, 5/1) to give tert-butyl 4-oxo-2-thia-8-azaspiro[4.5]decan-8-carboxylate (0.39 g, 1 .44 mmol, 44%) as a colorless oil. 1H NMR (400 MHz, Chloroform-d) δ 3.91 (m, 2H), 3.34 (s, 2H), 3.09-3.00 (m, 2H), 2.98 (s, 2H) , 1.82-1.73 (m, 2H), 1.63-1.54 (m, 2H), 1.46 (s, 9H).

Stage 7. Synthesis of tert-butyl-4-oxo-2-thia-8-azaspiro[4.5]decane-8-carboxylate-2,2-dioxide.

To a solution of tert-butyl 4-oxo-2-thia-8-azaspiro[4.5]decane-8-carboxylate (0.39 g, 1.44 mmol, 1 eq.) in DCM (30 mL) was added mCPBA in one portion (1.42 g, 5.75 mmol, 70% purity, 4 equiv.) at 0° C. under N2. The mixture was stirred at 20°C for 2 hours. The residue was poured into a saturated solution of Na ₂ S ₂ O ₃ (30 ml) and stirred for 10 minutes. The aqueous phase was extracted with DCM (2x50 ml). The combined organic phase was washed with brine (10 ml), dried (Na ₂ SO ₄ ), filtered and concentrated. The residue was purified by column chromatography (SiO2, petroleum ether/ethyl acetate, 5:1 to 1:1) to give tert-butyl 4-oxo-2-thia-8-azaspiro[4.5]decan-8-carboxylate 2,2 α-dioxide (0.27 g, 0.889 mmol, 61%) as a white solid. 1H NMR (400 MHz, Chloroform-d) δ 3.95 (m, 2H), 3.87 (s, 2H), 3.50 (s, 2H), 3.04 (m, 2H), 2.07 -1.97(m, 2H), 1.78(m, 2H), 1.47(s, 9H).

Step 8. Synthesis of tert-butyl-(S)-4-(((R)-tert-butylsulfinyl)amino)-2-thia-8-azaspiro[4.5]decane-8carboxylate-2,2-dioxide.

A solution of tert-butyl 4-oxo-2-thia-8-azaspiro[4.5]decane-8-carboxylate-2,2-dioxide (0.27 g, 0.890 mmol, 1.00 eq.), (R )-2-methylpropane-2-sulfinamide (215.73 mg, 1.78 mmol, 2.00 eq.) and titanium ethoxide (812 mg, 3.56 mmol, 4 eq.) in THF (65 ml) was stirred at 80°C for 15 hours After cooling to -4°C, MeOH (4.5 ml) was added, followed by the dropwise addition of LiBH ₄ (2 M, 445 μl, 1 eq.) and the resulting mixture was stirred for 1 hour at -4°C. The reaction mixture was poured into a saturated solution of NaHCO ₃ (30 ml) and the aqueous phase was extracted with ethyl acetate (3x100 ml). The combined organic phase was washed with brine (3x10 ml), dried (Na ₂ SO ₄ ), filtered and concentrated. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, from 5/1 to 0:1) to give tert-butyl-(S)-4-(((R)-tert-butylsulfinyl)amino)-2 -thia8-azaspiro[4.5]decane-8-carboxylate-2,2-dioxide (0.18 g, 0.440 mmol, 49%) as a white solid. 1H NMR (400 MHz, Chloroform-d) δ 4.06 (m, 1H), 3.95 (m, 1H), 3.75-3.58 (m, 1H), 3.52 (m, 1H) , 3.33 (m, 1H), 3.27-3.02 (m, 2H), 2.94-2.78 (m, 2H), 1.83-1.69 (m, 4H), 1 .47 (s, 9H), 1.28-1.24 (m, 9H).

Step 9. Synthesis of (R)-N-((S)-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-4-yl)-2-methylpropan-2sulfinamide.

To a solution of tert-butyl-(S)-4-(((R)-tert-butylsulfinyl)amino)-2-thia-8-azaspiro[4.5]decan-8carboxylate-2,2-dioxide (0.18 g, 0.440 mmol, 1 eq.) in DCM (3 ml) was added trifluoroacetic acid (2.51 g, 22.03 mmol, 1.63 ml, 50 eq.) in one portion and the resulting solution was stirred for 1 h at 20 °C The reaction solution was concentrated to give (R)-N-((S)-2,2dioxido-2-thia-8-azaspiro[4.5]decan-4-yl)-2-methylpropan-2-sulfinamide (0.2 g, 0.372 mmol, 84%, 2 TFA) as a light yellow oil. 1H NMR (400 MHz, MeOH-d ₄ ) δ 4.15-4.07 (m, 1H), 3.73-3.66 (m, 1H), 3.64-3.52 (m, 1H) , 3.49-3.36(m, 3H), 3.28-3.12(m, 3H), 3.10-2.96(m, 1H), 2.30(m, 1H), 2 .18-1.74 (m, 4H), 1.32-1.24 (m, 9H).

Step 10. Synthesis of ethyl 3-((S)-4-(((R)-tert-butylsulfinyl)amino)-2,2-dioxido-2-thia-8azaspiro[4.5]decan-8-yl)-6 -(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate.

