TW202421151A - Wee1 inhibitors and methods for treating cancer - Google Patents

Abstract

Compounds of general Formula (I) are provided herein. Such compounds, as well as pharmaceutically acceptable salts and compositions thereof, are useful for treating diseases or conditions, including conditions characterized by excessive cellular proliferation, such as breast cancer.

Description

WEE1 inhibitors and methods for treating cancer

The present application generally relates to compounds that are WEE1 inhibitors and/or degraders thereof, and methods of using the same for treating conditions characterized by excessive cell proliferation, such as cancer.

DNA is constantly damaged by the environment. Light, chemicals, stress, and cell replication cause single or double strand breaks along the DNA backbone. In general, organisms resist DNA damage by using repair proteins that reattach or resynthesize damaged DNA. The correct functioning of these proteins is essential for life. Incorrect substitutions of nucleotides into DNA can cause mutations (and other genetic changes, including but not limited to insertions, deletions, and frameshifts), genetic diseases, and loss of protein function. Complete loss of DNA repair can cause cell death, tumor progression, and cancer.

Cell cycle checkpoints are important for proper DNA repair, ensuring that cells do not undergo cell replication until their genomic integrity is restored. WEE1 is a nuclear kinase that participates in the G2-M cell cycle checkpoint arrest for DNA repair prior to entering mitosis. Normal cells repair damaged DNA during the G1 arrest. Cancer cells often have a defective G1-S checkpoint and rely on a functional G2-M checkpoint for DNA repair. WEE1 is overexpressed in various cancer types.

Various inhibitors and/or degraders of WEE1 are known to those of ordinary skill in the art. See, for example, WO 2019/173082 and WO 2020/069105. However, there is still a pressing need for inhibitors and/or degraders of WEE1 that can be used to treat conditions characterized by excessive cell proliferation, such as cancer.

Various embodiments provide a compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein the compound has the following structure: (I) wherein: ^R1 may be absent, substituted or unsubstituted 6- to 10-membered aryl, -NH-(substituted or unsubstituted 6- to 10-membered aryl)-, substituted or unsubstituted 5- to 10-membered heteroaryl, -NH-(substituted or unsubstituted 5- to 10-membered heteroaryl)-, or -NH-(substituted or unsubstituted 6- to 10-membered cycloalkyl)-; ^R2 may be absent, substituted or unsubstituted 4- to 10-membered heterocyclo, or -O-(substituted or unsubstituted 4- to 10-membered heterocyclo); ^R3 may be absent, substituted or unsubstituted _C1 - _C6 alkylene, -NH-, -NH-(substituted or unsubstituted _C1 - _C6 alkylene)-, -O-(substituted or unsubstituted _C1 -C6 alkylene)- R ⁴ may be absent or a substituted or unsubstituted _{4- to 10} -membered heterocyclic group ^{; provided that at least two of R 1 , R 2} _, ^R ₃ ^, and R ⁴ are present; R ^C may be or ; ^RD may be substituted or unsubstituted _C1 - _C6 alkyl; and Y is -CH or N (nitrogen).

Another embodiment provides a compound or a pharmaceutically acceptable salt thereof, wherein the compound may have a structure selected from Compound Nos. 1 to 18 as described herein.

Another embodiment provides a pharmaceutical composition, which may include an effective amount of a compound of formula (I) as described herein or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, diluent, excipient, or a combination thereof.

Another embodiment provides a use of an effective amount of a compound of formula (I) as described herein or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that may include such a compound as described herein, in the manufacture of a medicament for improving or treating cancer, wherein the cancer may be selected from brain cancer, cervicocerebral cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer, ovarian cancer, choriocarcinoma, uterine cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, cancer), skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Ewing's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma.

Another embodiment provides a use of an effective amount of a compound of formula (I) as described herein or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that may include such a compound as described above, in the manufacture of a medicament for inhibiting malignant growth or tumor replication, wherein the malignant growth or the tumor may be caused by a cancer selected from the following: brain cancer, cranial cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, Cancer, colorectal cancer, ovarian cancer, choriocarcinoma, corpus uteri cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Evan's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma.

Another embodiment provides a use of an effective amount of a compound of formula (I) as described herein, or a pharmaceutical composition that may include such a compound as described above, in the manufacture of a medicament for improving or treating malignant growth or tumor, wherein the malignant growth or the tumor may be caused by a cancer selected from the following: brain cancer, cranial cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer , ovarian cancer, choriocarcinoma, corpus carcinoma, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Evan's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma.

These and other embodiments are described in more detail below.

WEE1 is a tyrosine kinase that is a key component of ATR-mediated G2 cell cycle checkpoint control that prevents entry into mitosis in response to cellular DNA damage. ATR phosphorylates and activates CHK1, which in turn activates WEE1, leading to selective phosphorylation of cell cycle protein-dependent kinase 1 (CDK1) at Tyr15, thereby stabilizing the CDK1-cell cycle protein B complex and arresting cell cycle progression. This process confers a survival advantage to tumor cells by allowing time to repair damaged DNA before entering mitosis. Inhibition of WEE1 abolishes the G2 checkpoint, promoting cancer cells with DNA damage to enter unplanned mitosis and undergo cell death via mitotic aberration. Therefore, WEE1 inhibition and/or degradation has the potential to sensitize tumors to DNA-damaging agents such as cis-platinum and induce tumor cell death. Definition

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those of ordinary skill in the art. Unless otherwise specified, the entire text of all patents, applications, published applications, and other publications cited herein are incorporated herein by reference. If a term in this article has multiple definitions, the definition in this section shall prevail unless otherwise specified.

Whenever a group is described as "optionally substituted," the group may be unsubstituted or substituted with one or more of the indicated substituents. Likewise, when a group is described as "unsubstituted or substituted," if substituted, the substituent(s) may be selected from one or more of the indicated substituents. If no substituents are indicated, it means that the indicated "optionally substituted" or "substituted" group may be substituted with one or more groups individually and independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, aryl(alkyl), cycloalkyl(alkyl), heteroaryl(alkyl), heterocyclo(alkyl), hydroxy, alkoxy, acyl, cyano, halogen, thiocarbonyl, O-aminoformyl, N-aminoformyl, O-thiaminoformyl, N-thiaminoformyl, C-amido, N-amido, S-sulfonamido, N-sulfonamido, C-carboxyl, O-carboxyl, nitro, sulfenyl, sulfinyl, sulfonyl, halogenated alkyl, hydroxyalkyl, halogenated alkyloxy, amino, monosubstituted amino, disubstituted amino, and amine (C ₁ -C ₆ alkyl).

As used herein, "a" and "b" in " _Ca to _Cb " are integers referring to the number of carbon atoms in the group. The indicated group may contain "a" to "b" carbon atoms inclusively. Thus, " _C1 to _C4 alkyl" refers to all alkyl groups having 1 to 4 carbons, _i.e. , _{CH3- , CH3CH2- , CH3CH2CH2- , ( CH3} ) _{2CH- ,} CH3CH2CH2CH2- _{, CH3CH2CH} ( _CH3 )-, and ( _CH3 ) _3C- . If "a" and "b" are not specified, _the broadest range described in these definitions is assumed.

If two "R" groups are described as "taken together," the R groups and the atoms to which they are attached may form a cycloalkyl, cycloalkenyl, aryl, heteroaryl, or heterocyclic ring. For example, but not limited to, if ^Ra and ^Rb of an NR ^a R ^b group are indicated as "taken together," it means that they are covalently bonded to each other to form a ring:

As used herein, the term "alkyl" refers to a fully saturated aliphatic hydrocarbon group. The alkyl portion may be branched or straight chain. Examples of branched chain alkyl groups include, but are not limited to, isopropyl, dibutyl, tertiary butyl, and the like. Examples of straight chain alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and the like. The alkyl group may have 1 to 30 carbon atoms (whenever a numerical range such as "1 to 30" appears herein, it refers to each integer in the given range; for example, "1 to 30 carbon atoms" means that the alkyl group may consist of 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., up to and including 30 carbon atoms, although this definition also covers the occurrence of the term "alkyl" without specifying a numerical range). The alkyl group may also be a medium size alkyl group having 1 to 12 carbon atoms. The alkyl group may also be a lower alkyl group having 1 to 6 carbon atoms. The alkyl group may be substituted or unsubstituted.

As used herein, the term "alkenyl" refers to a monovalent straight or branched chain group of two to twenty carbon atoms containing a carbon double bond(s), including but not limited to 1-propenyl, 2-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl, and the like. The alkenyl group may be unsubstituted or substituted.

As used herein, the term "alkynyl" refers to a monovalent straight or branched chain radical of two to twenty carbon atoms containing a carbon bond(s), including but not limited to 1-propynyl, 1-butynyl, 2-butynyl, and the like. Alkynyl groups may be unsubstituted or substituted.

As used herein, "cycloalkyl" refers to a fully saturated (no double or triple bonds) monocyclic or polycyclic hydrocarbon ring system. When composed of two or more rings, the rings can be connected together in a fused, bridged, or spiro manner. As used herein, the term "fused" refers to two rings that share two atoms and one bond. As used herein, the term "bridged cycloalkyl" refers to compounds in which the cycloalkyl contains one or more bonds connecting non-adjacent atoms. As used herein, the term "spiro" refers to two rings that share one atom and the two rings are not connected by a bridge. Cycloalkyl groups may contain 3 to 30 atoms in the ring(s), 3 to 20 atoms in the ring(s), 3 to 10 atoms in the ring(s), 3 to 8 atoms in the ring(s), or 3 to 6 atoms in the ring(s). Cycloalkyl groups may be unsubstituted or substituted. Examples of monocyclic alkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of fused cycloalkyl groups are decahydronaphthyl, dodecahydro-1H-benzene, and tetradecahydronaphthyl; examples of bridged cycloalkyl groups are bicyclo[1.1.1]pentyl, adamantanyl, and norbornanyl; and examples of spirocycloalkyl groups include spiro[3.3]heptane and spiro[4.5]decane.

As used herein, "cycloalkenyl" refers to a monocyclic or polycyclic hydrocarbon ring system containing one or more double bonds in at least one ring; however, if there is more than one double bond, the double bonds must not form a completely delocalized π-electron system throughout all rings (otherwise the group would be an "aryl" as defined herein). For example, a cycloalkenyl may contain 3 to 10 atoms in the ring(s), 3 to 8 atoms in the ring(s), or 3 to 6 atoms in the ring(s). When composed of two or more rings, the rings may be fused, bridged, or spiro-linked together. A cycloalkenyl may be unsubstituted or substituted.

As used herein, "carbocyclyl" refers to a non-aromatic monocyclic or polycyclic hydrocarbon ring system. When composed of two or more rings, the rings may be connected together in a fused, bridged, or spiro manner as described herein. Carbocyclyl may contain 3 to 30 atoms in the ring (s), 3 to 20 atoms in the ring (s), 3 to 10 atoms in the ring (s), 3 to 8 atoms in the ring (s), or 3 to 6 atoms in the ring (s). Carbocyclyl may be unsubstituted or substituted. Examples of carbocyclyl groups include, but are in no way limited to, cycloalkyl and cycloalkenyl groups as defined herein, as well as the non-aromatic portion of 1,2,3,4-tetrahydronaphthalene, 2,3-dihydro-1H-indene, 5,6,7,8-tetrahydroquinoline, and 6,7-dihydro-5H-cyclopenta[b]pyridine.

As used herein, "aryl" refers to a carbocyclic (all-carbon) monocyclic or polycyclic aromatic ring system (including fused ring systems in which two carbocyclic rings share a chemical bond) having a fully delocalized π-electron system in all rings. The number of carbon atoms in an aryl group may vary. For example, an aryl group may be a _C6 - _C14 aryl group, a _C6 - _C10 aryl group, or a _C6 aryl group. Examples of aryl groups include, but are not limited to, benzene, naphthalene, and azulene. An aryl group may be substituted or unsubstituted.

As used herein, "heteroaryl" refers to a monocyclic or polycyclic aromatic ring system (a ring system with a completely delocalized π-electron system) containing one or more heteroatoms (e.g., 1, 2, or 3 heteroatoms), i.e., elements other than carbon, including but not limited to nitrogen, oxygen, and sulfur. The number of atoms in the ring(s) of the heteroaryl group may vary. For example, a heteroaryl group can contain 4 to 14 atoms in the ring(s), 5 to 10 atoms in the ring(s), or 5 to 6 atoms in the ring(s), such as nine carbon atoms and one heteroatom; eight carbon atoms and two heteroatoms; seven carbon atoms and three heteroatoms; eight carbon atoms and one heteroatom; seven carbon atoms and two heteroatoms; six carbon atoms and three heteroatoms; five carbon atoms and four heteroatoms; five carbon atoms and one heteroatom; four carbon atoms and two heteroatoms; three carbon atoms and three heteroatoms; four carbon atoms and one heteroatom; three carbon atoms and two heteroatoms; or two carbon atoms and three heteroatoms. In addition, the term "heteroaryl" includes fused ring systems in which two rings (e.g., at least one aryl ring and at least one heteroaryl ring or at least two heteroaryl rings) share at least one chemical bond. Examples of heteroaryl rings include, but are not limited to, furan, furoxane, thiophene, benzothiophene, thiophene, , pyrrole, Azoles, benzo Azoles, 1,2,3- Oxadiazole, 1,2,4- oxadiazole, thiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, benzothiazole, imidazole, benzimidazole, indole, indazole, pyrazole, benzopyrazole, isothiophene Azoles, benzoiso Azoles, isothiazoles, triazoles, benzotriazoles, thiadiazoles, tetrazoles, pyridines, , pyrimidine, pyridine , purine, pteridine, quinoline, isoquinoline, quinazoline, quinolone Phosphine, Phosphine, and tri The heteroaryl group may be substituted or unsubstituted.

As used herein, "heterocyclyl" or "heteroalicyclyl" refers to three, four, five, six, seven, eight, nine, ten to up to 18-membered monocyclic, bicyclic, and tricyclic ring systems, wherein carbon atoms together with 1 to 5 heteroatoms constitute the ring system. The heterocyclic ring may optionally contain one or more unsaturated bonds positioned in this manner, however, a completely delocalized π-electron system does not occur in all rings. (Multiple) heteroatom(s) are elements other than carbon, including but not limited to oxygen, sulfur, and nitrogen. The heterocycle may further contain one or more carbonyl or thiocarbonyl functionalities so that the definition includes pendoxy systems and thio systems, such as lactamides, lactones, cyclic imides, cyclic sulfimides, and cyclic carbamates. When composed of two or more rings, the rings can be connected together in a fused, bridged, or spiro manner. As used herein, the term "fused" refers to two rings that share two atoms and one bond. As used herein, the term "bridged heterocyclyl" or "bridged heteroalicyclyl" refers to compounds in which the heterocyclyl or heteroalicyclic group contains one or more bonds connecting non-adjacent atoms. As used herein, the term "spiro" means that two rings share one atom and the two rings are not connected by a bridge. Heterocyclic and heteroalicyclic groups can contain 3 to 30 atoms in the ring(s), 3 to 20 atoms in the ring(s), 3 to 10 atoms in the ring(s), 3 to 8 atoms in the ring(s), 3 to 6 atoms in the ring(s). For example, five carbon atoms and one impurity atom; four carbon atoms and two impurity atoms; three carbon atoms and three impurity atoms; four carbon atoms and one impurity atom; three carbon atoms and two impurity atoms; two carbon atoms and three impurity atoms; one carbon atom and four impurity atoms; three carbon atoms and one impurity atom; or two carbon atoms and one impurity atom. In addition, any nitrogen in the heteroalicyclic ring may be quaternary ammonium. The heterocyclic or heteroalicyclic group may be unsubstituted or substituted. Examples of such "heterocyclyl" or "heteroalicyclyl" include, but are not limited to, 1,3-dioxin, 1,3-dioxane, Alkane, 1,4-di 1,2-dioxolane, 1,3-dioxolane, 1,4-dioxolane, 1,3-oxathiane, 1,4-oxathiin, 1,3-oxathiolane, 1,3-dithiole, 1,3-dithiolane, 1,4-oxathiin, tetrahydro-1,4-thiadiol 、2H-1,2- , cis-butylene diimide, succinimide, barbituric acid, thiobarbituric acid, dioxopyridine , hydantoin, dihydrouracil, tri Alkane, hexahydro-1,3,5-tri , imidazoline, imidazoline, isocyanate Oxazoline, Isopropylamine Azoles, Oxazoline, Azoles, Oxazolidinone, thiazoline, thiazolidine, Phosphine, oxygen , piperidine N-oxide, piperidine, piperidine , pyrrolidine, nitrogen (azepane), pyrrolidone, pyrrolidinedione, 4-piperidone, pyrazoline, pyrazolidine, 2-oxopyrrolidine, tetrahydropyran, 4H-pyran, tetrahydrothiopyran, thio Phosphine, sulfur Phosphine Sulfide, Sulfur phenoxy sulfone, and benzo-fused analogs thereof (e.g., benzimidazolidinone, tetrahydroquinoline, and/or 3,4-methylenedioxyphenyl). Examples of spiroheterocyclic groups include 2-azaspiro[3.3]heptane, 2-oxaspiro[3.3]heptane, 2-oxaspiro[3.3]heptane, 2-oxa-6-azaspiro[3.3]heptane, 2,6-diazaspiro[3.3]heptane, 2-oxaspiro[3.4]octane, and 2-azaspiro[3.4]octane.