To a solution of (R)-N-((S)-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-4-yl)-2-methylpropan-2-sulfinamide (0.2 g, 0.648 mmol, 1 eq.) and ethyl 3-chloro-6-(2,3-dichlorophenyl)-5-methylpyrazine-2-carboxylate (224 mg, 0.648 mmol, 1 eq.) in isopropyl alcohol (3 ml) DIPEA (419 mg, 3.24 mmol, 564 mL, 5 eq.) was added in one portion at 85° C. under N2 atmosphere. The mixture was concentrated in vacuo. The residue was purified by column chromatography (SiO ₂ , petroleum ether/ethyl acetate, 5/1 to 0:1) to give ethyl 3-((S)-4

- 216 041617 (((R)-tert-butylsulfinyl)amino)-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl)-5methylpyrazine -2-carboxylate (0.14 g, 0.226 mmol, 35%) as a white solid. 1H NMR (400

MHz, Chloroform-d) δ 7.55-7.49 (m, 1H), 7.32-7.28 (m, 2H), 4.43 (q, J=7.06 Hz, 2H), 4 .09-3.90(m, 3H), 3.713.63(m, 1H), 3.56(m, 1H), 3.38(m, 1H), 3.34-3.23(m, 2H ), 3.23-3.08 (m, 2H), 2.30 (s, 3H), 2.03-1.85 (m, 4H), 1.40 (t, J=7.06 Hz, 3H), 1.27(s, 9H).

Stage 11. Synthesis of ethyl-(S)-3-(4-amino-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5- methylpyrazine-2-carboxylate.

A mixture of ethyl 3-((S)-4-(((R)-tert-butylsulfinyl)amino)-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-8yl)-6-(2 ,3-Dichlorophenyl)-5-methylpyrazine-2-carboxylate (0.14 g, 0.226 mmol, 1 eq.) in HCl/MeOH (10 mL) was stirred at 20° C. for one hour. The reaction mixture was concentrated to give crude ethyl-(S)-3-(4-amino-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-8-yl)-6-(2,3-dichlorophenyl )5-methylpyrazine-2-carboxylate (0.12 g) as a white solid used directly in the next reaction. ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 7.65 (m, 1H), 7.46-7.40 (m, 1H), 7.38-7.33 (m, 1H), 4, 40 (q, J=7.06 Hz, 2H), 4.13-3.98 (m, 3H), 3.85-3.77 (m, 2), 3.67-3.60 (m, 1H), 3.56-3.50 (m, 1H), 3.42 (m 1H), 3.24 (m, 2H), 2.28 (s, 3H), 2.06-1.85 ( m, 4H), 1.41-1.34 (m, 3H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₂ H ₂₆ Cl ₂ N ₄ O ₄ S: 513.1; the found value is 513.0.

Step 12. Synthesis of (S)-4-amino-8-(5-(2,3-dichlorophenyl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-2thia-8-azaspiro[4.5]decan- 2,2-dioxide.

To a solution of ethyl-(S)-3-(4-amino-2,2-dioxido-2-thia-8-azaspiro[4.5]decan-8-yl)-6-(2,3dichlorophenyl)-5-methylpyrazin- 2-carboxylate (0.08 g, 0.155 mmol, 1 eq.) in THF (2 ml) LiAlH ₄ (2 M, 779.06 μl, 10 eq.) was added in one portion at 0°C under N ₂ atmosphere. The mixture was stirred at 0° C. for 0.1 h. MeOH (0.5 ml) was added dropwise to the reaction mixture, and the resulting solution was filtered and concentrated. The residue was purified by preparative HPLC to give (S)-4-amino-8-(5-(2,3-dichlorophenyl)-3-(hydroxymethyl)-6-methylpyrazin-2-yl)-2-thia-8azaspiro[ 4.5]decane-2,2-dioxide (4.7 mg, 0.01 mmol, 6.4%) as starting material. 1H NMR (400

MHz, MeOH-d4) δ 7.63 (m, 1H), 7.44-7.38 (m, 1H), 7.36-7.31 (m, 1H), 4.67 (s, 2H) , 3.83-3.71(m, 2H), 3.583.45(m, 3H), 3.22-3.03(m, 4H), 2.25(s, 3H), 2.15-2 .05 (m, 1H), 2.02-1.93 (m, 1H), 1.91-1.83 (m, 1H), 1.75 (m, 1H). LC-MS (ESI): mass/charge: [M+H] calc. for C ₂₀ H ₂₄ Cl ₂ N ₄ O ₃ S: 471.1; the found value is 471.1.

Example 307 6-(4-Amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)-5-(hydroxymethyl)-1,2dihydropyrazin-2-one.

Stage 1. Synthesis of 5-bromo-3-((4-methoxybenzyl)oxy)pyrazine-2-amine.

To a solution of 3,5-dibromopyrazine-2-amine (10 g, 39.54 mmol, 1 eq) and (4-methoxyphenyl) methanol (8.19 g, 59.31 mmol, 7.38 ml, 1.50 equiv.) in dioxane (100 ml) was added KOt-Bu (6.66 g, 59.31 mmol, 1.50 equiv.) at 25°C. The mixture was stirred at 100°C for 2 h, after which it was cooled and quenched by adding water (30 ml). The product was extracted with EtOAc (3x30 ml). The combined organic layers were washed with brine (50 ml), dried (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give 5-bromo-3-((4-methoxybenzyl)oxy)pyrazine-2-amine (10 g, 32.24 mmol, 81%) as a yellow solid.

Stage 2. Synthesis of 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine.

t-BuONO (13 .30 g, 128.97 mmol, 15.29 ml, 4.00 eq.) and I ₂ (9.82 g, 38.69 mmol, 7.79 ml, 1.20 eq.), the mixture was stirred at 25 °C for 3 hours. The reaction mixture was diluted with an aqueous solution of Na ₂ S ₂ O ₃ (50 ml) and was extracted with DCM (3x50 ml). The combined organic layers were washed with brine (30 ml), dried over Na2SO4, filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine (8 g, 19.00 mmol, 58% yield) as a white solid. LC-MS (ESI): mass/charge [M+H] calc. for C ₁₂ H ₁₁ BrIN ₂ O ₂ : 420.9; the found value is 420.7.