As used herein, "aralkyl" and "aryl(alkyl)" refer to an aryl group connected as a substituent via a lower alkylene group. The lower alkylene group and the aryl group of the aralkyl group may be substituted or unsubstituted. Examples include, but are not limited to, benzyl, 2-phenylalkyl, 3-phenylalkyl, and naphthylalkyl.

As used herein, "heteroaralkyl" and "heteroaryl (alkyl)" refer to a heteroaryl group connected as a substituent via a lower alkylene group. The lower alkylene group and heteroaryl group of the heteroaralkyl group may be substituted or unsubstituted. Examples include, but are not limited to, 2-thienylalkyl, 3-thienylalkyl, furanylalkyl, thienylalkyl, pyrrolylalkyl, pyridylalkyl, isothiocyanate, thiocyanate, pyrrolylalkyl, pyridylalkyl, isothiocyanate, pyrrolylalkyl ... oxazolylalkyl, and imidazolylalkyl, and benzo-fused analogs thereof.

"Heteroalicyclyl(alkyl)" and "heterocyclyl(alkyl)" refer to a heterocyclic or alicyclic group connected as a substituent via a lower alkylene group. The lower alkylene group and the heterocyclic group of the (heteroalicyclyl)alkyl group may be substituted or unsubstituted. Examples include, but are not limited to, tetrahydro-2H-pyran-4-yl(methyl), piperidin-4-yl(ethyl), piperidin-4-yl(propyl), tetrahydro-2H-thiopyran-4-yl(methyl) and 1,3-thiazinan-4-yl(methyl).

As used herein, an "alkylene group" is a _-CH2 -tethering straight chain alkyl group that forms a bond to connect molecular fragments through its terminal carbon atom. Examples of alkylene groups may be represented herein by -( _CH2 ) _n- , where n is an integer in the range of 1 to 30. A "lower" alkylene group is an alkylene group containing 1 to 6 carbon atoms. Examples of lower alkylene groups include, but are not limited to, methylene ( _-CH2- ), ethylene ( _-CH2CH2- ), propylene ( _-CH2CH2CH2- ), and butylene ( _{-CH2CH2CH2CH2-} ). Alkylene groups may be _formed by replacing one or more hydrogen atoms of the alkylene group and/or by replacing one _or more hydrogen atoms _of the _{alkylene group} with _a cycloalkyl group (e.g. ) replaces two hydrogens on the same carbon.

As used herein, the term "hydroxy" refers to an -OH group.

As used herein, "alkoxy" refers to the formula -OR, where R is alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl) as defined herein. A non-limiting list of alkoxy is methoxy, ethoxy, n-propoxy, 1-methylethoxy(isopropoxy), n-butoxy, isobutoxy, di-butoxy, tertiary-butoxy, phenoxy, and benzyloxy. Alkoxy may be substituted or unsubstituted.

As used herein, "acyl" refers to hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, heterocyclic, aryl(alkyl), heteroaryl(alkyl), and heterocyclic(alkyl) connected as a substituent through a carbonyl group. Examples include formyl, acetyl, propionyl, benzyl, and acrylyl. Acyl groups may be substituted or unsubstituted.

“Cyano” refers to the “-CN” group.

As used herein, the term "halogen atom" or "halogen" refers to any radiostable atom in column 7 of the periodic table, such as fluorine, chlorine, bromine, and iodine.

"Thiocarbonyl" refers to a "-C(=S)R" group, wherein R is the same as defined for O-carboxyl. The thiocarbonyl group may be substituted or unsubstituted.

“O-carbamyl” refers to a “—OC( _═O )N( _RARB )” group, wherein _RA and _RB may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl). O-carbamyl may be substituted or unsubstituted.

"N-carbamyl" refers to a "ROC(=O)N( _RA )-" group, wherein R and _RA may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl). N-carbamyl may be substituted or unsubstituted.

"O-thiocarbamyl" refers to a "-OC(=S)-N( _{RARB )} " group, wherein _RA and _RB may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl). O-thiocarbamyl may be substituted or unsubstituted.

"N-thiocarbamyl" refers to a "ROC(=S)N( _RA )-" group, wherein R and _RA may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl). N-thiocarbamyl may be substituted or unsubstituted.

"C-amido" refers to a "-C(=O)N( _{RARB )} " radical, wherein _RA and _RB may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclic, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclic(alkyl). C-amido may be substituted or unsubstituted.

"N-amido" refers to a "RC(=O)N( _RA )-" group, wherein R and _RA may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclic, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclic(alkyl). N-amido may be substituted or unsubstituted.

“S- _sulfonamido ” refers to a “—SO ₂ N( _RARB )” radical, wherein _RA and _RB may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclic, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclic(alkyl). The S-sulfonamido may be substituted or unsubstituted.

“N-sulfonamido” refers to the radical “RSO ₂ N( _RA )-”, wherein R and _RA may independently be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclic, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclic(alkyl). The N-sulfonamido may be substituted or unsubstituted.

An "O-carboxy" group refers to a "RC(=O)O-" group, where R can be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl), as defined herein. The O-carboxy group can be substituted or unsubstituted.

The terms "ester" and "C-carboxy" refer to a "-C(=O)OR" group, where R may be the same as defined for O-carboxy. Esters and C-carboxy may be substituted or unsubstituted.

"Nitro" refers to the "-NO ₂ " group.

A "sulfenyl" group refers to a "-SR" group, where R can be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl). The sulfenyl group can be substituted or unsubstituted.

"Sulfinyl" refers to a "-S(=O)-R" group, wherein R may be the same as defined for sulfenyl. A sulfinyl group may be substituted or unsubstituted.

"Sulfonyl" refers to an "SO ₂ R" group, wherein R may be the same as defined for sulfenyl. A sulfonyl group may be substituted or unsubstituted.

As used herein, "haloalky" refers to an alkyl group in which one or more hydrogen atoms are replaced by a halogen (e.g., monohaloalky, dihaloalky, trihaloalky, and polyhaloalky). Such groups include, but are not limited to, chloromethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1-chloro-2-fluoromethyl, 2-fluoroisobutyl, and pentafluoroethyl. The haloalky group may be substituted or unsubstituted.

As used herein, "haloalkoxy" refers to an alkoxy group in which one or more hydrogen atoms are replaced by a halogen (e.g., monohaloalkoxy, dihaloalkoxy, and trihaloalkoxy). Such groups include, but are not limited to, chloromethoxy, fluoromethoxy, difluoromethoxy, trifluoromethoxy, 1-chloro-2-fluoromethoxy, and 2-fluoroisobutoxy. The haloalkoxy group may be substituted or unsubstituted.

As used herein, the term "amino" refers to a -NH ₂ group.

A "mono-substituted amine" group refers to a "-NHR _A " group, wherein _RA can be alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl), as defined herein. _RA can be substituted or unsubstituted. Examples of mono-substituted amine groups include, but are not limited to -NH(methyl), -NH(phenyl), and the like.

A "di-substituted amine" group refers to a "-NR _A R _B " group, wherein _RA and _RB may independently be alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclo, cycloalkyl(alkyl), aryl(alkyl), heteroaryl(alkyl), or heterocyclo(alkyl), as defined herein. _RA and _RB may independently be substituted or unsubstituted. Examples of di-substituted amine groups include, but are not limited to _, -N(methyl), -N(phenyl)(methyl), -N(ethyl)(methyl), and the like.

As used herein, an "amine(alkyl)" group refers to a -(alkylene)-NR'R" group, wherein R' and R" are independently hydrogen or alkyl, as defined herein. The amine(alkyl) group may be substituted or unsubstituted. Examples of amine(alkyl) groups include, but are not limited to, _-CH2NH (methyl ₎ , _-CH2NH (phenyl ₎ , _{-CH2CH2NH (} methyl), -CH2CH2NH(phenyl), -CH2N(methyl) ₂ , _{-CH2N(phenyl)(methyl), -NCH2 ( ethyl} )(methyl), -CH2CH2N ₍ methyl) ₂ , _{-CH2CH2N (} phenyl)(methyl), _-NCH2CH2 ( _{ethyl )} (methyl), and the like.

When the number of substituents is not specified (e.g., haloalkyl), one or more substituents may be present. For example, "haloalkyl" may include one or more halogens that are the same or different. As another example, "C _{1 -C 3} alkoxyphenyl" may include one or more alkoxy groups _that are the same or different and contain one, two, or three atoms.

As used herein, a radical indicates a species having a single unpaired electron, such that the species containing the radical can covalently bond to another species. Thus, in this context, a radical is not necessarily a free radical. Rather, a radical represents a specific portion of a larger molecule. The term "radical" can be used interchangeably with the term "group".

The term "pharmaceutically acceptable salt" refers to a salt of a compound that does not cause significant irritation to an organism to which it is administered and does not inactivate the biological activity and properties of the compound. In some embodiments, the salt is an acid addition salt of the compound. Pharmaceutical salts can be obtained by reacting the compound with an inorganic acid, such as a hydrohalide (e.g., hydrochloric acid or hydrobromic acid), sulfuric acid, nitric acid, and phosphoric acid (e.g., 2,3-dihydroxypropyl dihydrogen phosphate). Pharmaceutical salts can also be obtained by reacting the compounds with organic acids such as aliphatic or aromatic carboxylic acids or sulfonic acids, for example formic acid, acetic acid, succinic acid, lactic acid, malic acid, tartaric acid, citric acid, ascorbic acid, niacin, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, trifluoroacetic acid, benzoic acid, salicylic acid, 2-hydroxyglutaric acid or naphthalenesulfonic acid. Pharmaceutical salts can also be obtained by reacting the compound with a base to form a salt, such as ammonium salts, alkali metal salts (such as sodium salts, potassium salts, or lithium salts), alkali earth metal salts (such as calcium salts or magnesium salts), carbonates, bicarbonates, organic bases (such as dicyclohexylamine, N-methyl-D-reduced glucosamine, tris(hydroxymethyl)methylamine, C ₁ -C ₇ alkylamines, cyclohexylamine, triethanolamine, ethylenediamine), and salts with amino acids (such as arginine and lysine). With respect to compounds of formula (I), one of ordinary skill in the art understands that when a salt is formed by protonation of a nitrogen-based group (e.g., NH ₂ ), the nitrogen-based group may associate with a positive charge (e.g., NH ₂ may become NH ₃ ⁺ ), and the positive charge may be balanced by a negatively charged counter ion (e.g., Cl ⁻ ).

As used herein, the terms "WEE1 inhibition", "WEE1 inhibitor", and similar terms refer to inhibiting the activity or function of WEE1 tyrosine kinase, for example, by degrading WEE1 tyrosine kinase and/or reducing the activity of WEE1 tyrosine kinase by targeting phosphorylation of CDK1. A WEE1 inhibitor that acts by degrading WEE1 tyrosine kinase is referred to herein as a WEE1 degrader.

It is understood that in any compound described herein having one or more chiral centers, if the absolute stereochemistry is not explicitly indicated, each center can independently have the R-configuration, or the S-configuration, or a mixture thereof. Thus, the compounds provided herein can be image-isomerically pure, image-isomerically enriched racemic mixtures, non-image-isomerically pure, non-image-isomerically enriched, or stereoisomer mixtures. In addition, it is understood that in any compound described herein having one or more double bonds that produce geometric isomers (which can be defined as E or Z), each double bond can independently be E or Z or a mixture thereof. Similarly, it is understood that in any described compound, all tautomeric isomeric forms are also intended to be included.

It should be understood that when the compounds disclosed herein have unfilled valences, the valences should be filled with hydrogen or its isotopes, such as hydrogen-1 (protium) and hydrogen-2 (deuterium). The compounds described herein may also include all isotopes of atoms occurring in the intermediate or final compounds. Isotopes include atoms having the same atomic number but different mass numbers. For example, isotopes of hydrogen include tritium and deuterium.

It should be understood that the compounds described herein may be isotopically labeled. Substitution with isotopes such as deuterium may provide certain therapeutic advantages due to higher metabolic stability, such as increased half-life in vivo or reduced dosage requirements. Each chemical element represented in a compound structure may include any isotope of that element. For example, in a compound structure, a hydrogen atom may be explicitly disclosed or understood to be present in the compound. At any position of a compound where a hydrogen atom may be present, the hydrogen atom may be any isotope of hydrogen, including but not limited to hydrogen-1 (protium), hydrogen-2 (deuterium), and hydrogen-3 (tritium). Therefore, compounds referenced herein encompass all potential isotopic forms unless the context clearly indicates otherwise.

It should be understood that the methods and compositions described herein include crystalline forms (also known as polymorphs, which include different crystal stacking arrangements of the same element composition of the compound), amorphous phases, salts, solvents, and hydrates. In some embodiments, the compounds described herein exist in a solvent-bound form with a pharmaceutically acceptable solvent (such as water, ethanol, or the like). In other embodiments, the compounds described herein exist in a non-solvent-bound form. Solvents contain stoichiometric or non-stoichiometric amounts of solvents and can be formed during the crystallization process with pharmaceutically acceptable solvents (such as water, ethanol, or the like). Hydrates are formed when the solvent is water, and alcoholates are formed when the solvent is alcohol. In addition, the compounds provided herein can exist in non-solvent-bound forms as well as solvent-bound forms. In general, solvent-incorporated forms are considered equivalent to non-solvent-incorporated forms for the purposes of the compounds and methods provided herein.

When a range of values is provided, it should be understood that the upper and lower limits of the range and each intervening value between the upper and lower limits are included in the embodiments.

Unless expressly stated otherwise, the terms, phrases, and variations thereof used in this application (especially in the appended claims) should be understood as open-ended and non-restrictive. As an example of the foregoing, the term "including" should be interpreted as meaning "including, without limitation/including but not limited to" or the like; as used herein, the term "comprising" is synonymous with "including," "containing," or "characterized by," and is inclusive or open-ended and does not exclude additional, unlisted elements or method steps; the term "having" should be interpreted as "having at least"; the term "include" should be interpreted as "includes but is not limited to"; to); the term “example” is used to provide illustrative examples of the items discussed rather than an exhaustive or limiting list thereof; and the use of terms such as “preferably,” “preferred,” or “desired/desirable,” and words of similar meaning should not be understood to imply that certain features are critical, necessary, or even important to structure or function, but are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment. In addition, the term “comprising” should be interpreted synonymously with the phrases “having at least” or “including at least.” When used in the context of a compound, composition, or device, the term "comprising" means that the compound, composition, or device includes at least the recited features or components, but may also include additional features or components.

With respect to the use of substantially any plural and/or singular terms herein, a person of ordinary skill in the art may translate from the plural to the singular and/or from the singular to the plural as appropriate to the context and/or application. Various singular/plural permutations may be expressly stated herein for clarity. The indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are listed in mutually different clauses does not indicate that a combination of these measures cannot be used to advantage. Any element symbol in the scope of the patent application should not be interpreted as limiting the scope. Compounds

Some embodiments disclosed herein relate to a compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein the compound has the following structure: (I) wherein R ¹ , R ² , R ³ , R ⁴ , ^RC , and ^RD are as described below.

In various embodiments, R ¹ in formula (I) may be absent, substituted or unsubstituted 6- to 10-membered aryl, -NH-(substituted or unsubstituted 6- to 10-membered aryl)-, substituted or unsubstituted 5- to 10-membered heteroaryl, -NH-(substituted or unsubstituted 5- to 10-membered heteroaryl)-, or -NH-(substituted or unsubstituted 6- to 10-membered cycloalkyl)-. In one embodiment, R ¹ may be absent. In another embodiment, R ¹ may be substituted or unsubstituted 6- to 10-membered aryl. For example, in this embodiment, R ¹ may be unsubstituted phenyl. In another embodiment, R ¹ may be -NH-(substituted or unsubstituted 6- to 10-membered aryl)-. For example, in this embodiment, R ¹ may be or In another embodiment, R ¹ can be a substituted or unsubstituted 5- to 10-membered heteroaryl. In another embodiment, R ¹ can be -NH-(substituted or unsubstituted 5- to 10-membered heteroaryl)-. In another embodiment, R ¹ can be -NH-(substituted or unsubstituted 6- to 10-membered cycloalkyl)-. For example, in this embodiment, R ¹ can be .