- 217 041617

Stage 3. Synthesis of 5-bromo-2-(2,3-dichlorophenyl)-3-((4-methoxybenzyl)oxy)pyrazine.

To a solution of 5-bromo-2-iodo-3-((4-methoxybenzyl)oxy)pyrazine (8 g, 19.00 mmol, 1.00 eq.) and (2,3dichlorophenyl)boronic acid (3.63 g, 19.00 mmol, 1 eq.) in CH3CN (30.00 ml) and H ₂ O (3.00 ml) was added K ₃ PO ₄ (8.07 g, 38.00 mmol, 2.00 eq.) and Pd(dppf)Cl ₂ -DCM (155.17 mg, 0.190 mmol, 0.01 eq.) at 20°C. The mixture was stirred at 60° C. for 2 h under N2. The cooled reaction mixture was diluted with H ₂ O (10 ml) and was extracted with EtOAc (3x10 ml). The combined organic layers were washed with brine (30 ml), dried (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give 5-bromo-2-(2,3-dichlorophenyl)-3-((4-methoxybenzyl)oxy)pyrazine (3 g, 6.82 mmol, 35% yield) as a colorless oil .

Step 4. Synthesis of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-((4-methoxybenzyl)oxy)pyrazin-2-yl)-4methylpiperidin-4-yl)carbamate.

Two equivalent batches were prepared in parallel. To a solution of 5-bromo-2-(2,3-dichlorophenyl)-3((4-methoxybenzyl)oxy)pyrazine (1 g, 2.27 mmol, 1.00 eq.) and tert-butyl-N-(4 -methyl-4piperidyl)carbamate (633.00 mg, 2.95 mmol, 1.30 eq.) in toluene (15.00 ml) was added NaOt-Bu (436.70 mg, 4.54 mmol, 2.00 eq. .), BINAP (141.48 mg, 0.227 mmol, 0.10 eq.) and Pd ₂ (dba) ₃ (104.03 mg, 0.113 mmol, 0.05 eq.) at 20°C.

The mixture was stirred at 130° C. for 3 h with microwave heating under N ₂ atmosphere. The two reaction mixtures were cooled, combined and concentrated. The residue was purified by column chromatography to give tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-((4methoxybenzyl)oxy)pyrazin-2-yl)-4-methylpiperidin-4-yl)carbamate (1.2 g, 2.09 mmol, 46%) as a yellow oil.

Stage 5. Synthesis of tert-butyl-(1-(3-bromo-5-(2,3-dichlorophenyl)-6-((4-methoxybenzyl)oxy)pyrazin-2yl)-4-methylpiperidin-4-yl)carbamate .

To a solution of tert-butyl-(1-(5-(2,3-dichlorophenyl)-6-((4-methoxybenzyl)oxy)pyrazin-2-yl)-4methylpiperidin-4-yl)carbamate (1 g, 1, 74 mmol, 1 eq.) in DCM (10.00 ml) was added NBS (465.50 mg, 2.62 mmol, 1.50 eq.) at 0°C. The mixture was stirred at 0°C for 1 h after which the reaction mixture was quenched by adding saturated NaHSO3 solution (3 ml), diluted with H 2 O (5 ml) and extracted with DCM (3x10 ml). The combined organic layers were washed with brine (30 ml), dried (Na2SO4), filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give tert-butyl-(1-(3-bromo-5-(2,3-dichlorophenyl)-6-((4-methoxybenzyl)oxy)pyrazin-2-yl)-4-methylpiperidin-4yl )carbamate (0.5 g, 0.766 mmol, 44%) as a yellow oil.

Step 6. Synthesis of methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3dichlorophenyl)-5-[(4-methoxyphenyl)methoxy]pyrazine-2-carboxylate.

To a solution of tert-butyl N-[1-[3-bromo-5-(2,3-dichlorophenyl)-6-[(4-methoxyphenyl)methoxy]pyrazin-2yl]-4-methyl-4-piperidyl]carbamate (0.5 g, 0.766 mmol, 1.00 equiv.) in THF (5.00 ml) and MeOH (10.00 ml) was added Pd(dppf)Cl ₂ (56.08 mg, 0.076 mmol, 0. 10 eq.) and triethylamine (232.65 mg, 2.30 mmol, 319 µl, 3.00 eq.) at 20°C. The mixture was stirred at 80° C. for 2 hours under CO (50 psi), after which the reaction mixture was concentrated. The residue was purified by column chromatography to give methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3-dichlorophenyl)5-[(4-methoxyphenyl)methoxy]pyrazine -2-carboxylate (0.32 g, 0.506 mmol, 66%) as a yellow oil.

Step 7. Synthesis of methyl 3-(4-amino-4-methyl-1-piperidyl)-6-(2,3-dichlorophenyl)-5-hydroxypyrazine-2-carboxylate.