In various embodiments, ^R2 in formula (I) may be absent, a substituted or unsubstituted 4- to 10-membered heterocyclic group, or -O-(substituted or unsubstituted 4- to 10-membered heterocyclic group)-. In one embodiment, ^R2 may be absent. In another embodiment, ^R2 may be a substituted or unsubstituted 4- to 10-membered heterocyclic group. For example, in this embodiment, ^R2 may be , , ,or In another embodiment, ^R2 may be or In another embodiment, R ² may be -O-(substituted or unsubstituted 4- to 10-membered heterocyclic group)-. For example, in this embodiment, R ² may be .

In various embodiments, R ³ in formula (I) may be absent, substituted or unsubstituted C ₁ -C ₆ alkylene, -NH-, -NH-(substituted or unsubstituted C _{1 -C 6 alkylene)-, -O-(substituted or unsubstituted C 1 -C 6 alkylene )} -NH-, or -O-(substituted or unsubstituted C ₁ -C ₆ alkylene)-NH-(substituted or unsubstituted C ₁ -C ₆ alkylene)-. In one embodiment, R ³ may be absent. In another embodiment, R ³ may be substituted or unsubstituted C ₁ -C ₆ alkylene. For example, in this embodiment, R ³ may be -(CH ₂ )-, -(CH ₂ CH ₂ )-, or -(CH ₂ CH ₂ CH ₂ )-. In another embodiment, R ³ may be –(CH ₂ CHOH)–. In another embodiment, R ³ is –NH–. In another embodiment, R ³ may be –NH–(substituted or unsubstituted C ₁ -C ₆ alkylene)–. For example, in this embodiment, R ³ may be –NH–(CH ₂ )–. In another embodiment, R ³ may be –NH–(CH ₂ CH ₂ )–, –NH–(CH ₂ CH ₂ CH ₂ )–, or –NH–(CH ₂ CH ₂ CH ₂ CH ₂ )–. In another embodiment, R ³ may be –O–(substituted or unsubstituted C ₁ -C ₆ alkylene)–NH–. In another embodiment, R ³ may be –O–(CH ₂ ) ₄ –NH–. In another embodiment, R ³ may be -O-(substituted or unsubstituted C ₁ -C ₆ alkylene)-NH-(substituted or unsubstituted C ₁ -C ₆ alkylene)-. For example, in this embodiment, R ³ may be -O-(CH ₂ ) ₂ -NH-(CH ₂ )-.

In various embodiments, R ⁴ in formula (I) may be absent or substituted or unsubstituted 4 to 10-membered heterocyclic group. In one embodiment, R ⁴ may be absent. In another embodiment, R ⁴ may be an unsubstituted 4 to 10-membered heterocyclic group. For example, in this embodiment, R ⁴ may be or .

In various embodiments, at least two of R ¹ , R ² , R ³ , and R ⁴ in formula (I) are present. In some embodiments, at least three of R ¹ , R ² , R ³ , and R ⁴ are present. In some embodiments, all four of R ¹ , R ² , R ³ , and R ⁴ are present.

In various embodiments, R ^C in formula (I) may be or , wherein Y is -CH or N (nitrogen). In some embodiments, R ^C in formula (I) may be , and Y is -CH. In some embodiments, R ^C in formula (I) may be , and Y is N (nitrogen). In some embodiments, R ^C in formula (I) may be , and Y is -CH. In some embodiments, R ^C in formula (I) may be , and Y is N (nitrogen).

In various embodiments, ^RD can be a substituted or unsubstituted C ₁ -C ₆ alkyl. In various embodiments, ^RD can be a substituted C _{1 -C 6 alkyl. In various embodiments, RD can be an unsubstituted C 1 -C} ⁶ _alkyl . In various embodiments, ^RD can be a halogen-substituted C _{1 -C 6} alkyl. In various embodiments, ^RD can be an ethyl. In various embodiments, ^RD can be a methyl. In various embodiments, ^RD can be a halogen-substituted ethyl. In various embodiments, ^RD can be a halogen-substituted methyl.

Various embodiments provide a compound (e.g., a compound of formula (I)) or a pharmaceutically acceptable salt thereof, wherein the compound has a structure selected from the compounds Nos. 1 to 42 listed in Table A below: Table A Compound No. Structure 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , twenty one , twenty two , twenty three , 24A , 24B 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 and 42 , synthesis

The compounds of formula (I) or their pharmaceutically acceptable salts can be prepared in various ways by one of ordinary skill in the art using known techniques and guided by the detailed teachings provided herein, including the examples provided below. For example, in one embodiment, the compounds of formula (I) are prepared according to the general schemes depicted in Figures 1 to 52. Any preliminary reaction steps required to form the starting compounds or other precursors can be performed by one of ordinary skill in the art, for example by appropriately adjusting the reagents and conditions described in the examples. In Figures 1 to 52, the variables including ^R1 , ^R2 , ^R3 , ^R4 , ^RC , and ^RD can be as described elsewhere herein, and the synthetic transformations involved (as understood by one of ordinary skill in the art) are taken into account. As further illustrated in the examples below, R ⁵ , R ⁶ , R ⁷ , and R ⁸ are understood by those skilled in the art to be synthetic precursors of R ³ and R ^4. Pharmaceutical Compositions

Some embodiments described herein relate to a pharmaceutical composition, which may include an effective amount of one or more compounds described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) and a pharmaceutically acceptable carrier, diluent, excipient, or a combination thereof.

The term "pharmaceutical composition" refers to a mixture of one or more compounds and/or salts disclosed herein with other chemical components such as diluents or carriers. Pharmaceutical compositions facilitate administration of compounds to an organism. Pharmaceutical compositions can also be obtained by reacting a compound with an inorganic or organic acid such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, and salicylic acid. Pharmaceutical compositions are usually designed for a specific intended route of administration.

The term "physiologically acceptable" defines a carrier, diluent, or formulation that does not abrogate the biological activity and properties of the compound and does not cause significant injury or harm to the animal to which the composition is intended.

As used herein, "carrier" refers to a compound that facilitates the incorporation of a compound into cells or tissues. For example (but not limited to), dimethyl sulfoxide (DMSO) is a commonly used carrier that facilitates the incorporation of many organic compounds into cells or tissues of a subject.

As used herein, "diluent" refers to an ingredient in a pharmaceutical composition that lacks significant pharmacological activity but may be medically necessary or desirable. For example, a diluent can be used to increase the volume of an effective drug that is too small to be used for manufacturing and/or administration. It can also be a liquid used to dissolve a drug to be administered by injection, ingestion, or inhalation. A common form of diluent in the art is a buffered aqueous solution, such as, but not limited to, a phosphate-buffered saline solution that simulates the pH and isotonicity of human blood.

As used herein, "excipient" refers to a substantially inert substance that is added to a pharmaceutical composition to provide, but is not limited to, bulk, consistency, stability, binding ability, lubricity, disintegration ability, etc. to the composition. For example, stabilizers such as antioxidants and metal chelators are excipients. In one embodiment, the pharmaceutical composition comprises an antioxidant and/or a metal chelator. "Diluent" is a type of excipient.

The pharmaceutical compositions described herein can be administered to human patients by themselves, or can be administered to human patients in pharmaceutical compositions in which they are mixed with other active ingredients (such as in combination therapy), or carriers, diluents, excipients, or combinations thereof. The appropriate formulation depends on the route of administration chosen. The techniques for formulation and administration of the compounds described herein are known to those of ordinary skill in the art.

The pharmaceutical compositions disclosed herein can be manufactured in a manner known per se, for example by known mixing, dissolving, granulating, sugar-coated tablet manufacturing, grinding, emulsifying, encapsulating, encapsulating, or tableting procedures. In addition, the amount of active ingredient contained can effectively achieve its intended purpose. Many compounds used in the pharmaceutical combinations disclosed herein can be provided as salts containing pharmaceutically compatible relative ions.

There are many techniques for administering compounds, salts, and/or compositions in the art, including but not limited to oral, rectal, pulmonary, topical, aerosol, injection, infusion, and enteral delivery, including intramuscular, subcutaneous, intravenous, intramedullary, intrathecal, direct intraventricular, intraperitoneal, intranasal, and intraocular injection. In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof can be administered orally.

Compounds, salts, and/or compositions may also be administered in a local rather than systemic manner, for example by direct injection or implantation of the compound, typically in a storage or sustained release formulation, into the area of infection. Additionally, compounds may be administered by targeted drug delivery systems, such as liposomes coated with tissue-specific antibodies. The liposomes will be targeted to and selectively taken up by an organ. For example, intranasal or pulmonary delivery may be desired to target respiratory diseases or conditions.

If desired, the composition may be presented in a package or dispenser device which may contain one or more unit dosage forms (containing the active ingredient). The package may, for example, comprise metal or plastic foil, such as a blister pack. The package or dispenser device may be accompanied by instructions for administration. The package or dispenser may also be accompanied by a notice associated with the container regulating the manufacture, use, or sale of the drug, the notice being in a form prescribed by a governmental agency reflecting the agency's approval of the drug form for human or veterinary administration. For example, the notice may be a label or product leaflet approved by the U.S. Food and Drug Administration for prescription drugs. Compositions may also be prepared which may include the compounds and/or salts described herein formulated in a compatible pharmaceutical carrier, placed in an appropriate container and labeled for treatment of an indicated condition. Therapeutic uses and methods

Some embodiments described herein relate to a method for improving and/or treating a cancer described herein, which may include administering an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to a subject suffering from a cancer described herein. Other embodiments described herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) in the manufacture of a medicament for improving and/or treating a cancer described herein. Still other embodiments described herein relate to an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for improving and/or treating a cancer described herein.

Some embodiments described herein relate to a method for inhibiting the replication of a malignant growth or tumor, which may include contacting the growth or the tumor with an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof), wherein the malignant growth or the tumor is caused by a cancer described herein. Other embodiments described herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for the manufacture of a medicament for inhibiting malignant growth or replication of a tumor, wherein the malignant growth or the tumor is caused by a cancer described herein. Still other embodiments described herein relate to an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for inhibiting malignant growth or replication of a tumor, wherein the malignant growth or the tumor is caused by a cancer described herein.

Some embodiments described herein relate to a method for improving or treating a cancer described herein, which may include contacting a malignant growth or tumor of a subject suffering from a cancer described herein with an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof). Other embodiments described herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) in the manufacture of a medicament for improving or treating cancer, which may include contacting a malignant growth or tumor, wherein the malignant growth or the tumor is caused by a cancer described herein. Still other embodiments described herein relate to an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for ameliorating or treating cancer, which may include contacting a malignant growth or tumor, wherein the malignant growth or the tumor is caused by the cancer described herein.

Some embodiments described herein relate to a method for inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells), which may include providing an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to cancer cells from a cancer described herein. Other embodiments described herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) in the manufacture of a medicament for inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells). Still other embodiments described herein relate to an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells). Some embodiments described herein relate to a method for inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells), which may include providing an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to cancer cells from a cancer described herein. Other embodiments described herein relate to a method for inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells), which may include contacting cancer cells from a cancer described herein with an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to inhibit the activity of WEE1.

Some embodiments described herein relate to a method for improving or treating the cancer described herein, which may include using an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to inhibit the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells). Other embodiments described herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for the manufacture of a medicament for improving or treating a cancer described herein by inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells). Still other embodiments described herein relate to an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for improving or treating a cancer described herein by inhibiting the activity of WEE1 (e.g., inhibiting the activity of WEE1 in TP53 mutant cells, inhibiting the activity of WEE1 in TP53 wild-type cells, inhibiting the activity in WEE1 p53-deficient cells, and/or reducing the overexpression of WEE1 in cells). Some embodiments described herein relate to a method for ameliorating or treating a cancer described herein, comprising contacting a cancer cell with an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof), wherein the compound inhibits the activity of WEE1 (e.g., inhibits the activity of WEE1 in TP53 mutant cells, inhibits the activity of WEE1 in TP53 wild-type cells, inhibits the activity in WEE1 p53-deficient cells, and/or reduces the overexpression of WEE1 in cells).

Some embodiments disclosed herein relate to a method for inhibiting the activity of WEE1, which may include providing an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) to a subject having a cancer described herein or a cancer cell derived from a cancer described herein. Other embodiments disclosed herein relate to the use of an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) in the manufacture of a medicament for inhibiting the activity of WEE1. Still other embodiments disclosed herein relate to a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) for inhibiting the activity of WEE1.

Examples of suitable cancers include, but are not limited to, brain cancer, cranial cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer (e.g., non-small cell lung cancer and small cell lung cancer), stomach cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer, ovarian cancer, chorionic carcinoma, uterine cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, Prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Evan's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma.

As described herein, cancer can become resistant to one or more anticancer agents. In some embodiments, a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) or a pharmaceutical composition comprising an effective amount of a compound described herein (e.g., a compound of formula (I) or a pharmaceutically acceptable salt thereof) can be used to treat and/or ameliorate a cancer that has become resistant to one or more anticancer agents (e.g., one or more WEE1 inhibitors). Examples of anticancer agents to which a subject may have developed resistance include, but are not limited to, WEE1 inhibitors (e.g., AZD1775). In some embodiments, a cancer that has become resistant to one or more anticancer agents may be a cancer described herein.

Some known WEE1 inhibitors may cause one or more undesirable side effects in the treated subject. Examples of undesirable side effects include, but are not limited to, thrombocytopenia, neutropenia, anemia, diarrhea, vomiting, nausea, abdominal pain, and constipation. In some embodiments, the compounds described herein (e.g., compounds of Formula (I) or pharmaceutically acceptable salts thereof) can reduce the number and/or severity of one or more side effects associated with known WEE1 inhibitors. In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof may cause side effects (such as one of those described herein) that are more severe than those caused by known WEE1 inhibitors (such as AZD1775, formally known as MK1775 (CAS No.: 955365-80-7, 2-allyl-1-(6-(2-hydroxypropan-2-yl)pyridin-2-yl)-6-(4-(4-methylpiperidin-2-yl) ... In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof causes the number of side effects to be 25% less severe than the number of side effects experienced by a subject receiving a known WEE1 inhibitor (e.g., AZD1775). In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof causes the severity of a side effect (such as one of those described herein) to be reduced by about 10% to about 30% compared to the severity of the same side effect experienced by a subject receiving a known WEE1 inhibitor (such as AZD1775). In some embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof causes the number of side effects to be reduced by about 10% to about 30% compared to the number of side effects experienced by a subject receiving a known WEE1 inhibitor (eg, AZD1775).

In any of the embodiments described above under the heading "Compounds" there is provided one or more compounds of formula (I) or a pharmaceutically acceptable salt thereof, which are useful for treating, ameliorating, and/or inhibiting the growth of cancer in which inhibition of WEE1 activity is beneficial.

As used herein, "subject" refers to an animal that is the target of treatment, observation, or experiment. "Animal" includes cold-blooded and warm-blooded vertebrates and invertebrates, such as fish, crustaceans, reptiles, and particularly mammals. "Mammals" include, but are not limited to, mice, rats, rabbits, guinea pigs, dogs, cats, sheep, goats, cattle, horses, primates, such as monkeys, chimpanzees, and apes, and particularly humans. In some embodiments, the subject may be a human. In some embodiments, the subject may be a child and/or an infant, such as a child or infant with a fever. In other embodiments, the subject may be an adult.

As used herein, the terms "treat," "treating," "treatment," "therapeutic," and "therapy" do not necessarily imply a complete cure or elimination of a disease or condition. Any alleviation to any degree of any undesirable signs or symptoms of a disease or condition may be considered treatment and/or therapy. Additionally, treatment may include actions that may worsen a subject's overall sense of well-being or appearance.

The terms "therapeutically effective amount" and "effective amount" are used to indicate the amount of an active compound or pharmaceutical agent that elicits the indicated biological or pharmaceutical response. For example, a therapeutically effective amount of a compound, salt, or composition may be the amount required to prevent, alleviate, or ameliorate symptoms of a disease or condition, or prolong the survival of the subject being treated. This response may occur in a tissue, system, animal, or human, and includes the alleviation of signs or symptoms of the disease or condition being treated. In view of the disclosure provided herein, the determination of an effective amount is well within the capabilities of one of ordinary skill in the art. The therapeutically effective amount of the compounds disclosed herein required as dosage will depend on the route of administration, the type of animal (including humans) being treated, and the physical characteristics of the particular animal under consideration. Dosages may be adjusted to achieve the desired effect, but depend on factors such as body weight, diet, concomitant medications, and other factors that will be recognized by those of ordinary skill in the art of medicine.

For example, an effective amount of a compound or radiation is an amount that results in: (a) a reduction, alleviation, or disappearance of one or more symptoms caused by the cancer, (b) a reduction in tumor size, (c) tumor elimination, and/or (d) long-term disease stabilization (growth arrest) of the tumor. In the treatment of lung cancer (such as non-small cell lung cancer), a therapeutically effective amount is an amount that reduces or eliminates cough, shortness of breath, and/or pain. As another example, an effective amount or therapeutically effective amount of a WEE1 inhibitor and/or degrader is an amount that results in a reduction in WEE1 activity and/or phosphorylation (such as phosphorylation of CDC2). The reduction in WEE1 activity is known to those of ordinary skill in the art and can be determined by analyzing WEE1 intrinsic kinase activity and downstream substrate phosphorylation.

The amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof required for treatment will vary not only with the particular compound or salt selected, but also with the route of administration, the nature and/or symptoms of the disease or condition being treated, and the age and condition of the patient, and will ultimately be determined by the attending physician or clinician. In the case of administration of a pharmaceutically acceptable salt, the dosage may be calculated as a free base. One of ordinary skill in the art will appreciate that in certain circumstances, it may be necessary to administer the compounds disclosed herein in amounts exceeding or even far exceeding the dosage ranges described herein to effectively and aggressively treat particularly aggressive diseases or conditions.

However, in general, a suitable dosage will often be in the range of about 0.05 mg/kg to about 10 mg/kg. For example, a suitable dosage may be in the range of about 0.10 mg/kg to about 7.5 mg/kg body weight/day, such as about 0.15 mg/kg to about 5.0 mg/kg/recipient body weight/day, about 0.2 mg/kg to about 4.0 mg/kg/recipient body weight/day, or any amount therebetween. The compound may be administered in a unit dosage form; for example, each unit dosage form contains 1 to 500 mg, 10 to 100 mg, 5 to 50 mg, or any amount therebetween of active ingredient.

The desired dose may conveniently be presented in a single dose, or in divided doses administered at appropriate intervals, for example, as two, three, four, or more sub-doses per day. The sub-dose itself may be further divided, for example, into multiple discrete, loosely spaced doses.

As will be apparent to one of ordinary skill in the art, the useful in vivo dose and specific mode of administration to be administered will vary depending on the age, weight, severity of the ailment and species of mammal being treated, the specific compounds employed and the specific use for which these compounds are employed. Determination of effective dose levels (i.e., dose levels required to achieve the desired result) can be achieved by one of ordinary skill in the art using conventional methods, such as human clinical trials, in vivo studies, and in vitro studies. For example, the useful dose of a compound of formula (I) or a pharmaceutically acceptable salt thereof can be determined by comparing its in vitro activity with its in vivo activity in an animal model. This comparison can be made with established drugs such as cisplatin and/or gemcitabine.

Dosage and interval can be adjusted individually to provide plasma levels or minimum effective concentrations (MEC) of the active moiety sufficient to maintain the modulatory effect. The MEC will vary for each compound but can be estimated from in vivo and/or in vitro data. The dose required to achieve the MEC will depend on individual characteristics and the route of administration. However, plasma concentrations can be determined using HPLC assays or bioassays. Dose intervals can also be determined using MEC values. The composition should be administered using a regimen that maintains plasma levels above the MEC for 10 to 90% of the time, preferably between 30 and 90% of the time, and optimally between 50 and 90% of the time. In cases of local administration or selective absorption, the local effective concentration of the drug may be unrelated to plasma concentration.

It should be noted that the attending physician will understand how and when to terminate, interrupt, or adjust administration due to toxicity or organ dysfunction. Conversely, the attending physician will also know to adjust treatment to a higher level if the clinical response is inadequate (excluding toxicity). The amount of dosage administered when managing the condition of concern will vary with the severity of the disease or condition being treated and the route of administration. The severity of the disease or condition can be assessed, for example, in part based on standard prognostic assessment methods. In addition, the dosage and possible frequency of dosing will also vary based on the age, weight, and response of the individual patient. Plans similar to those discussed above can be used in veterinary medicine.

The compounds, salts, and compositions disclosed herein can be evaluated for efficacy and toxicity using known methods. For example, the toxicology of a particular compound or a subset of compounds that share certain chemical moieties can be established by determining toxicity in vitro on cell lines, such as mammalian (and preferably human) cell lines. The results of such studies are generally predictive of toxicity in animals (e.g., mammals) or more specifically, in humans. Alternatively, the toxicity of a particular compound in an animal model (e.g., mouse, rat, rabbit, dog, or monkey) can be determined using known methods. The efficacy of a particular compound can be established using several recognized methods, such as in vitro methods, animal models, or human clinical trials. When selecting a model to determine efficacy, one skilled in the art can be guided by current best practices in selecting an appropriate model, dose, route of administration, and/or regimen. Examples

Additional embodiments are further disclosed in detail in the following examples, which are not intended to limit the scope of the patent application in any way. Intermediate 1 3-((4-(4-(4-aminobenzyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione (Figure 4)

Step 1: At 0°C, add 3-(4-piperidin To a mixture of (4-methylphenyl)carbamic acid tributyl ester (132 mg, 596 µmol), NaBH(OAc) 3 (211 mg, 994 µmol), and DIEA (321 mg, 2.49 mmol) was added (4-methylphenyl)carbamate (132 mg, 596 µmol), NaBH(OAc) ₃ (211 mg, 994 µmol), and DIEA (321 mg, 2.49 mmol) in DCM (2 mL). The mixture was stirred at 20 °C under N ₂ for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was poured into H ₂ O (10 mL). The mixture was extracted with DCM (3 × 10 mL). The organic phase was washed with brine (10 mL), dried over anhydrous Na ₂ SO ₄ , filtered, and the filtrate was concentrated under reduced pressure to give a crude product. The crude product was purified by preparative TLC (MeOH:EA = 1:10, Rf = 0.5) to provide N- [4-[[4-[4-[(2,6-dioxo-3-piperidinyl)amino]phenyl]piperidinyl [-1-yl]methyl]phenyl]carbamic acid tributyl ester ( Boc protected intermediate 1 ) (0.120 g, 48% yield, 98% purity). LCMS (ESI ⁺ ) m/z 494.2 [M+H] ⁺ , RT: 0.481 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H, NH), 9.29 (s, 1H, NH), 7.39 (br d, J = 8.4 Hz, 2H), 7.18 (d, J = 8.4 Hz, 2H), 6.73 (d, J = 8.9 Hz, 2H), 6.60 (d, J = 8.9 Hz, 2H), 5.36 (br d, J = 7.1 Hz, 1H, NH), 4.23 - 4.14 (m, 1H), 3.41 (s, 2H), 2.90 - 2.97 (m, 4H), 2.75 - 2.65 (m, 1H), 2.63 - 2.53 (m, 1H), 2.50 - 2.43 (m, 4H), 2.16 - 2.04 (m, 1H), 1.80 - 1.65 (m, 1H), 1.47 (s, 9H).

Step 2: A mixture of Boc protected intermediate 1 (0.120 g, 238 µmol, 98% purity) in TFA (0.2 mL) and DCM (2 mL) was stirred at 20 °C under N ₂ for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was poured into NaHCO ₃ solution (10 mL). The mixture was extracted with DCM (3 × 10 mL). The organic phase was washed with brine (10 mL), dried over anhydrous Na ₂ SO ₄ , and filtered. The filtrate was concentrated under reduced pressure to give intermediate 1 , 3-[4-[4-[(4-aminophenyl)methyl]piperidin -1-yl]anilino]piperidine-2,6-dione (80 mg, 71% yield, 84% purity). LCMS (ESI ⁺ ) m/z 394.2 [M+H] ⁺ , RT: 0.688 min. Intermediate 2 3-((4-(4-(4-aminophenethyl)piperidin-2,6-dione) -1-yl)phenyl)amino)piperidin-2,6-dione (Figure 5)

Step 1: Boc protected intermediate 2 was prepared according to the procedure described in Step 1 of Intermediate 1 using tert-butyl (4-(2-oxoethyl)phenyl)carbamate instead of tert-butyl (4-formylphenyl)carbamate in 57% yield and 95% purity. LCMS (ESI ⁺ ) m/z 508.3 [M+H] ⁺ , RT: 0.554 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH), 9.21 (s, 1H, NH), 7.34 (br d, J = 8.4 Hz, 2H), 7.10 (d, J = 8.4 Hz, 2H), 6.75 (d, J = 8.9 Hz, 2H), 6.61 (d, J = 8.9 Hz, 2H), 5.37 (d, J = 7.3 Hz, 1H, NH), 4.19 (ddd, J = 11.2, 6.7, 4.9 Hz, 1H), 2.98 - 2.89 (m, 4H), 2.78 - 2.71 (m, 1H), 2.70 - 2.64 (m, 2H), 2.62 - 2.57 (m, 1H), 2.57 - 2.53 (m, 4H), 2.54 - 2.50 (m, 2H), 2.15 - 2.06 (m, 1H), 1.88 - 1.77 (m, 1H), 1.46 (s, 9H).

Step 2: Intermediate 2 was prepared according to the procedure described in Step 2 of Intermediate 1. Obtained in 73% isolation yield and 95% purity. LCMS (ESI ⁺ ) m/z 408.2 [MH] ⁺ , RT: 0.149 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.74 (s, 1H, NH), 6.87 (d, J = 8.3 Hz, 2H), 6.75 (d, J = 8.9 Hz, 2H), 6.61 (d, J = 8.9 Hz, 2H), 6.48 (d, J = 8.3 Hz, 2H), 5.36 (d, J = 7.3 Hz, 1H), 4.80 (br s, 2H), 4.19 (ddd, J =11.3, 7.0, 4.8 Hz, 1H), 2.99 - 2.88 (m, 4H), 2.78 - 2.68 (m, 1H), 2.62 - 2.56 (m, 8H), 2.47 - 2.44 (m, 1H), 2.15 - 2.07 (m, 1H), 1.89 - 1.77 (m, 1H). Intermediate 3 3-((4-(4-(4-aminophenyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione (Figure 6)

Step 1: At 20°C, 3-(4-piperidin To a solution of 3-[4-[(4-nitrophenyl)piperidine-2,6-dione (300 mg, 1.04 mmol) in DMF (6 mL) was added 1-fluoro-4-nitrobenzene (117 mg, 832 µmol) and DIEA (672 mg, 5.20 mmol). The reaction was stirred at 80 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with ethyl acetate (EA) (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. After filtration, the filtrate was concentrated under reduced pressure to give 3-[4-[4-(4-nitrophenyl)piperidine-2,6-dione -1-yl]anilino]piperidine-2,6-dione (140 mg, 31% yield, 95% purity). LCMS (ESI ⁺ ) m/z 410.1 [M+H] ⁺ , RT: 0.483 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.76 (s, 1H, NH), 8.07 (d, J = 9.4 Hz, 2H), 7.09 (d, J = 9.4 Hz, 2H), 6.82 (d, J = 8.8 Hz, 2H), 6.64 (d, J = 8.8 Hz, 2H), 5.45 (d, J = 7.3 Hz, 1H, NH), 4.21 (ddd, J = 11.2, 6.8, 4.8 Hz, 1H), 3.64 - 3.55 (m, 4H), 3.10 - 3.02 (m, 4H), 2.73 (ddd, J = 17.4, 11.8, 5.6 Hz, 1H), 2.57 (ddd, J = 17.6, 4.4, 4.0 Hz, 1H), 2.11 (ddd, J = 12.9, 8.8, 4.4 Hz, 1H), 1.85 (ddd, J = 24.1, 11.5, 4.3 Hz, 1H).

Step 2: At 25°C, 3-[4-[4-(4-nitrophenyl)piperidin To a solution of 3-[4-[(4-aminophenyl)piperidin-2,6-dione (from step 1) (140 mg, 324 µmol, 95% purity) in TFE (3 mL) was added Pd/C (40.2 mg, 10% on carbon). The reaction was stirred at 25 °C under _H2 atmosphere (15 psi) for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was filtered and the filter cake was washed with TFE (20 mL). The collected filtrate was concentrated to give the intermediate 3,3- [4-[4-(4-aminophenyl)piperidin-2,6-dione -1-yl]anilino]piperidine-2,6-dione (70.0 mg, 54% yield, 94.91% purity). LCMS (ESI ⁺ ) m/z 380.2 [M+H] ⁺ , RT: 0.559 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ = 10.76 (br s, 1H, NH ), 6.80 (br d, J = 8.8 Hz, 2H), 6.73 (d, J = 8.8 Hz, 2H), 6.63 (br d, J = 8.8 Hz, 2H), 6.51 (d, J = 8.8 Hz, 2H), 5.40 (d, J = 7.3 Hz, 1H, NH ), 4.58 (br s, 2H, NH ₂ ), 4.20 (ddd, J = 11.2, 6.8, 5.0 Hz, 1H), 3.10 - 3.00 (m, 8H), 2.73 (ddd, J = 17.4, 11.8, 5.6 Hz, 1H), 2.58 (ddd, J = 17.4, 4.4, 4.4 Hz, 1H), 2.11 (ddd, J = 12.9, 8.8 Hz, 1H), 1.84 (ddd, J = 24.1, 12.0, 4.5 Hz, 1H). Intermediate 4 3-((4-(4-(3-(4-aminophenyl)propyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione (Figure 7)

Step 1: Boc - protected intermediate 4 was prepared according to the procedure described in step 1 of intermediate 1, using tert-butyl (4-(3-oxopropyl)phenyl)carbamate (references: WO 2012/177061, CN 103649199 A) instead of tert-butyl (4-formylphenyl)carbamate. The reaction was directly purified by preparative TLC (EA: MeOH = 10:1, Rf = 0.4) to give Boc -protected intermediate 4 (0.18 g, 60% yield, 95% purity). LCMS (ESI ⁺ ) m/z 522.3 [M+H] ⁺ , RT: 0.578 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH), 9.22 (br s, 1H, NH), 7.35 (br d, J = 8.1 Hz, 2H), 7.09 (br d, J = 8.1 Hz, 2H), 6.76 (br d, J = 8.6 Hz, 2H), 6.61 (br d, J = 8.6 Hz, 2H), 5.41 (br s, 1H), 4.19 (ddd, J = 10.2, 6.8, 4.8 Hz, 1H), 3.04 - 2.82 (m, 4H), 2.79 - 2.65 (m, 3H), 2.63 - 2.57 (m, 9H)。

Step 2: Intermediate 4 was prepared following the procedure described in step 2 of intermediate 1. The mixture was concentrated at 40°C under reduced pressure to give the product. The product was used in the next step without further purification. Intermediate 4 was obtained, 3-((4-(4-(3-(4-aminophenyl)propyl)piperidin (4-(4-yl)phenyl)amino)piperidine-2,6-dione (81.0 mg, 192 µmol, 56% yield, 95% purity). LCMS (ESI ⁺ ) m/z 422.2 [M+H] ⁺ , RT: 0.152 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH 2 ), 6.84 (d, J = 8.2 Hz, 2H), 6.74 (d, J = 8.9 Hz, 2H), 6.60 (d, J = 8.9 Hz, 2H), 6.47 (d, J = 8.2 Hz, 2H), 5.36 (d, J = 7.2 Hz, 1H), 4.79 (br s, 2H, NH ₂ ), 4.18 (ddd, J = 11.3, 6.9, 4.9 Hz, 1H), 3.00 - 2.86 (m, 4H), 2.72 (ddd, J = 17.5, 11.8, 5.6 Hz, 3H), 2.57 (ddd, J = 17.5, 4.2, 4.2 Hz, 1H), 2.47 (br s, 4H), 2.42 (br t, J = 7.6 Hz, 2H), 2.35 - 2.24 (m, 2H), 2.10 (ddd, J = 13.3, 8.7, 4.4 Hz, 1H), 1.83 (ddd, J = 24.2, 11.5, 4.4 Hz, 1H), 1.66 (ddd, J = 14.5, 7.4, 7.4 Hz, 2H). -1-yl)phenyl)carbamic acid tributyl ester (Figure 8)

Step 1: To a mixture of 1-bromo-3-nitrobenzene (0.500 g, 2.48 mmol) in toluene (8 mL) at 20 °C was added N- (4-piperidin -1-ylphenyl)carbamic acid tributyl ester (reference: WO 2001/97810, page 41, 824 mg, 2.97 mmol), BINAP (154 mg, 248 µmol), Pd(OAc) ₂ (55.6 mg, 248 µmol), and Cs ₂ CO ₃ (1.61 g, 4.95 mmol). The reaction was stirred at 100 °C under N ₂ for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was poured into H ₂ O (10 mL). The mixture was extracted with DCM (3 × 10 mL). The organic phase was washed with brine (5 × 10 mL), dried over anhydrous Na ₂ SO ₄ , and filtered. The filtrate was concentrated under reduced pressure to give a crude product. The crude product was purified by preparative TLC (PE:EA = 0:1, Rf = 0.5) to give N- [4-[4-(3-nitrophenyl)piperidin -1-yl]phenyl]carbamic acid tributyl ester, intermediate 5 precursor (0.700 g, 54% yield, 76% purity). LCMS (ESI ⁺ ) m/z 399.2 [M+H] ⁺ , RT: 0.672 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 9.07 (br s, 1H, NH), 7.73 - 7.68 (m, 1H), 7.61 (ddd, J = 7.2, 2.0, 2.0 Hz, 1H), 7.54 - 7.43 (m, 2H), 7.32 (br d, J = 8.8 Hz, 2H), 6.92 (d, J = 8.8 Hz, 2H), 3.45 - 3.38 (m, 4H), 3.23 - 3.16 (m, 4H), 1.46 (s, 9H).