To a solution of methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3-dichlorophenyl)-5[(4-methoxyphenyl)methoxy]pyrazine-2-carboxylate (0 .32 g, 0.506 mmol, 1.00 eq.) in DCM (5.00 ml) was added TFA (123.19 g, 1.08 mol, 80.00 ml, 2132.37 eq.). The mixture was stirred at 25°C for 30 min, after which the reaction mixture was quenched by adding a saturated solution of Na2CO3 (1 ml) at 0°C. The residue was concentrated under reduced pressure, treated with DCM/MeOH (10 ml, 10:1) and filtered. The filtrate was concentrated to give methyl 3-(4-amino-4methyl-1-piperidyl)-6-(2,3-dichlorophenyl)-5-hydroxy-pyrazine-2-carboxylate (0.3 g, crude) as yellow oils. The residue was used in the next step without further purification. LC-MS (ESI): mass/charge [M+H] calc. for C ₁₈ H ₂₁ Cl ₂ N ₄ O ₃ : 411.1; the found value is 411.0.

Step 8 Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)-5-(hydroxymethyl)-1,2dihydropyrazin-2-one.

To a solution of methyl 3-(4-amino-4-methyl-1-piperidyl)-6-(2,3-dichlorophenyl)-5-hydroxy-pyrazine-2-carboxylate (0.1 g, 0.243 mmol, 1 eq.) in THF (5 ml) was added LAH (18.46 mg, 0.486 mmol, 2 eq.) at 0°C. The mixture was stirred at 0°C for 10 min, after which the reaction mixture was quenched by adding H ₂ O (1 ml) at 0°C. The resulting solution was filtered and concentrated under reduced pressure to give a residue. The residue was purified by preparative HPLC to give 6-(4-amino-4-methylpiperidin-1-yl)-3-(2,3-dichlorophenyl)-5-(hydroxymethyl)-1,2- 218 041617 dihydropyrazin-2- she (5 mg, 0.0131 mmol, 5.4%) as a white solid. 1H NMR (400 MHz,

Methanol-d4) δ 7.40-7.42 (d, J=7.45 Hz, 1H), 7.21-7.24 (m, 2H) 4.47 (s, 2H), 3.43- 3.46 (m, 2H), 3.13-3.21 (m,

2H), 1.75-1.87 (m, 4 H) 1.33 (s, 3H), LC-MS (ESI): mass/charge [M+H] calc. for C ₁₇ H ₂ iCl2N ₄ O2: 383.1;

the found value is 383.1.

Example 308 6-(4-Amino-4-methylpiperidin-1-yl)-3-[(2,3-dichlorophenyl)sulfanyl]-5(hydroxymethyl)-1,2-dihydropyrazin-2-one.

Stage 1. Synthesis of 5-bromo-2-(2,3-dichlorophenyl)sulfanyl-3-[(4-methoxyphenyl)methoxy]pyrazine.

To a solution of 5-bromo-2-iodo-3-[(4-methoxyphenyl)methoxy]pyrazine (2.68 g, 6.37 mmol, 1.00 eq., Example 307) and 2,3-dichlorobenzenethiol (1, 14 g, 6.37 mmol, 1.00 eq.) in dioxane (20.00 ml) was added CuI (121.23 mg, 0.636 mmol, 0.10 eq.), K ₃ PO ₄ (1.62 g, 7.64 mmol, 1.20 eq.) and 1,10-phenanthroline (114.7 mg, 0.636 mmol, 0.10 eq.). The resulting mixture was stirred at 70° C. for 3 hours. The cooled reaction mixture was then diluted with H ₂ O (10 ml) and extracted with EtOAc (3x10 ml). The combined organic layers were washed with brine (30 ml), dried (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give 5-bromo-2-(2,3-dichlorophenyl)sulfanyl-3[(4-methoxyphenyl)methoxy]pyrazine (2.20 g, 4.66 mmol, 73%) as white solid.

Step 2. Synthesis of tert-butyl N-[1-[5-(2,3-dichlorophenyl)sulfanyl-6-[(4methoxyphenyl)methoxy]pyrazin-2-yl]-4-methyl-4-piperidyl]carbamate.

To a solution of 5-bromo-2-(2,3-dichlorophenyl)sulfanyl-3-[(4-methoxyphenyl)methoxy]pyrazine (1.40 g, 2.96 mmol, 1.00 eq.) and tert-butyl- M-(4-methyl-4-piperidyl)carbamate (824.66 mg, 3.85 mmol, 1.30 eq.) in toluene (10.00 ml) mmol, 2.00 eq.), BINAP (184.3 mg, 0.296.00 mmol, 0.10 eq.) and Pd ₂ (dba) ₃ (135.53 mg, 0.148 mmol, 0.05 eq.) at 20°C. The mixture was stirred at 130° C. with microwave heating for 3 hours under N ₂ atmosphere. The residue was purified by column chromatography to give tert-butyl-M-[1-[5-(2,3-dichlorophenyl)sulfanyl-6[(4-methoxyphenyl)methoxy]pyrazin-2-yl]-4-methyl-4 -piperidyl]carbamate (500 mg, 0.825 mmol, 27%) as a yellow oil.

Stage 3. Synthesis of tert-butyl-M-[1-[3-bromo-5-(2,3-dichlorophenyl)sulfanyl-6-[(4methoxyphenyl)methoxy]pyrazin-2-yl]-4-methyl-4- piperidyl]carbamate.