Step 2: To a solution of the product of step 1 (0.700 g, 1.34 mmol, 76% purity) in THF (10 mL) under _N2 was added Pd/C (285 mg, 268 µmol, 10% purity). The suspension was degassed under vacuum and purged with _H2 several times. The mixture was stirred under _H2 (15 psi) at 25 °C for 12 h. LCMS showed that the reaction was complete and the starting material was consumed, and the desired product was detected. The mixture was filtered, and the filtrate was concentrated to give intermediate 5 , N- [4-[4-(3-aminophenyl)piperidin-1-yl]-piperidin-1-yl]-piperidin-1-yl]-piperidin-1-yl]-piperidin-1-yl]-piperidin-1-yl]-piperidin-1-yl -1-yl]phenyl]carbamic acid tributyl ester (0.500 g, 91% yield, 90.15% purity). LCMS (ESI ⁺ ) m/z 369.3 [M+H] ⁺ , RT: 0.863 min. Intermediate 6 3-((3-(4-(4-aminophenyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione (Figure 9)

Step 1: Intermediate 5 (0.500 g, 1.36 mmol, 90.15% purity) was reacted with dichloromethane To a mixture of 4-(2-bromopiperidine-2,6-dione (313 mg, 1.63 mmol), DIEA (351 mg, 2.71 mmol), and NaI (40.7 mg, 271 µmol) in 2-(4-oxane) (6 mL) was added. The mixture was stirred at 100 °C under _N2 for 12 h. LCMS showed that the reaction was complete and the starting material was consumed, and the desired product was detected. The mixture was poured into _H2O (30 mL). The mixture was extracted with DCM (3 × 30 mL). The organic phase was washed with brine (3 × 30 mL), dried over _{anhydrous Na2SO4} , and filtered. The filtrate was concentrated under reduced pressure to give Boc protected intermediate 6 (0.30 g, 43.54% yield, 85.15% purity). LCMS (ESI ⁺ ) m/z 480.3 [M+H] ⁺ , RT: 0.853 min.

Step 2: A mixture of Boc protected intermediate 6 (0.500 g, 888 µmol, 85.15% purity) in DCM (10 mL) and TFA (1 mL) was stirred at 20 °C under _N2 for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was poured into NaHCO3 solution (10 mL). The mixture was extracted with DCM (3 × 10 mL). The organic phase was washed with brine (5 × 10 mL), dried over anhydrous _Na2SO4 , and filtered. The filtrate was concentrated under reduced pressure to give intermediate 6, ₃ -((3-(4-( ₄ -aminophenyl)piperidin-2-yl)-1-piperidin-2-yl)-1-piperidin-2-yl)-1-piperidin-2-yl)-1-piperidin-2-yl)-1-piperidin-2-yl) -1 - piperidin -2-yl)-1-piperidin-2-yl)-1-piperidin-2-yl 1-(4-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidine-2,6-dione (0.25 g, 37% yield, 50.47% purity) was used in the next reaction without further purification. LCMS (ESI ⁺ ) m/z 380.2 [M+H] ⁺ , RT: 0.685 min. Intermediate 7 1-(4-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidine-4-carboxaldehyde (Figure 10)

Step 1: To a solution of [1-(4-aminophenyl)-4-piperidinyl]methanol (reference: WO 2021/127561, 1.00 g, 4.65 mmol, 95.97% purity) and 3-bromopiperidine-2,6-dione (893 mg, 4.65 mmol) in DMF (15.0 mL) at 25°C, NaHCO ₃ (782 mg, 9.30 mmol) was added. The reaction was stirred at 60°C under N ₂ for 2 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was concentrated at 40°C under reduced pressure to give the crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 3:1 to 0:1) to give 3-[4-[4-(hydroxymethyl)-1-piperidinyl]anilino]piperidine-2,6-dione (0.978 g, 3.02 mmol, 65% yield, 98.16% purity). LCMS (ESI ⁺ ) m/z 318.2 [M+H] ⁺ , RT: 0.617 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH), 6.75 (d, J = 8.9 Hz, 2H), 6.59 (d, J = 8.9 Hz, 2H), 5.35 (d, J = 7.2 Hz, 1H), 4.44 (t, J = 5.3 Hz, 1H), 4.18 (ddd, J = 11.3, 7.0, 4.8 Hz, 1H), 3.38 (br d, J = 11.9 Hz, 2H), 3.28 (t, J = 5.8 Hz, 2H), 2.79 - 2.66 (m, 1H), 2.62 - 2.53 (m, 1H), 2.48 - : 2.40 (m, 2H), 2.15 - 2.05 (m, 1H), 1.89 - 1.77 (m, 1H), 1.72 (br d, J = 10.8 Hz, 2H), 1.48 - 1.34 (m, 1H), 1.23 (dq, J = 12.0, 4.1 Hz, 2H).

Step 2: To a mixture of 3-[4-[4-(hydroxymethyl)-1-piperidinyl]anilino]piperidine-2,6-dione (0.700 g, 2.16 mmol, 98.16% purity) in DCM (12.0 mL) was added TEA (2.19 g, 21.65 mmol), pyridine; sulfur trioxide (2.21 g, 13.9 mmol), and DMSO (1.69 g, 21.7 mmol). The reaction was stirred at 25 °C under _N2 for 12 h. _LCMS showed the reaction was complete and the desired product was detected. The reaction was extracted with DCM (3 × 60 mL). The organic layer was dried over _Na2SO4 . After filtration, the filtrate was concentrated under reduced pressure to give intermediate 7 , 1-(4-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidine-4-carbaldehyde (0.35 g, 31% yield, 60.12% purity). LCMS (ESI ⁺ ) m/z 316.2 [M+H] ⁺ , RT: 0.677 min. Intermediate 8 ( R )-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-6-((4-(piperidin-3-yl)amino)phenyl)piperidine-4-carbaldehyde -1-yl)phenyl)amino)-1,2-dihydro- 3H -pyrazolo[3,4- d ]pyrimidin-3-one (Figure 11)

Step 1: In a 125 mL round-bottom flask, ( R )-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-6-(methylthio) -1H -pyrazolo[3,4-d]pyrimidin-3( 2H )-one (reference: WO 2019/173082 A1) was added and cooled to 0°C. m -CPBA (616 mg, 2.75 mmol) was slowly added to the flask. The reaction was continued at room temperature (rt) for 1 h and then cooled back to 0°C. 4-(4-aminophenyl)piperidin -1-Carboxylic acid tributyl ester (832 mg, 3.00 mmol) and DIEA (2.183 mL, 12.50 mmol) were added to the mixture. The reaction was continued at rt for 16 h. Water (30 mL) was added to the mixture and extracted with EtOAc (2 × 50 mL). The combined organic layers were washed with saturated aqueous NaHCO ₃ solution and brine, dried over sodium sulfate, and evaporated to obtain a black residue, which was then purified by silica gel column chromatography using Combi-Flash, eluting with DCM-MeOH (0 to 10%). The pure product fractions were combined and evaporated to give ( R )-tert-butyl 4-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin- -1-carboxylate (1.15 g, 1.88 mmol, 75% yield). LC/MS (ESI ⁺ ) m/z 613.4 [M+H] ⁺ .

Step 2: In a 25 mL round bottom flask, the product of step 1 (225 mg, 0.367 mmol) was dissolved in dichloromethane (3 mL) and cooled to 0 °C. 2N HCl in ether (1 mL) was added to the mixture and the reaction was continued at this temperature for 3 h. The reaction was quenched with cold saturated aqueous NaHCO ₃ solution and extracted with dichloromethane (3 × 15 mL). The combined organic layers were washed with brine, dried over sodium sulfate, and evaporated. The residue was purified on silica gel column chromatography using dichloromethane-MeOH (0 to 100%). The product fractions were combined and evaporated to give intermediate 8 , (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-((4-piperidin- -1-yl)phenyl)amino)-1H-pyrazolo[3,4-d]pyrimidin-3(2H)-one (150 mg, 0.293 mmol, 80% yield). LC/MS (ESI ⁺ ) m/z 513.41 [M+H] ⁺ . Intermediate 9 1-(4-nitrophenyl)-N-(piperidin-4-yl)piperidin-4-amine (Figure 12)

Step 1: To a stirred solution of tributyl 4-aminopiperidine-1-carboxylate (1.09 g, 5.45 mmol) and 1-(4-nitrophenyl)piperidin-4-one (1.00 g, 4.54 mmol) in 1,2-dichloroethane (10 mL) at 0 °C, acetic acid (2.5 mL) was added dropwise and the reaction was stirred at rt for 2 h. To this mixture was added sodium triacetoxyborohydride (2.41 g, 11.4 mmol) portionwise at 0 °C and the mixture was stirred at rt for another 16 h. After completion, the mixture was diluted with DCM (100 mL) and washed with water (2 x 50 mL) and brine (50 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to get the crude compound. The crude was purified by combi-flash chromatography (silica gel) using 0 to 5% methanol in DCM as eluting solvent to give tributyl 4-((1-(4-nitrophenyl) -N -piperidin-4-yl)amino)piperidine-1-carboxylate (1.05 g, 57%). LC/MS (ESI ⁺ ) m/z 405.42 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.11 (d, J = 9.5, Hz, 2H), 6.82 (d, J = 9.5 Hz, 2H), 5.65 (br s, 1H), 4.14 (br s, 2H), 3.98 (br d, J = 13.2 Hz, 2H), 3.18 - 3.08 (m, 1H), 3.07 - 2.94 (m, 3H), 2.84 - 2.70 (m, 2H), 2.20 - 2.09 (m, 2H), 2.07 - 1.94 (m, 2H), 1.82 - 1.68 (m, 2H), 1.67 - 1.50 (m, 2H), 1.45 (s, 9H).

Step 2: To a stirred solution of tributyl 4-((1-(4-nitrophenyl) -N -piperidin-4-yl)amino)piperidine-1-carboxylate (1.30 g, 3.21 mmol) in DCM (13 mL) at 0 °C, trifluoroacetic acid (5 mL) was added dropwise and the mixture was stirred at rt for 2 h. After completion, the mixture was concentrated in vacuo to get a residue, which was washed with diethyl ether (10 mL). The obtained product was dissolved in 20% MeOH in DCM (100 mL) and washed with saturated _NaHCO3 solution (2 x 100 mL) and brine solution (100 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to give 1-(4-nitrophenyl) -N- (piperidin-4-yl)piperidin-4-amine (0.900 g, 92%). LC/MS (ESI ⁺ ) m/z 305.15 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.10 (d, J = 9.6 Hz, 2H), 6.81 (d, J = 9.6 Hz, 2H), 3.92 (br d, J = 13.2 Hz, 2H), 3.16 (br d, J = 12.8 Hz, 2H), 3.09 - 2.97 (m, 2H), 2.97 - 2.86 (m, 1H), 2.79 - 2.62 (m, 3H), 2.02 - 1.86 (m, 4H), 1.48 - 1.35 (m, 2H), 1.35 - 1.22 (m, 2H). Intermediate 10 3-(4-(4-((1-(4-aminophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (Figure 13)

Step 1: At rt, intermediate 9 (800 mg, 2.63 mmol), methyl 2-(4-bromophenyl)acetate (783 mg, 3.42 mmol) in 1,4-dihydro-1,4-pyridine was reacted with 1,4-dihydro-1,4-pyridine. To a stirred solution in 2-oxane (10 mL), potassium phosphate (1.67 g, 7.87 mmol) was added, and the mixture was degassed with nitrogen for 15 min. To this mixture was added dipalladium tris(dibenzylideneacetone) (0) (241 mg, 0.263 mmol) and X-Phos (125 mg, 0.263 mmol). The mixture was stirred at 120 °C for 16 h. After completion, the mixture was diluted with ice-cold 10% aqueous AcOH (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude was purified by combi-flash chromatography (silica gel, column 40 g) using 0 to 7% MeOH in DCM as eluent to give methyl 2-(4-(4-((1-(4-nitrophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)acetate (705 mg, 59%). LC/MS (ESI ⁺ ) m/z 453.67 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.11 (d, J = 9.2 Hz, 2H), 7.16 (d, J = 8.8 Hz, 2H), 6.88 (d, J = 8.4 Hz, 2H), 6.81 (d, J = 9.6 Hz, 2H), 3.67 (s, 3H), 3.66 (d, J = 13.2 Hz, 2H), 3.54 (s, 2H), 3.07-2.88 (m, 5H), 2.77-2.70 (m, 2H), 2.10-2.04 (m, 4H), 1.67-1.62 (m, 4H).

Step 2: To a stirred solution of methyl 2-(4-(4-((1-(4-nitrophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)acetate (0.6 g, 1.326 mmol) from step 1 in DMF (6 mL) at -10 °C was added acrylamide (0.104 g, 1.46 mmol) and potassium tert-butoxide (1 M solution in THF, 1.46 mL, 1.46 mmol). The mixture was mixed at -10 °C to 0 °C for 2 h. The progress of the reaction was monitored by TLC. After completion, the reaction was quenched with water (100 mL) and extracted with 10% MeOH in DCM (2 x 50 mL). The organic layer was washed with brine (50 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 5% MeOH in DCM as eluent to give 3-(4-(4-((1-(4-nitrophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (0.355 g, 54%). LC/MS (ESI ⁺ ) m/z 492.75 [M+H] ⁺ .

Step 3: To a stirred solution of 3-(4-(4-((1-(4-nitrophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione from step 2 (0.250 g, 0.509 mmol) in MeOH (3 mL) in a 100 mL round-bottom flask under nitrogen atmosphere was added 10% palladium on activated carbon (50% wet, 0.250 g) and the mixture was hydrogenated using a hydrogen balloon at rt for 16 h. After completion, the reaction mixture was filtered through a diatomaceous earth pad, and the filtrate was concentrated under reduced pressure to give intermediate 10,3- (4-(4-((1-(4-aminophenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (0.160 g, 68%). LC/MS (ESI ⁺ ) m/z 462.33 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H), 8.82 (br s, 2H), 7.06 (d, J = 8.4 Hz, 2H), 6.93 (d, J = 8.4 Hz, 2H), 6.76 (d, J = 8.4 Hz, 2H), 6.58 (d, J = 8.4 Hz, 2H), 5.59 (br s, 1H), 3.85 - 3.70 (m, 3H), 3.69 - 3.75 (m, 1H), 3.44 (br d, J = 11.6 Hz, 2H), 3.19 - 3.09 (m, 1H), 2.78 (t, J = 12.0 Hz, 2H), 2.70 - 2.55 (m, 3H), 2.19 - 1.95 (m, 5H), 1.79 - 1.60 (m, 4H), 1.30 - 1.18 (m, 2H). Intermediate 11 1-((1-(4-nitrophenyl)piperidin-4-yl)methyl)piperidin-4-yl

At 0 ° C, 4-((1-(4-nitrophenyl)piperidin-4-yl)methyl)piperidin-4-yl) -1-carboxylic acid tributyl ester (reference: US 2018/0099940, 3.10 g, 7.66 mmol) was added dropwise to a stirred solution in DCM (30 mL), trifluoroacetic acid (6 mL) was added dropwise, and the mixture was stirred at rt for 2 h. After completion, the mixture was concentrated in vacuo to give a crude product, which was washed with diethyl ether (25 mL). The obtained product was redissolved in 20% MeOH in DCM (200 mL) and washed with saturated NaHCO ₃ solution (2 × 100 mL) and brine solution (100 mL). The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to give intermediate 11 , 1-((1-(4-nitrophenyl)piperidin-4-yl)methyl)piperidin-4-yl)methyl)piperidin-4-yl (2.05 g, 87%). LCMS (ESI ⁺ ) m/z 305.31 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.17 (d, J = 9.4 Hz, 2H), 6.86 (d, J = 9.4 Hz, 2H), 4.02 (br d, J = 12.8 Hz, 2H), 3.06 - 2.96 (m, 6H), 2.47 (br s, 4H), 2.26 (d, J = 6.8 Hz, 2H), 2.03 - 1.93 (m, 3H), 1.38 - 1.27 (m, 2H). Intermediate 12 3-(4-(4-((1-(4-aminophenyl)piperidin-4-yl)methyl)piperidin- -1-yl)phenyl)piperidin-2,6-dione (Figure 14)

Intermediate 12 was prepared by following a similar procedure as described for Intermediate 10 , using Intermediate 11 (1.000 g, 3.285 mmol) instead of Intermediate 9 to provide Intermediate 12 , 3-(4-(4-((1-(4-aminophenyl)piperidin-4-yl)methyl)piperidin-4-yl)methyl)piperidin-4-yl LCMS (ESI ⁺ ) m/z 462.57 [M+H] ⁺ . Intermediate 13 3-(4-(4-aminopiperidin-1-yl)phenyl)piperidin-2,6-dione (Figure 15)

Intermediate 13 was prepared by following a similar procedure as described in step 2 of intermediate 12 using methyl 2-(4-(4-((tri-butyloxycarbonyl)amino)piperidin-1-yl)phenyl)acetate (reference: US 2016/0068512, 1.00 g, 2.87 mmol) to provide Boc-protected intermediate 13. The Boc group was removed by standard TFA/DCM procedures to give intermediate 13 , the TFA salt of 3-(4-(4-aminopiperidin-1-yl)phenyl)piperidine-2,6-dione (49% and 99% for two steps). LCMS (ESI ⁺ ) m/z 288.47 [M+H] ⁺ . Intermediate 14 3-(4-(4-(((1-(4-aminophenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (Figure 16)

Step 1: To a stirred solution of intermediate 13 TFA salt (540 mg, 1.40 mmol) and 1-(4-nitrophenyl)piperidine-4-carbaldehyde (reference: US 2021/0087170 P54 (for similar procedure), 328 mg, 1.40 mmol) in DCE (10 mL) was added acetic acid (0.1 mL) at rt. The mixture was stirred at rt for 1 h. To this mixture was added NaBH(OAc) ₃ (595 mg, 2.80 mmol) at 0 °C, and the resulting mixture was stirred at rt for 16 h. The reaction was quenched with water (35 mL) and extracted with dichloromethane (2 × 50 mL). The organic layer was washed with water (20 mL) and saturated sodium bicarbonate solution (20 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was purified by silica gel flash chromatography using 0 to 60% MeOH in DCM as eluent to give 3-(4-(4-(((1-(4-nitrophenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (460 mg, 65%). LCMS (ESI ⁺ ) m/z 506.59 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 8.32 (br s, 1H, NH), 8.05 (d, J = 9.6 Hz, 2H), 7.06 (d, J = 8.8 Hz, 2H), 7.04 (d, J = 9.6 Hz, 2H), 6.92 (d, J = 8.8 Hz, 2H), 4.08 (br d, J = 10.6 Hz, 2H), 3.81 (br d, J = 12.0 Hz, 2H), 3.75 - 3.60 (m, 1H), 3.30 - 3.15 (m, 1H), 3.00 (t, J = 11.6 Hz, 2H), : 2.89 (br s, 2H), 2.74 (t, J = 12.0 Hz, 2H), 2.70 - 2.58 (m, 1H), 2.54 - 2.45 (m, 1H), 2.20 - 2.05 (m, 1H), 2.05 - 1.88 (m, 4H), 1.84 (br d, J = 13.2 Hz, 2H), 1.67 - 1.50 (m, 2H), 1.30 - 1.20 (m, 2H).

Step 2: To a stirred solution of 3-(4-(4-(((1-(4-nitrophenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (0.202 g, 0.4 mmol) in MeOH (10.1 mL) under nitrogen atmosphere was added 10% palladium on carbon (50% wet, 0.170 g) at rt, and the mixture was hydrogenated using a hydrogen balloon at rt for 2 h. The reaction progress was monitored by TLC. After completion of the reaction, the mixture was filtered through a celite bed and washed with MeOH (10 mL). The filtrate was concentrated under reduced pressure to provide intermediate 14 , 3-(4-(4-(((1-(4-aminophenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (190 mg, 99%). LCMS (ESI ⁺ ) m/z 476.63 [M+H] ⁺ . Intermediate 15 3-(4-(2-aminoethoxy)phenyl)piperidine-2,6-dione (Figure 17)

Step 1: Intermediate 15 was prepared by following a similar procedure as described in Intermediate 13 , using methyl 2-(4-(2-((tert-butyloxycarbonyl)amino)ethoxy)phenyl)acetate (reference: WO 2019/243576, 1.20 g, 3.88 mmol) instead of methyl 2-(4-(4-((tert-butyloxycarbonyl)amino)piperidin-1-yl)phenyl)acetate to provide Boc-protected intermediate 15 , tri-butyl (2-(4-(2,6-dihydroxypiperidin-3-yl)phenoxy)ethyl)carbamate (0.740 g, 55%). LCMS (ESI ⁺ ) m/z 347.07 [MH] ^- . ¹ H NMR (400 MHz, CDCl ₃ ) δ 10.78 (s, 1H, NH), 7.12 (d, J = 8.4 Hz, 2H), 6.99 (br t, J = 6.2 Hz, 1H), 6.88 (d, J = 8.4 Hz, 2H), 3.94 (t, J = 6.0 Hz, 2H), 3.78 (dd, J = 11.4, 5.0 Hz, 1H), 3.34 - 3.24 (m, 2H), 2.72 - 2.58 (m, 1H), 2.52 - 2.46 (m, 1H), 2.23 - 2.10 (m, 1H), 2.07 - 1.98 (m, 1H), 1.38 (s, 9H).

Step 2: The Boc group was removed by standard TFA/DCM procedure to give intermediate 15 , 3-(4-(2-aminoethoxy)phenyl)piperidine-2,6-dione as TFA salt (97%). LCMS (ESI ⁺ ) m/z 249.24 [M+H] ⁺ . Intermediate 16 3-(4-(2-(((1-(4-aminophenyl)piperidin-4-yl)methyl)amino)ethoxy)phenyl)piperidine-2,6-dione (Figure 18)

Intermediate 16 was prepared by following the same procedure described for Intermediate 14 , using Intermediate 15 (0.500 g, 2.01 mmol) instead of Intermediate 13 , to provide Intermediate 16 , 3-(4-(2-(((1-(4-aminophenyl)piperidin-4-yl)methyl)amino)ethoxy)phenyl)piperidine-2,6-dione (0.21 g, 42% and 56% for two steps). LCMS (ESI ^- ) m/z 435.45 [MH] ^- . Intermediate 17 3-(4-((1-((1-(4-aminophenyl)piperidin-4-yl)methyl)piperidin-4-yl)oxy)phenyl)piperidine-2,6-dione (Figure 19)

Intermediate 17 was prepared by following the same procedure described for Intermediate 14 , using 3-(4-(piperidin-4-yloxy)phenyl)piperidine-2,6-dione (0.250 g, 0.867 mmol) instead of Intermediate 13 , providing Intermediate 17 , 3-(4-((1-((1-(4-aminophenyl)piperidin-4-yl)methyl)piperidin-4-yl)oxy)phenyl)piperidine-2,6-dione (0.18 g, 57% and 74% for two steps). LCMS (ESI ⁺ ) m/z 477.65 [M+H] ⁺ . Intermediate 18 2',6'-dioxo-[1,3'-bipiperidinyl]-4-carbaldehyde (Figure 20)

Step 1: To a mixture of 3-bromopiperidine-2,6-dione (0.500 g, 2.60 mmol) in DMF (5 mL) at 20 °C, 4-piperidinylmethanol (330 mg, 2.86 mmol) and DIEA (673 mg, 5.21 mmol) were added. Then, the mixture was stirred at 80 °C under _{N2 for} 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was filtered, and the filtrate was purified by preparative HPLC ( _NH4HCO3 conditions) to provide 3-[4-(hydroxymethyl)-1-piperidinyl]piperidine-2,6-dione (0.250 g, 37% yield, 87.62% purity). LCMS (ESI ⁺ ) m/z 227.2 [M+H] ⁺ , RT: 0.496 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.54 (br s, 1H, NH), 4.38 (br s, 1H, OH), 3.40 - 3.34 (m, 2H), 3.26 - 3.18 (m, 2H), 2.82 - 2.70 (m, 2H), 2.59 - 2.50 (m, 2H), 2.40 - 2.30 (m, 1H), 2.06 - 1.93 (m, 1H), 1.88 - 1.79 (m, 1H), 1.66 - 1.55 (m, 2H), 1.39 - 1.25 (m, 1H), 1.14 - 1.01 (m, 2H).

Step 2: To a mixture of 3-[4-(hydroxymethyl)-1-piperidinyl]piperidine-2,6-dione from step 1 (0.250 g, 968 µmol, 87.62% purity) in DCM (3 mL) was added TEA (980 mg, 9.68 mmol), pyridine-sulfur trioxide (986 mg, 6.20 mmol), and DMSO (756 mg, 9.68 mmol) at 0 °C. The mixture was stirred at 40 °C under _N2 for 1 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was poured into _H2O (10 mL). The mixture was extracted with DCM (3 x 10 mL). The organic phase was washed with brine (5 mL), dried over _{anhydrous Na2SO4} , and concentrated in vacuo to give intermediate 18 , 1-(2,6-dioxo-3-piperidinyl)piperidine-4-carboxaldehyde (0.150 g, 68% yield, 98.30% purity). LCMS (ESI ⁺ ) m/z 225.2 [M+H] ⁺ , RT: 0.513 min. Intermediate 19 4-((4-(4-aminophenyl)piperidinyl)piperidinyl -1-yl)methyl)-[1,3'-bipiperidinyl]-2',6'-dione (Figure 21)

Step 1: To a mixture of intermediate 18 (0.150 g, 658 μmol, 98.30% purity) in DCM (5 mL) at 0 °C was added N- (4-piperidin To the mixture was added tributyl 1-(4-((2',6'-dihydroxy-[1,3'-bipiperidinyl]-4-yl)methyl)piperidinyl)carbamate (182 mg, 658 µmol) and NaBH(OAc) ₃ (279 mg, 1.32 mmol). The mixture was stirred at 20 °C under N ₂ for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was poured into H ₂ O (10 mL). The mixture was extracted with DCM (3 × 10 mL). The organic phase was washed with brine (10 mL), dried over anhydrous Na ₂ SO ₄ , and concentrated in vacuo to give the Boc -protected intermediate 19 , (4 ... =Tributyl 1-(1-yl)phenyl)carbamate (0.400 g, 44% yield). The crude product was used in the next step without purification. LCMS (ESI ⁺ ) m/z 486.3 [M+H] ⁺ , RT: 1.739 min.

Step 2: Deprotection was performed using standard TFA/DCM Boc. The residue was purified by preparative TLC (EA: MeOH = 3:1, Rf = 0.4) to provide pure intermediate 19 , 3-((4-(4-aminophenyl)piperidin -1-yl)methyl)-[1,3'-bipiperidinyl]-2',6'-dione (0.120 g, 71% yield). LCMS (ESI ⁺ ) m/z 386.2 [M+H] ⁺ , RT: 1.134 min. Intermediate 21 (1-(3-aminophenyl)piperidin-4-yl)methanol (Figure 22)

Step 1: In a glove box, to a solution of 1-bromo-3-nitrobenzene (250 mg, 1.24 mmol) in toluene (8.0 mL) at 25 °C was added 4-piperidinylmethanol (171. mg, 1.49 mmol), _Cs2CO3 ( ₈₀₇ mg, 2.48 mmol), BINAP (77.1 mg, 124 µmol), and Pd(OAc) ₂ (27.8 mg, 124 µmol). The mixture was stirred at 100 °C for 12 h. LCMS showed that the starting material was consumed and a major product with the desired MS was detected. Seven additional reactions were set up as detailed above. After cooling to rt, all eight reaction mixtures were combined. The reaction solution was filtered through celite, and the filtrate was concentrated under reduced pressure to give a residue. The residue was purified by MPLC (Biotage, SiO ₂ ): (eluted with PE:EA = 1:0 to 2:1) to give (1-(3-nitrophenyl)piperidin-4-yl)methanol (0.900 g, 3.51 mmol, 35% yield, 92.14% purity). LCMS (ESI ⁺ ) m/z 237.1 [M+H] ⁺ , RT: 0.587 min. ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.73 (t, J = 2.2 Hz, 1H), 7.63 (dd, J = 8.2, 1.6 Hz, 1H), 7.36 (t, J = 8.2 Hz, 1H), 7.21 (dd, J = 8.2, 2.0 Hz, 1H), 3.87 - 3.78 (m, 2H), 3.58 (d, J = 6.3 Hz, 2H), 2.85 (td, J = 12.4, 2.4 Hz, 2H), 1.90 (br d, J = 13.4 Hz, 2H), 1.80 - 1.67 (m, 1H), 1.41 (qd, J = 12.2, 4.4 Hz, 2H).

Step 2: To a solution of (1-(3-nitrophenyl)piperidin-4-yl)methanol (0.900 g, 3.51 mmol, 92.14% purity) from step 1 in THF (30.0 mL) was added Pd/C (369 mg, 351 µmol, 10% purity, 10% palladium on carbon, wet, containing 50% water) at 25 °C. The mixture was degassed three times with hydrogen and then stirred under _H2 (15 psi) at 25 °C for 12 h. LCMS showed that the starting material was consumed and a major product with the desired MS was detected. The reaction solution was filtered through celite, and the filtrate was concentrated under reduced pressure to give intermediate 21 , (1-(3-aminophenyl)piperidin-4-yl)methanol (0.500 g, 2.09 mmol, 59% yield, 86.03% purity). The crude product was used directly in the next step without purification. LCMS (ESI ⁺ ) m/z 207.1 [M+H] ⁺ , RT: 0.477 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 6.81 (t, J = 7.9 Hz, 1H), 6.14 (d, J = 1.6 Hz, 1H), 6.10 (dd, J = 7.9, 1.6 Hz, 1H), 5.99 (dd, J = 7.9, 1.4 Hz, 1H), 4.69 (br s, 2H, NH ₂ ), 3.56 (br d, J = 12.3 Hz, 2H), 3.27 (d, J = 6.2 Hz, 2H), 2.54 (td, J = 12.0, 2.0 Hz, 2H), 1.70 (br d, J = 12.1 Hz, 2H), 1.54 - 1.40 (m, 1H), 1.19 (qd, J = 12.2, 3.8 Hz, 2H). Intermediate 22 1-(3-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidine-4-carboxaldehyde (Figure 23)

Intermediate 22 was prepared by following a similar procedure as described in Intermediate 7 using Intermediate 21 (0.500 g, 2.09 mmol, 86.03% purity) instead of [1-(4-aminophenyl)-4-piperidinyl]methanol to provide 1-(3-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidine-4-carbaldehyde in 46% and 26% yields for step 1 and step 2, respectively.

Analytical data of step 1 product: LCMS (ESI ⁺ ) m/z 318.2 [M+H] ⁺ , RT: 0.315 min. ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.08 (br s, 1H), 7.11 (t, J = 8.1 Hz, 1H), 6.45 (dd, J = 8.4, 2.0 Hz, 1H), 6.29 (t, J = 2.1 Hz, 1H), 6.17 (dd, J = 8.0, 2.0 Hz, 1H), 4.67 (br s, 1H), 4.09 (dd, J = 12.0, 4.4 Hz, 1H), 3.69 (br d, J = 12.3 Hz, 2H), 3.55 (d, J = 6.4 Hz, 2H), 2.91 - 2.83 (m, 1H), 2.81 - 2.68 (m, 3H), 2.62 - 2.53 (m, 1H), 1.90 (qd, J = 13.0, 4.8 Hz, 1H), 1.85 (br d, J = 12.3 Hz, 2H), 1.69 - 1.62 (m, 1H), 1.40 (qd, J = 12.2, 4.0 Hz, 2H).

Analytical data of intermediate 22 : LCMS (ESI ⁺ ) m/z 316.2 [M+H] ⁺ , RT: 1.357 min. Intermediate 23 6-(4-(2,6-dioxopiperidin-3-yl)phenyl)-2,6-diazaspiro[3.3]heptane-2-carboxylic acid tributyl ester (Figure 24)

Step 1: 2,6-Bisbenzyloxy-3-bromo-pyridine (5.000 g, 13.50 mmol) was added to dichloromethane at 25 °C. To a solution of (4-dihydroxyborylphenyl)boronic acid (4.500 g, 27.01 mmol), Pd(dppf)Cl ₂ (1.50 g, 2.03 mmol), H ₂ O (20 mL), K ₂ CO ₃ (5.700 g, 27.01 mmol) in 2-oxane (100 mL) were added. The reaction was stirred at 80 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with EA (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO ₄ . The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 35:1) to give [4-(2,6-bisbenzyloxy-3-pyridyl)phenyl]boronic acid (2.0 g, 26% yield, 71.76% purity). LCMS (ESI ⁺ ) m/z 412.2 [M+H] ⁺ , RT: 0.977 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.03 (s, 2H), 7.80 (d, J = 8.2 Hz, 2H), 7.76 (d, J = 8.0 Hz, 2H), 7.52 (d, J = 8.2 Hz, 2H), 7.46 - 7.42 (m, 2H), 7.41 - 7.29 (m, 8H), 6.56 (d, J = 8.1 Hz, 1H), 5.48 (s, 2H), 5.39 (s, 2H).