To a solution of tert-butyl-M-[1-[5-(2,3-dichlorophenyl)sulfanyl-6-[(4-methoxyphenyl)methoxy]pyrazin2-yl]-4-methyl-4-piperidyl]carbamate (500, 00 mg, 0.825 mmol, 1.00 eq.) in DCM (10.00 ml) was added with NBS (220.4 mg, 1.24 mmol, 1.50 eq.) at 0°C. The reaction mixture was stirred at 0°C for 10 min and then extinguished by adding an aqueous solution of NaHSO ₃ (5 ml) at 0°C. The solution was diluted with H ₂ O (10 ml) and the product was extracted with DCM (3x10 ml). The combined organic layers were washed with brine (20 ml), dried (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to give a residue. The residue was purified by column chromatography to give t-butyl-M-[1-[3-bromo-5-(2,3-dichlorophenyl)sulfanyl-6-[(4methoxyphenyl)methoxy]pyrazin-2-yl]-4- methyl 4-piperidyl]carbamate (500 mg, 0.730 mmol, 88%) as a yellow oil.

Step 4. Synthesis of methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3dichlorophenyl)sulfanyl-5-[(4-methoxyphenyl)methoxy]pyrazine-2-carboxylate .

To a solution of tert-butyl-N1-[3-bromo-5-(2,3-dichlorophenyl)sulfanyl-6-[(4methoxyphenyl)methoxy]pyrazin-2-yl]-4-methyl-4-piperidyl]carbamate (500 mg, 0.730 mmol, 1.00 eq.) in MeOH (10.00 ml) and THF (10.00 ml) was added Pd(dppf)Cl ₂ (53.45 mg, 0.073 mmol, 0.10 eq.) and triethylamine (221.76 mg, 2.19 mmol, 304 µl, 3.00 eq.) at 20°C. The mixture was stirred at 70° C. for 2 hours under CO (50 psi) and the cooled reaction mixture was then concentrated. The residue was purified by column chromatography to give methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3-dichlorophenyl)sulfanyl-5-[(4methoxyphenyl)methoxy]pyrazine-2 -carboxylate (350 mg, 0.527 mmol, 72%) as a yellow oil.

Step 5. Synthesis of methyl 3-(4-amino-4-methylpiperidin-1-yl)-6-((2,3-dichlorophenyl)thio)-5hydroxypyrazine-2-carboxylate.

To a solution of methyl 3-[4-(tert-butoxycarbonylamino)-4-methyl-1-piperidyl]-6-(2,3dichlorophenyl)sulfanyl-5-[(4-methoxyphenyl)methoxy]pyrazine-2-carboxylate (0 .1 g, 0.151 mmol, 1.00 eq.) in DCM (3.00 ml) was added TFA (23.10 g, 202.58 mmol, 15.00 ml). The mixture was stirred at 25°C for

- 219 041617 for 0.5 h. The reaction mixture was concentrated under reduced pressure and adjusted to pH 7 with saturated Na2CO ₃ solution, then the mixture was concentrated to obtain methyl-3-(4-amino-4methylpiperidin-1-yl)-6-(( 2,3-dichlorophenyl)thio)-5-hydroxypyrazine-2-carboxylate (0.1 g, crude) as a yellow solid. LC-MS (ESI): mass/charge [M+H] calc. for C ₁₈ H ₂₁ Cl ₂ N ₄ O ₃ S:

443.1; the found value is 442.9.

Step 6 Synthesis of 6-(4-amino-4-methylpiperidin-1-yl)-3-[(2,3-dichlorophenyl)sulfanyl]-5(hydroxymethyl)-1,2-dihydropyrazin-2-one.

To a solution of methyl 3-(4-amino-4-methyl-1-piperidyl)-6-(2,3-dichlorophenyl)sulfanyl-5hydroxypyrazine-2-carboxylate (0.1 g, 0.225 mmol, 1.00 eq. ) in THF (5.00 mL) was added LiBH4 (9.83 mg, 0.451 mmol, 2.00 eq.) at 0°C. The mixture was stirred at 40°C for 1 h, then quenched by adding H ₂ O (1 ml) at 0°C. The solution was filtered and concentrated to give a residue. The residue was purified by preparative HPLC to give 6-(4-amino-4-methylpiperidin-1-yl)-3-[(2,3dichlorophenyl)sulfanyl]-5-(hydroxymethyl)-1,2-dihydropyrazin-2-one (2.5 mg, 0.006 mmol, 2.7% yield) as starting material. 1H NMR (400 MHz, methanol-d ₄ ) δ 7.27 (d, J=7.09 Hz, 1H), 7.05 (t, J=7.95 Hz, 1H), 6.94 (d, J=8.19Hz, 1H), 4.41(s, 2H), 3.52-3.55(m, 2H), 1.75-1.95(m, 4H), 1.39(s , 3H). LC-MS (ESI): mass/charge [M+H] calc. for C ₁₇ H ₂₁ Cl ₂ N ₄ O ₂ S: 415.1; the found value is 415.0.

Example 309 Synthesis of 3-({5-[(3S,4S)-4-amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6(hydroxymethyl)-3-methylpyrazine -2-yl}sulfanyl)-2-chloro-N,N-dimethylbenzamide.

3-({5-[(3S,4S)-4-Amino-3-methyl-2-oxa-8-azaspiro[4.5]decan-8-yl]-6-(hydroxymethyl)-3methylpyrazin-2-yl} sulfanyl)-2-chloro-N,N-dimethylbenzamide was synthesized by a method similar to the method in example 277, except that 4-bromo-3-chloro-2-((tetrahydro-2H-pyran-4-yl)oxy ) pyridine was replaced by 3-bromo-2-chloro-N,N-dimethylbenzamide. 1H NMR (500 MHz, Methanol^ ₄ ) δ 8.47 (s, 2H), 7.33 (t, J=7.7 Hz, 1H), 7.25 (dd, J=7.6, 1, 6 Hz, 1H), 7.21 (dd, J=7.8, 1.6 Hz, 1H), 4.57 (d, J=1.7 Hz, 2H), 4.30 (d, J= 6.7 Hz, 1H), 3.96 (d, J=9.1 Hz, 1H), 3.85 (d, J=9.1 Hz, 1H), 3.85 (d, J=32, 2, 13.1 Hz, 3H), 3.41 (d, J=4.1 Hz, 1H), 3.13 (s, 3H), 2.91 (s, 3H), 2.50 (s, 3H), 2.01-1.84 (m, 4H), 1.72 (d, J=12.9 Hz, 1H), 1.32 (d, J=6.5 Hz, 3H). LC-MS (ESI) mass/charge: [M+H] calc. for C ₂₄ H ₃₂ ClN ₅ O ₃ S: 506.19; the found value is 506.4. Synthesis of 3-bromo-2-chloro-N,N-dimethylbenzamide.