Step 2: To a solution of boronic acid from step 1 (2.00 g, 3.49 mmol, 71.76% purity) in DCM (40 mL) was added tributyl 2,6-diazaspiro[3.3]heptane-2-carboxylate (346 mg, 1.74 mmol) and TEA (1.40 g, 13.8 mmol), Cu(OAc) ₂ (634 mg, 3.49 mmol) at 25 °C. The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was diluted with water (10 mL) and extracted with EA (3 x 10 mL). The combined organic layers were washed with brine (3 x 10 mL) and dried _{over Na2SO4} . The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 20:1) to give tert-butyl 6-[4-(2,6-bisbenzyloxy-3-pyridyl)phenyl]-2,6-diazaspiro[3.3]heptane-2-carboxylate (400 mg, 19% yield, 93.02% purity). LCMS (ESI ⁺ ) m/z 564.3 [M+H] ⁺ , RT: 1.110 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 7.64 (d, J = 8.1 Hz, 1H), 7.45 - 7.26 (m, 12H), 6.50 (d, J = 8.1 Hz, 1H), 6.44 (d, J = 8.7 Hz, 2H), 5.38 (s, 2H), 5.35 (s, 2H), 4.02 (br s, 4H), 3.93 (s, 4H), 1.38 (s, 9H).

Step 3: To a solution of the product from step 2 (400.0 mg, 660 µmol, 93.02% purity) in THF (10 mL) at 25°C was added Pd/C (10%, 66 mg, 62 µmol). The reaction was stirred at 25°C under _H2 atmosphere (15 psi) for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was filtered and the filter cake was washed with THF (20 mL), and the collected filtrate was concentrated to give Intermediate 23 , 6-(4-(2,6-dioxopiperidin-3-yl)phenyl)-2,6-diazaspiro[3.3]heptane-2-carboxylic acid tributyl ester (250.0 mg, 84% yield, 85.44% purity). LCMS (ESI ⁺ ) m/z 386.2 [M+H] ⁺ , RT: 0.793 min. Intermediate 24 3-(4-(6-((1-(4-aminophenyl)piperidin-4-yl)methyl)-2,6-diazaspiro[3.3]hept-2-yl)phenyl)piperidine-2,6-dione (Figure 25)

Step 1 of the preparation of intermediate 24 was Boc deprotection of intermediate 23 under standard TFA/DCM conditions with a yield of 98% and a purity of 86.25%. LCMS (ESI ⁺ ) m/z 286.2 [M+H] ⁺ , RT: 0.516 min.

Step 2 of the preparation of intermediate 24 follows the same procedure as described for intermediate 14 , using de-Boc intermediate 23 from step 1 (180 mg, 544 µmol, 86.25% purity) instead of intermediate 13 to react with tert-butyl (4-(4-formylpiperidin-1-yl)phenyl)carbamate (reference: WO 2007/075783) and provide Boc-protected intermediate 24 (200 mg, 46% yield, 71.01% purity). LCMS (ESI ⁺ ) m/z 574.4 [M+H] ⁺ , RT: 0.865 min.

Step 3 of the preparation of intermediate 24 was under standard TFA/DCM conditions. The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The reaction was concentrated under reduced pressure to give intermediate 24 , 3-(4-(6-((1-(4-aminophenyl)piperidin-4-yl)methyl)-2,6-diazaspiro[3.3]hept-2-yl)phenyl)piperidine-2,6-dione (100 mg, 51% yield, 59.48% purity). LCMS (ESI ⁺ ) m/z 474.3 [M+H] ⁺ , RT: 0.686 min. Intermediate 25 3-(4-(4-aminobutyloxy)phenyl)piperidine-2,6-dione (Figure 26)

Step 1: To a stirred solution of 4-(2,6-bis(benzyloxy)pyridin-3-yl)phenol (reference: WO 2022/012622, 1.30 g, 3.39 mmol), tributyl (4-hydroxybutyl)carbamate (0.962 g, 5.09 mmol), and triphenylphosphine (1.334 g, 5.085 mmol) in THF (10 mL) at 0°C, diisopropyl azodicarboxylate (1.028 g, 5.085 mmol) was slowly added, and the mixture was stirred at rt for 16 h. After the reaction was completed, water (10 mL) was added to quench the reaction. The mixture was concentrated under reduced pressure. The residue was diluted with water (50 mL) and DCM (100 mL). After phase separation, the aqueous phase was further extracted with DCM (100 mL), and the combined organic phases were concentrated under reduced pressure to give a residue. The crude product was purified by silica gel chromatography using 0 to 30% EtOAc in petroleum ether (PE) to give tert-butyl (4-(4-(2,6-bis(benzyloxy)pyridin-3-yl)phenoxy)butyl)carbamate (1.75 g, 93%). LCMS (ESI ^- ) m/z 553.37 [MH] ^- .

Step 2: To a stirred solution of tributyl (4-(4-(2,6-bis(benzyloxy)pyridin-3-yl)phenoxy)butyl)carbamate (1.70 g, 3.07 mmol) from step 1 in methanol (20 mL) was added 10% palladium on activated carbon (50% wet, 0.5 g) under nitrogen atmosphere and the resulting mixture was hydrogenated using a hydrogen balloon for 16 h. The mixture was filtered through a celite bed and the celite bed was washed with EA (40 mL). The organic layer was concentrated to give the crude compound. The crude compound was purified by silica gel flash chromatography using 0 to 50% EA in PE to give tert-butyl (4-(4-(2,6-dioxopiperidin-3-yl)phenoxy)butyl)carbamate (605 mg, 52%). LCMS (ESI ^- ) m/z 375.19 [MH] ^- . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.78 (s, 1H), 7.11 (d, J = 8.4 Hz, 2H), 6.87 (d, J = 8.4 Hz, 2H), 6.84 (t, J = 5.2 Hz, 1H), 3.94 (t, J = 6.4 Hz, 2H), 3.78 (dd, J = 11.4, 5.0 Hz, 1H), 2.98 (q, J = 6.4 Hz, 2H), 2.71 - 2.58 (m, 1H), 2.52 - 2.43 (m, 1H), 2.22 - 2.10 (m, 1H), 2.06 - 1.96 (m, 1H), 1.73 - 1.63 (m, 2H), 1.57 - 1.47 (m, 2H), 1.37 (s, 9H).

Step 3: To a stirred solution of tributyl (4-(4-(2,6-dioxopiperidin-3-yl)phenoxy)butyl)carbamate (500 mg) from step 2 in DCM was added trifluoroacetic acid (1 mL) at 0 °C and the resulting mixture was stirred at rt for 1 h. After completion of the reaction, the mixture was concentrated under reduced pressure to give a residue. The residue was triturated with EA (5 mL) to give intermediate 25 , 3-(4-(4-aminobutyloxy)phenyl)piperidine-2,6-dione (0.475 g, 95%) as TFA salt. LCMS (ESI ⁺ ) m/z 277.48 [M+H] ⁺ . Intermediate 26 3-(4-(4-((1-(4-aminophenyl)piperidin-4-yl)amino)butoxy)phenyl)piperidine-2,6-dione (Figure 27)

Intermediate 26 was prepared by following the same procedure described for intermediate 14 , using intermediate 25 (TFA salt, 550 mg, 1.463 mmol) instead of intermediate 13 to react with 1-(4-nitrophenyl)piperidin-4-one to provide intermediate 26 , 3-(4-(4-((1-(4-aminophenyl)piperidin-4-yl)amino)butoxy)phenyl)piperidine-2,6-dione (0.400 g, 57% and 88% for two steps).

Analytical data of step 1 product: LCMS (ESI ⁺ ) m/z 481.67 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.79 (s, 1H, NH), 8.05 (d, J = 9.4 Hz, 2H), 7.13 (d, J = 8.6 Hz, 2H), 7.06 (d, J = 9.4 Hz, 2H), 6.89 (d, J = 8.6 Hz, 2H), 4.15 - 4.02 (m, 2H), 3.98 (t, J = 6.2 Hz, 2H), 3.78 (dd, J = 11.2, 4.8 Hz, 1H), 3.14 - 3.02 (m, 3H), 2.91 - 2.79 (m, 2H), 2.70 - 2.60 (m, 1H), 2.55 - 2.44 (m, 1H), 2.22 - 2.10 (m, 1H), 2.04 - 1.94 (m, 3H), 1.82 - 1.72 (m, 2H), 1.72 - 1.59 (m, 2H), 1.49 - 1.35 (m, 2H).

Analytical data of intermediate 26 : LCMS (ESI ^- ) m/z 449.48 [MH] ^- . Intermediate 27 3-[4-[4-(4-aminophenyl)piperidin -1-yl]phenyl]piperidin-2,6-dione (Figure 28)

Step 1: To a solution of [4-(2,6-dibenzyloxy-3-pyridyl)phenyl]boronic acid (1 g, 2.43 mmol) in DCM (20 mL) at 25 °C was added N-(4-piperidinyl)phenyl To the reaction mixture was added tributyl 1-(2-(4-(4-ylphenyl)carbamate (404.6 mg, 1.46 mmol), Cu(OAc) ₂ (441.6 mg, 2.43 mmol), and TEA (984.2 mg, 9.73 mmol). The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO ₄ . The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 30:1) to give N-[4-[4-[4-(2,6-dibenzyloxy-3-pyridinyl)phenyl]piperidinyl]-4-thiazolinyl]-1 ... -1-yl]phenyl]carbamic acid tributyl ester (400.3 mg, 12.19% yield, 47.62% purity). LCMS (ESI ⁺ ) m/z 643.4 [M+H] ⁺ .

Step 2: At 25°C, add N-[4-[4-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]piperidin To a solution of tributyl [4-[4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl]carbamate (400.3 mg, 296.3 µmol) in THF (10 mL) was added Pd/C (6.28 mg, 29.634 µmol, 50% purity). The reaction was stirred at 25 °C under _H2 atmosphere (15 psi) for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was filtered and the filter cake was washed with THF (30 mL). The collected filtrate was concentrated to give N-[4-[4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl]carbamate as a yellow solid. -1-yl]phenyl]carbamic acid tributyl ester (160.0 mg, 99.43% yield, 67.11% purity). LCMS (ESI ⁺ ) m/z 465.3 [M+H] ⁺ .

Step 3: Add N-[4-[4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl] to the mixture at 25°C. To a solution of tributyl [4-(4-aminophenyl)piperidinamide (160.0 mg, 231.14 µmol) in DCM (4 mL) was added TFA (0.4 mL). The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The reaction was concentrated under reduced pressure to give 3-[4-[4-(4-aminophenyl)piperidinamide as a yellow oil. 4-[4-[2-(4-aminophenyl)ethyl]piperidin-2,6-dione ( Intermediate 27 ) (100.0 mg, 97.18% yield, 81.86% purity). LCMS (ESI ⁺ ) m/z 365.2 [M+H] ⁺ . Intermediate 28 3-[4-[4-[2-(4-aminophenyl)ethyl]piperidin-2,6-dione -1-yl]phenyl]piperidin-2,6-dione (Figure 29)

Step 1: To a solution of [4-(2,6-dibenzyloxy-3-pyridyl)phenyl]boronic acid (3.0 g, 7.29 mmol) in DCM (30 mL) at 20 °C was added piperidine. -1-carboxylic acid tributyl ester (1.4 g, 7.29 mmol), Cu(OAc) ₂ (1.32 g, 7.29 mmol), and TEA (2.9 g, 29.18 mmol). The reaction was stirred at 20 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (30 mL) and extracted with DCM (3 × 30 mL). The combined organic layers were washed with brine (3 × 20 mL) and dried over Na ₂ SO _4. After filtration, the filtrate was concentrated to give the crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 20:1) to give 4-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]piperidin as a yellow solid. -1-carboxylic acid tributyl ester (0.7 g, 10.9% yield, 63.17% purity). LCMS (ESI ⁺ ) m/z 552.3 [M+H] ⁺ .

Step 2: Add 4-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]piperidin at 20°C. To a solution of tributyl 1-carboxylate (0.7 g, 801.54 µmol) in THF (20 mL) was added Pd/C (85.3 mg, 80.15 µmol, 10% purity). The reaction was stirred at 20 °C under _H2 atmosphere (15 psi) for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was filtered and the filter cake was washed with THF (30 mL). The collected filtrate was concentrated to give 4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl as a yellow solid. -1-carboxylic acid tributyl ester (0.4 g, 95.5% yield, 71.53% purity). LCMS (ESI ⁺ ) m/z 374.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H), 7.07 (d, J = 8.7 Hz, 2H), 6.91 (d, J = 8.7 Hz, 2H), 3.73 (dd, J = 11.1, 4.9 Hz, 1H), 3.50 - 3.41 (m, 4H), 3.12 - 3.02 (m, 4H), 2.63 (ddd, J = 17.1, 11.4, 5.2 Hz, 1H), 2.48 (br s, 1H), 2.20 - 2.08 (m, 1H), 2.05 - 1.96 (m, 1H), 1.42 (s, 9H).

Step 3: Add 4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl to 4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl at 0°C. To a solution of tributyl 1-carboxylate (0.4 g, 766.16 µmol) in DCM (10 mL) was added TFA (1 mL). The reaction was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The reaction was concentrated under reduced pressure to give 3-(4-piperidin-2-yl)-piperidin-1-yl as a yellow solid. -1-ylphenyl)piperidine-2,6-dione (0.25 g, 96.6% yield, 80.94% purity). LCMS (ESI ⁺ ) m/z 274.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.79 (s, 1H), 8.78 (br s, 1H), 7.11 (d, J = 8.5 Hz, 2H), 6.95 (d, J = 8.6 Hz, 2H), 3.76 (dd, J = 11.2, 4.9 Hz, 1H), 3.38 - 3.28 (m, 4H), 3.24 (br s, 4H), 2.64 (ddd, J = 17.2, 11.6, 5.3 Hz, 1H), 2.49 - 2.41 (m, 1H), 2.22 - 2.09 (m, 1H), 2.05 - 1.95 (m, 1H).

Step 4: At 25°C, 3-(4-piperidin To a solution of 1-(4-(2-oxoethyl)phenyl)piperidine-2,6-dione (0.25 g, 740.32 µmol) and tributyl N-[4-(2-oxoethyl)phenyl]carbamate (209.02 mg, 888.38 µmol) in DCM (6 mL) was added DIEA (191.4 mg, 1.48 mmol) and AcOH (44.5 mg, 740.32 µmol, 42.34 µL). The reaction was stirred at 25 °C for 2 h. NaBH(OAc) ₃ (313.8 mg, 1.48 mmol) was added to the mixture, and the mixture was stirred at 20 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. After filtration, the filtrate was concentrated under reduced pressure to give N-[4-[2-[4-[4-(2,6-dioxol-3-piperidinyl)phenyl]piperidinyl]-1- ... -1-yl]ethyl]phenyl]carbamic acid tributyl ester (0.3 g, 44.0% yield, 53.52% purity). LCMS (ESI ⁺ ) m/z 493.3 [M+H] ⁺ .

Step 5: Add N-[4-[2-[4-[4-(2,6-dioxo-3-piperidinyl)phenyl]piperidinyl] to the mixture at 0°C. To a solution of tert-butyl [4-[4-[2-(4-aminophenyl)ethyl]phenyl]carbamate (0.3 g, 325.94 µmol) in DCM (6 mL) was added TFA (0.6 mL). The reaction was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The reaction was concentrated under reduced pressure to give a residue. The residue was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to provide 3-[4-[4-[2-(4-aminophenyl)ethyl]piperidin as a yellow solid. -1-yl]phenyl]piperidine-2,6-dione ( Intermediate 28 ) (0.1 g, 74.0% yield, 94.69% purity). LCMS (ESI ⁺ ) m/z 393.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H), 7.04 (d, J = 8.8 Hz, 2H), 6.88 (dd, J = 8.4, 6.9 Hz, 4H), 6.52 - 6.44 (m, 2H), 4.81 (s, 2H), 3.72 (dd, J = 10.9, 4.9 Hz, 1H), 3.15 - 3.06 (m, 4H), 2.68 - 2.58 (m, 2H), 2.57 - 2.53 (m, 4H), 2.49 - 2.41 (m, 4H), 2.19 - 2.08 (m, 1H), 2.10 - 2.19 (m, 1H), 2. 1H). Intermediate 29 3-[[4-[4-(4-aminophenyl)piperidin -1-yl]cyclohexyl]amino]piperidine-2,6-dione (Figure 30)

Step 1: To a solution of tributyl N-(4-hydroxycyclohexyl)carbamate (500.0 mg, 2.34 mmol) in DCM (10 mL) at 25 °C was added 1-(4-nitrophenyl)piperidin (485.83 mg, 2.34 mmol) and NaBH(OAc) ₃ (993.7 mg, 4.69 mmol). The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 3:1) to give N-[4-[4-(4-nitrophenyl)piperidinyl]-4-nitrophenyl ... -1-yl]cyclohexyl]carbamic acid tributyl ester (400.0 mg, 42.18% yield, 100.00% purity). LCMS (ESI ⁺ ) m/z 405.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.10 - 8.00 (m, 2H), 7.06 - 6.98 (m, 2H), 3.42 (br d, J = 4.4 Hz, 4H), 3.32 (br d, J = 2.1 Hz, 1H), 2.59 (br s, 4H), 2.27 - 2.21 (m, 1H), 1.75 - 1.58 (m, 4H), 1.50 - 1.40 (m, 4H), 1.38 (t, J = 4.9 Hz, 9H).