To a solution of 3-bromo-2-chlorobenzoic acid (200 mg, 849 µmol) in DMF (8.48 ml) was added dimethylamine hydrochloride (76.0 mg, 933 µmol), EDCI (193 mg, 1.01 mmol), HOBt (136 mg, 1.01 mmol) and DIPEA (367 µl, 2.12 mmol). The mixture was allowed to stir in a sealed vial at room temperature overnight. The resulting mixture was diluted with EtOAc and H ₂ O. The organic layer was separated and then washed three times with H ₂ O. The organic layer was dried over MgSO ₄ , filtered and concentrated under reduced pressure. The residue was purified by flash chromatography to give 3-bromo-2-chloro-N,N-dimethylbenzamide (280 mg, 1.06 mmol, 63.2%). LCMS (ESI): mass/charge: [M+H] calc. for C ₉ H ₉ BrClNO: 261.96; the found value is 261.8.

Biological examples - analysis of allosteric inhibition of SHP2.

Without being limited by theory, SHP is allosterically activated by the binding of bistirosyl-phosphorylated peptides to its Src homologous 2 (SH2) domains. The last activation step results in the release of the autoinhibitory surface of SHP2, which in turn makes the protein tyrosine phosphatase (PTP) SHP2 active and available for substrate recognition and reaction catalysis. SHP2 catalytic activity was monitored using a DiFMUP surrogate substrate in a fast fluorescence assay format.

Phosphatase reactions were performed at room temperature in a 96-well flat-bottom black polystyrene plate with a non-binding surface (Corning, cat. no. 3650) using a final reaction volume of 100 µl and the following assay conditions in buffer: 50 mM HEPES, pH 7.2 , 100 mM NaCl, 0.5 mM EDTA, 0.05% P-20, 1 mM DTT.

Monitoring of SHP2 inhibition by the compounds of the present invention (with concentrations ranging from 0.00005-10 μM) was performed using an assay in which 0.2 nM SHP2 was incubated with 0.5 μM activating peptide 1 (sequence: H ₂ NLN(pY )IDLDLV(dPEG8)LST(pY)ASINFQK-amide) or activating peptide 2 (sequence:

- 220 041617

H2N-LN(pY)AQLWHA(dPEG8)LTI(pY)ATIRRF-aMug). After incubation for 30-60 min at 25°C, DiFMUP surrogate substrate (Invitrogen, Cat # D6567) was added to the reaction mixture and activity was determined by kinetic reading using a microplate reader (Envision, Perkin-Elmer or Spectramax M5, Molecular Devices) . The excitation and emission wavelengths were 340 and 450 nM, respectively. Baseline values were determined from a linear fit of the data, and inhibitor dose-response curves were analyzed using a normalized IC ₅₀ regression curve fit with control-based normalization.

Inhibition of SHP2 by some compounds using the above protocol is shown in table. 13.

Table 13 Inhibition of SHP2 by Test Compounds

Compound IC ₅₀ SHP2, nM Compound 10 (example 1) 83 Compound 31 (Example 23) 43 Compound 32 (example 24) 104 Compound A-228 (example 228) 16

In some embodiments, the compounds of the present invention tested in the assay described above exhibit an activity of less than 1000 nM. In some embodiments, the compounds of the present invention tested in the assay described above exhibit an activity of about 10 to about 100 nM. In some embodiments, the compounds of the present invention tested in the assay described above exhibit an activity ranging from 10 to 100 nM. In some embodiments, the compounds of the present invention tested in the assay described above exhibit an activity of less than 10 nM.

Equivalents.

While the present invention has been described in conjunction with the specific embodiments set forth above, many alternatives, modifications, and other variations will be apparent to those of ordinary skill in the art. All such alternatives, modifications and variations are intended to be within the spirit and scope of the present invention.

Claims (28)

CLAIM 1. Compound of formula I-W ^{R2 R4} I-W G or its pharmaceutically acceptable salt or stereoisomer, where: A represents heterocycloalkyl, aryl or heteroaryl, while heterocycloalkyl, aryl and heteroaryl are 5-12-membered monocyclic or polycyclic, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from the group consisting of N, S, P and O; Y ¹ is -S-, direct bond, -NH-, -S(O) ₂ -, S(O) ₂ -NH- or -C(=CH ₂ )-; Y ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ; R ¹ is independently in each occurrence -H, -C1-C6-alkyl, -OR ⁶ , halogen, -CN, -NR5R ⁶ , -S(O)2R ⁵ , -C(O)NR ⁵ R ⁶ , - NR ⁵ C(O)R ⁶ , 5-12 membered monocyclic or polycyclic heterocyclyl, spiroheterocyclyl, heteroaryl or oxo, wherein each alkyl, heterocyclyl, spiroheterocyclyl or heteroaryl is optionally substituted with one or more of -OH, -CN or -S( O) ₂ R ⁵ , where heterocyclyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and spiroheterocycle contains one or more heteroatoms selected from N, S, P and O; R ² is independently -OH, -CN, -C ₁ -C ₆ -alkyl, -C ₂ -C ₆ -alkenyl or -C ₃ -C ₈ -cycloalkyl; wherein each alkyl, alkenyl, cycloalkyl is optionally substituted with one or more of —OH or halogen; R ^a is independently at each occurrence -H; - 221 041617 R ^b represents independently in each case -H, -C ₁ -C ₆ -alkyl, -C3-C ₈ -cycloalkyl or heterocyclyl, and heterocyclyl is 5-12-membered monocyclic or 5-12-membered polycyclic containing 1-5 heteroatoms selected from the group consisting of N, S, P and O; wherein each alkyl, cycloalkyl or heterocycle is optionally substituted with one or more of -NR5R ⁶ , -(CH ₂ ) _n OH or -CF3; R3 is independently -C ₁ -C ₆ alkyl, 3-12 membered polycyclic heterocycle, 5-12 membered spiro heterocycle, C ₃ -C ₈ cycloalkyl, or -(CH2) _n -R ^b , wherein each alkyl, spiro heterocycle, the heterocycle or cycloalkyl is optionally substituted with one or more of -C ₁ -C ₆ -alkyl, -NH2, 512-membered heterocyclyl or spiroheterocyclyl, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from N, S, P and O; or R ³ can be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, with each heterocycle or spiro heterocycle optionally substituted with one or more of -C1-C6 alkyl, halogen, -OR ^b , -NH2, -NHR ^b , heteroaryl, heterocyclyl, -(CH2)nNH2, -(CH ₂ ) _n OH, -CONHR ^b or =O, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from N, S, P and O; R ⁴ is independently -H, -C1-C6-alkyl, -C1-C6-hydroxyalkyl, -C(O)OR ⁵ , -NH(CH2)nOH, -C(O)NH(CH2) _n OH, - C(O)R ^b , -NH ₂ , -OH, -CN or -C(O)NR ⁵ R ⁶ , each alkyl being optionally substituted with one or more of -OH or -OR ^b ; or R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, where the heterocycle is optionally substituted with oxo, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N , S, P and O; R ⁵ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O; R ⁶ is independently -H, -C1-C6 alkyl, -C3-C8 cycloalkyl, monocyclic 3-12 membered heterocycle, -OR ⁷ or -CF3, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N , S, P and O; R ⁷ and R ⁸ are independently at each occurrence -H; and n is independently at each occurrence 0, 1, 2, 3, 4, 5, or 6. 2. Compound of formula I R ⁴ I or a pharmaceutically acceptable salt or stereoisomer thereof, where: A represents 5-12-membered monocyclic or polycyclic heterocycloalkyl, aryl or heteroaryl, where heterocycloalkyl contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and heteroaryl contains one or more ring heteroatoms selected from N, S, P and O; Y ¹ is -S- or a direct link; Y ² is -NR ^a -; R ¹ is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -OH, halogen, -CN, -NR5R ⁶ or -S(O)R ⁵ ; R ² is independently -OH, -CN, -Cl-C ₆ -alkyl, -C 2 -C ₆ -alkenyl or -C ₃ -C ₈ -cycloalkyl; wherein each alkyl, alkenyl or cycloalkyl is optionally substituted with one or more of —OH or halogen; R ^a is independently at each occurrence -H; R ^b is independently in each occurrence -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl or 5-12 membered heterocyclyl containing 1-5 heteroatoms selected from the group consisting of N, S, R and O; wherein each alkyl, cycloalkyl or heterocycle is optionally substituted with one or more of —OH or —NR ⁵ R ⁶ ; R ³ is independently -C ₁ -C ₆ -alkyl or 3-12-membered polycyclic heterocycle, each alkyl or heterocycle is optionally substituted with one or more -NH ₂ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of from N, S, P and O; or R ³ may be combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, each heterocycle or spiro heterocycle being optionally substituted with -C ₁ -C ₆ -alkyl, -OH or -NH2, where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O, and the spiro heterocycle contains one or more heteroatoms selected from H, S, P and O; R ⁴ is independently -H, or -C ₁ -C ₆ -alkyl, with each alkyl optionally substituted with one or more -OH; or R ^a and R ⁴ together with the atom or atoms to which they are attached may be combined to form a polycyclic 3-12 membered heterocycle, wherein the heterocycle is optionally substituted with oxo, wherein the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O; R ⁵ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O; R ⁶ is independently -H, -C ₁ -C ₆ -alkyl, -C ₃ -C ₈ -cycloalkyl, monocyclic 3-12 membered heterocycle or -OR ⁷ where the heterocycle contains 1-5 heteroatoms selected from the group consisting of N, S, P and O; R ⁷ and R ⁸ are independently at each occurrence -H; and n is independently at each occurrence 0, 1, 2, 3, 4, 5, or 6. 3. The compound according to claim 1, where the compound is represented by formula I-W6: ^{R2 R4} I-W6 or a pharmaceutically acceptable salt or stereoisomer thereof, wherein: A is a 5-12-membered monocyclic or polycyclic heteroaryl; Y ¹ is -S-; Y ² is -NR ^a -; wherein the bond on the left side of Y ² as shown is a bond to the pyrazine ring, and the bond on the right side of the Y ² moiety as shown is a bond to R ³ ; R ³ is combined with R ^a to form a 3-12 membered monocyclic or polycyclic heterocycle or a 5-12 membered spiro heterocycle, with each heterocycle or spiro heterocycle optionally substituted with one or more of -C ₁ -C ₆ -alkyl, -OH, - NH2, heteroaryl, heterocyclyl, -(CH2)nNH2 or -CONHRb; R ¹ is independently at each occurrence -H, -C ₁ -C ₆ -alkyl, -OH, halogen, -CN or -NR5R ⁶ ; R ² represents -C ₁ -C ₆ -alkyl; R ^b is independently at each occurrence -H or -C ₁ -C ₆ -alkyl; R ⁴ is -H, -C ₁ -C ₆ alkyl, -C ₁ -C ₆ hydroxyalkyl, -C(O)NH(CH2) _n OH, -C(O)R ^b , -C(O) NR ⁵ R ⁶ , -OH or -CN, wherein alkyl is optionally substituted with one or more -OH; or each R ⁵ and R ⁶ independently at each occurrence are -H or -C ₁ -C ₆ -alkyl; and n is independently at each occurrence 1, 2, 3, 4, 5, or 6. 4. A compound according to any one of claims 1 to 2, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ¹ is -S-. 5. The compound according to claim 1, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ¹ is a direct bond, -NH- or Y ¹ is -S(O) ₂ -, -S(O)2NH- or -C( = CH) ₂ -. 6. A compound according to any one of claims 1-2 or 4-5, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein Y ² is -(NR ^a )-. 7. A compound according to claim 6, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ is -C ₁ -C ₆ alkyl which is optionally substituted with one or more of -NH 2 , heterocyclyl, or spiroheterocyclyl. 8. A compound according to claim 6, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a, together with the atoms to which they are attached, are combined to form a 5-12 membered spiro heterocycle which is optionally substituted with -C ₁ -C ₆ - alkyl, -OH or -NH2. 9. The compound of claim 8, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the 5-12 membered spiro heterocycle contains piperidinyl. 10. A compound according to claim 9, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the 5-12 membered spiro heterocycle contains oxygen. 11. A compound according to claim 6, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a, together with the atoms to which they are attached, are combined to form a 3-12 membered monocyclic heterocycle which is optionally substituted with -C ₁ -C ₆ -alkyl, -OH, -NH2, heteroaryl, heterocyclyl, -(CH ₂ ) _n NH ₂ or -CONHR ^b . 12. The compound according to claim 6 or its pharmaceutically acceptable salt or stereoisomer, where R ^a and R ⁴ - 223 041617 together with the atom to which they are attached are combined to form a polycyclic 3-12 membered heterocycle. 13. A compound according to any one of claims 1-2 or 4-5, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R ³ and R ^a , together with the atoms to which they are attached, are combined to form a 3-12 membered polycyclic heterocycle which is optionally substituted -NH2. 14. A compound according to any one of claims 1-2 or 4-13, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein A is heterocycloalkyl or aryl. 15. The connection according to any one of paragraphs. 1-2 or 4-13 or a pharmaceutically acceptable salt or stereoisomer thereof, wherein A is heteroaryl. 16. A compound or a pharmaceutically acceptable salt or stereoisomer thereof selected from the group consisting of: - 224 041617 Me 17. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, selected from the group consisting of: - 225 041617 - 226 041617 - 227 041617 - 228 041617 - 229 041617 - 230 041617 - 231 041617 - 232 041617 - 233 041617 - 234 041617 18. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, selected from the group consisting of: - 235 041617 - 236 041617 A-160 Oh J Chu A-161 O ¹ / /” ^g 5 A-162 A-163 ² -m * L Jrt a A-164 'deg A-165 o - ^x s <4/ d A-166 •Uu A-167 urs A-168VA ⁴ *J Q> A-169 A-170 O O-d 4 A-171 usu A-172 'A. usu F' A-173 At /7“( About θ-th and - 237 041617 - 238 041617 - 239 041617 - 240 041617 - 241 041617 A-230 \u003d 7 p P? /=(_ O A-231 ii Ί 1 “ III i ^{1 Cl} VNH to Qy. A-232 s A A-233 J7 A-234 / z 2--ί ° S A-235 z zz O“ ^e 7— 7 A-236 Cl Οχι J Qy A-237 At »A^ -ί kC^.. A-238 A-239 3 2 A-240 :.- X A-241 <73ψ. - 242 041617 - 243 041617 - 244 041617 - 245 041617 - 246 041617 19. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, selected from the group consisting of: - 247 041617 20. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the compound is o / (A170) 21. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the compound is - 248 041617 22. A compound, or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the compound is (A266). 23. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the compound is OH (A283). 24. A compound or a pharmaceutically acceptable salt or stereoisomer thereof, wherein the compound is 25. A pharmaceutical composition that inhibits SHP2 activity, comprising a compound according to any one of pi. 1-24 or a pharmaceutically acceptable salt or stereoisomer thereof and a pharmaceutically acceptable carrier. 26. A method of treating a disease associated with SHP2 modulation in a subject in need thereof, comprising administering to the subject an effective amount of a compound of any one of pi. 1-24 or a pharmaceutically acceptable salt or stereoisomer thereof. 27. The method of claim 26, wherein the disease is selected from Noonan syndrome, Leopard syndrome, juvenile myelomonocytic leukemia, neuroblastoma, melanoma, acute myeloid leukemia, and breast, lung, and rectal cancers. 28. A method of treating a disease associated with SHP2 modulation in a subject in need thereof, comprising administering to the subject an effective amount of the pharmaceutical composition of claim 25.