Step 2: N-[4-[4-(4-nitrophenyl)piperidin -1-yl]cyclohexyl]carbamic acid tributyl ester (400.0 mg, 988.87 µmol, 100.00% purity) in HCl/dihydrochloric acid The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and a major product with the desired MS was detected. The mixture was concentrated under reduced pressure to give 4-[4-(4-nitrophenyl)piperidinyl]-4-nitrophenyl]-4-nitrophenyl]-piperidinyl acetate as a yellow solid. -1-yl]cyclohexylamine (300.2 mg, 99.67% yield, 84.78% purity). LCMS (ESI ⁺ ) m/z 305.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.11 (d, J = 9.3 Hz, 2H), 7.21 - 7.04 (m, 2H), 4.26 - 4.13 (m, 2H), 3.60 (br s, 1H), 3.53 (br s, 2H), 3.37 (br s, 2H), 3.29 - 3.10 (m, 2H), 2.62 - 2.53 (m, 2H), 2.29 - 2.05 (m, 2H), 2.04 - 1.94 (m, 4H), 1.77 - 1.56 (m, 2H), 1.49 - 1.36 (m, 1H).

Step 3: At 25°C, 4-[4-(4-nitrophenyl)piperidin To a solution of [0367]-1-yl]cyclohexylamine (300.2 mg, 835.58 µmol, 84.78% purity) in DMF (8 mL) was added 3-bromopiperidine-2,6-dione (240.6 mg, 1.25 mmol) and DIEA (539.9 mg, 4.18 mmol). The reaction was stirred at 80 °C for 12 h. LCMS showed that the reaction was complete and the desired compound was detected. The mixture was diluted with water (10 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. After filtration, the filtrate was concentrated under reduced pressure to give a residue. The residue was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to provide 3-[[4-[4-(4-nitrophenyl)piperidinyl]pyrrolidone as a yellow solid. -1-yl]cyclohexyl]amino]piperidine-2,6-dione (150.3 mg, 41.02% yield, 94.94% purity). LCMS (ESI ⁺ ) m/z 416.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.85 - 10.48 (m, 1H), 8.05 (d, J = 9.5 Hz, 2H), 7.08 - 6.96 (m, 2H), 3.43 (br d, J = 3.9 Hz, 4H), 3.40 (br d, J = 4.9 Hz, 2H), 2.81 (br s, 1H), 2.58 (br d, J = 4.6 Hz, 4H), 2.54 (br d, J = 4.9 Hz, 2H), 2.22 (br s, 1H), 2.04 - 1.95 (m, 1H), 1.75 - 1.68 (m, 1H), 1.65 (br d, J = 9.0 Hz, 4H), 1.53 - 1.39 (m, 4H).

Step 4: Add 3-[[4-[4-(4-nitrophenyl)piperidin at 25°C To a solution of [[4-[(4-aminophenyl)piperidin-2,6-dione (150.3 mg, 342.76 µmol, 94.94% purity) in THF (2 mL) was added Pd/C (5.7 mg, 34.28 µmol, 30% purity). The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was filtered and the filter cake was washed with THF (10 mL). The collected filtrate was concentrated to give 3-[[4-[4-(4-aminophenyl)piperidin-2,6-dione as a yellow solid. -1-yl]cyclohexyl]amino]piperidine-2,6-dione ( Intermediate 29 ) (100.0 mg, 53.13% yield, 70.20% purity). LCMS (ESI ⁺ ) m/z 386.2 [M+H] ⁺ . Intermediate 30 4-[4-(4-oxo-1-piperidinyl)phenyl]piperidine-2,6-dione (Figure 31)

Step 1: To a solution of 4-bromobenzaldehyde (5 g, 27.02 mmol) in ethyl 3-oxobutyrate (EAA) (7.74 g, 59.45 mmol) was added piperidine (1 mL) dropwise at 0 ^° C. Then, the mixture was stirred at 20 ^° C for 3 h. The precipitated solid was filtered and triturated with cold EtOH to give diethyl 2,4-diethylyl-3-(4-bromophenyl)pentanedioate (5 g, 11.7 mmol. 43.2%) as a white solid. Then, the crude solid was added to an aqueous solution of KOH (20 M, 50 mL). The mixture was stirred at 80 ^° C for 3 h. LCMS showed the formation of the desired product. After cooling to rt, concentrated HCl was slowly added to the mixture to adjust the pH to 3. The formed solid was filtered and washed with water to give 3-(4-bromophenyl)pentanedioic acid (3.9 g, 13.58 mmol, 50.26% yield) as a white solid. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 12.10 (br s, 2H), 7.47 (d, J = 8.4 Hz, 2H), 7.27 - 7.20 (m, 2H), 3.52 - 3.19 (m, 1H), 2.73 - 2.58 (m, 2H), 2.57 - 2.52 (m, 1H), 2.50 - 2.47 (m, 1H).

Step 2: 3-(4-Bromophenyl)pentanedioic acid (2.8 g, 9.75 mmol) and urea (1.46 g, 24.38 mmol) were mixed together and stirred at 160 ^° C for 3 h. LCMS showed the formation of the desired product. Then, the mixture was cooled to rt. The obtained solid was dissolved in EA and washed with water (3x). The organic layer was concentrated under reduced pressure to give 4-(4-bromophenyl)piperidine-2,6-dione (1 g, 3.73 mmol, 38.25% yield) as a brown solid. LCMS (ESI ⁺ ) m/z 268.0 (M+H) ⁺ .

Step 3: 4-(4-bromophenyl)piperidin-2,6-dione (500 mg, 1.31 mmol) was reacted with 1,4-dione. - 8-Azaspiro[4.5]decane (373.84 mg, 2.61 mmol, 334.68 µL) in di To a solution of 1,3-dichloro-2H-imidazol-1-ium-2-ylidene in 1,2-dioxane (10 mL) was added Cs ₂ CO ₃ (1.28 g, 3.92 mmol); 1,3-bis[2,6-bis(1-propylbutyl)phenyl]-4,5-dichloro-2H-imidazol-1-ium-2-ylidene; 3-chloropyridine; dichloropalladium (126.99 mg, 130.55 µmol). The mixture was then stirred at 100 °C under N ₂ protection for 5 h. Another batch was set up using the same procedure. LCMS showed the formation of the desired product. The mixture was extracted with EA (3 × 100 mL) and washed with saturated aqueous NH ₄ Cl solution. Then, the organic layer was dried over Na ₂ SO ₄ , filtered, and concentrated under reduced pressure to give a crude residue, which was further purified by passing through a silica column with an eluent of EA:PE = 1:1. 4-[4-(1,4-dihydro-1-yl)-1-nitropropene was obtained as a white solid. 3-(4-(4-nitro-8-yl)-1-piperidine-2,6-dione) (230 mg, 696.17 µmol, 53.33% yield). LCMS (ESI ⁺ ) 331 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.81 (br s, 1H), 7.01 (d, J = 8.7 Hz, 2H), 6.85 (d, J = 8.8 Hz, 2H), 3.92 (s, 4H), 3.33 - 3.21 (m, 5H), 2.89 - 2.76 (m, 2H), 2.70 - 2.55 (m, 2H), 1.86 - 1.69 (m, 4H).

Step 4: To 4-[4-(1,4- A solution of 4-[4-(4-oxo-1-piperidinyl)phenyl]piperidine-2,6-dione (230 mg, 302.68 µmol) in formic acid (2.3 mL) was stirred at 90 °C. LCMS showed the formation of the desired product. The reaction was washed with saturated aqueous NH ₄ Cl solution and extracted by EA (2 × 20 mL). The organic layers were combined and concentrated by reduced pressure. The crude residue was purified by preparative TLC using pure EA. 4-[4-(4-oxo-1-piperidinyl)phenyl]piperidine-2,6-dione (80 mg, 139.70 µmol, 46.15% yield) was formed as a white solid. ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.75 (br s, 1H), 7.07 (d, J = 8.7 Hz, 2H), 6.89 (d, J = 8.7 Hz, 2H), 3.54 (t, J = 6.1 Hz, 4H), 3.37 - 3.23 (m, 1H), 2.93 - 2.76 (m, 2H), 2.66 (dd, J = 11.4, 17.4 Hz, 2H), 2.49 (t, J = 6.1 Hz, 4H). Intermediate 31 2-allyl-6-[4-[4-(aminomethyl)-1-piperidinyl]anilino]-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one (Figure 32)

Step 1: To a solution of tert-butyl (piperidin-4-ylmethyl)carbamate (10 g, 70.87 mmol) and 1-fluoro-4-nitrobenzene (18.23 g, 85.05 mmol) in DMF (20 mL) was added DIEA (18.32 g, 141.74 mmol). The mixture was stirred at 60 °C for 12 h. LCMS showed one major peak with the desired MS detected. The reaction was added to water (50 mL) and the mixture was filtered. The filter cake was collected by suction filtration and dried in vacuo to give tert-butyl ((1-(4-nitrophenyl)piperidin-4-yl)methyl)carbamate (23 g, 68.58 mmol, 96.76% yield) as a yellow solid. LCMS (ESI ⁺ ) m/z 336.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.03 (d, J = 9.1 Hz, 2H), 7.00 (br d, J = 9.3 Hz, 2H), 6.91 (br t, J = 5.4 Hz, 1H), 4.04 (br d, J = 13.3 Hz, 2H), 2.95 (br t, J = 12.4 Hz, 2H), 2.84 (br t, J = 5.9 Hz, 2H), 1.76 - 1.62 (m, 3H), 1.38 (s, 9H), 1.13 (q, J = 11.3 Hz, 2H).

Step 2: A solution of tributyl ((1-(4-nitrophenyl)piperidin-4-yl)methyl)carbamate (23 g, 68.58 mmol) in HCl/EtOAc (4 M, 30 mL) was stirred at 25 °C for 2 h. LCMS showed that the starting material was consumed and a new spot was detected. The mixture was concentrated at 40 °C under reduced pressure to give crude 1-(4-nitrophenyl)piperidin-4-yl)methanamine (16 g, 99.17% yield) as a yellow solid, which was used in the next step without further purification. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.25 (br s, 3H), 8.06 - 7.99 (m, 2H), 7.72 (br s, 2H), 7.07 - 7.00 (m, 2H), 4.07 (br d, J = 13.4 Hz, 2H), 3.03 - 2.90 (m, 2H), 2.71 (quin, J = 5.9 Hz, 2H), 2.00 - 1.90 (m, 1H), 1.85 (br d, J = 13.1 Hz, 2H), 1.22 (dq, J = 3.8, 12.2 Hz, 2H).

Step 3: To a solution of (1-(4-nitrophenyl)piperidin-4-yl)methanamine (16 g, 68.00 mmol) and TFAA (21.42 g, 102.01 mmol) in DCM (200 mL) was added TEA (20.64 g, 204.01 mmol). The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The reaction was directly purified without workup. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:1 to 2:1) to give 2,2,2-trifluoro-N-((1-(4-nitrophenyl)piperidin-4-yl)methyl)acetamide (22 g, 89.48% yield, 91.633% purity) as a white solid. LCMS (ESI ⁺ ) m/z 332.1 [M+H] ⁺ .

Step 4: To a solution of 2,2,2-trifluoro-N-((1-(4-nitrophenyl)piperidin-4-yl)methyl)acetamide (22 g, 66.41 mmol) in THF (220 mL) was added Pd/C (141.34 g, 132.81 mmol, 10% purity) at 20 °C. The mixture was stirred at 20 °C for 12 h. LCMS showed one major peak with the desired MS detected. The reaction was filtered and the filter cake was washed with THF (200 mL). The combined filtrate was concentrated to give a crude product, which was purified by column chromatography on silica gel (eluted with THF:EA = 1:100 to 3:1) to give N-((1-(4-aminophenyl)piperidin-4-yl)methyl)-2,2,2-trifluoroacetamide (13 g, 35.34% yield, 54.4% purity) as a brown solid. LCMS (ESI ⁺ ) m/z 302.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 9.50 (br t, J = 5.4 Hz, 1H), 7.05 - 6.73 (m, 2H), 6.71 - 6.39 (m, 2H), 6.36 - 5.80 (m, 2H), 3.41 (br d, J = 4.6 Hz, 2H), 3.14 (br t, J = 6.1 Hz, 2H), 2.62 (br s, 2H), 1.70 (br s, 3H), 1.30 (br d, J = 11.7 Hz, 2H).

Step 5: To a solution of (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-(methylthio)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one (5 g, 13.04 mmol) in toluene (50 mL) at 20 °C was added m-CPBA (5.29 g, 26.08 mmol, 85% purity). The reaction was stirred at 25 °C for 2 h, then a solution of N-((1-(4-aminophenyl)piperidin-4-yl)methyl)-2,2,2-trifluoroacetamide (4.71 g, 15.65 mmol) and DIEA (8.43 g, 65.19 mmol) in DMF (50 mL) was added dropwise to the reaction at 0 °C. The reaction was stirred at 25 °C for 12 h. An additional reaction was set up as above, and the reactions were combined for work-up. The reaction was poured into water (100 mL) and extracted with EA (200 mL). The organic layer _was dried over _Na2SO4 and filtered. The filtrate was concentrated to give a crude product, which was purified by column chromatography on silica gel (eluted with EA) to give (R)-N-((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)-2,2,2-trifluoroacetamide (11 g, 17.28 mmol, 66.25% yield) as a yellow solid. ¹ H NMR (400 MHz, CDCl ₃ ) δ 8.81 (s, 1H), 7.73 - 7.67 (m, 2H), 7.46 (br d, J = 8.4 Hz, 2H), 6.92 (br d, J = 8.9 Hz, 2H), 6.49 (br s, 1H), 5.70 (tdd, J = 6.2, 10.4, 16.8 Hz, 1H), 5.03 (d, J = 10.3 Hz, 1H), 4.93 (d, J = 17.1 Hz, 1H), 4.90 - 4.80 (m, 1H), 4.78 - 4.64 (m, 1H), 3.68 (br d, J = 12.3 Hz, 3H), 3.37 (t, J = 6.4 Hz, 2H), 3.14 - 2.98 (m, 1H), 2.95 - 2.82 (m, 1H), 2.72 (br t, J = 11.4 Hz, 2H), 2.40 (ddd, J = 4.5, 8.6, 13.4 Hz, 2H), 2.29 - 2.20 (m, 1H), 2.05 - 1.97 (m, 1H), 1.82 - 1.84 (m, 1H), 1.83 - 1.99 (m, 1H), 1.65 - 1.70 (m, 1H), 1.84 (dq, J = 3.7, 12.0 Hz, 2H ), 7.4 Hz, 3H).

Step 6: To a solution of N-[[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]methyl]-2,2,2-trifluoro- _acetamide (10 g, 15.71 mmol) in MeOH (300 mL) was added _K2CO3 (21.71 g, 157.07 mmol). The reaction was stirred at 30 °C for 48 h. LCMS showed the reaction was complete. The reaction was diluted with water (300 mL) and extracted with DCM (5 x 300 mL). The organic layer was dried _{over Na2SO4} and filtered. The filtrate was concentrated to give 2-allyl-6-[4-[4-(aminomethyl)-1-piperidinyl]anilino]-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one ( Intermediate 31 ) (9 g, 14.98 mmol, 95.38% yield, 90% purity) as a yellow solid. LCMS (ESI ⁺ ) m/z 541.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.29 - 9.94 (m, 1H), 8.82 (s, 1H), 7.94 (br d, J = 7.1 Hz, 1H), 7.70 (d, J = 8.3 Hz, 1H), 7.57 (br s, 2H), 6.92 (br d, J = 9.0 Hz, 2H), 5.67 (tdd, J = 6.0, 10.6, 16.8 Hz, 1H), 5.08 (br s, 1H), 5.00 (d, J = 10.3 Hz, 1H), 4.86 (br d, J = 17.0 Hz, 1H), 4.80 - 4.71 (m, 3H), 2.47 - 2.54 (m, 2H), 2.23 (ddd, J = 5.8, 8.2, 13.4 Hz, 1H), 2.14 - 2.71 (m, 1H), 1.96 (br dd, J = 7.5, 13.6 Hz, 1H), 1.85 - 1.81 (m, 3H), 1.59 - 1.33 (m, 3H), 1.65 - 1.71 (m, 4H) , 1.45 - 1.63 (m, 4H) , 1.20 - 1.41 ( m , 4H), 1.24 - 1.83 (m, 4H), 1.42 - 1.40 (m, 4H), 1. 1H), 1.38 - 1.28 (m, 1H), 1.28 - 1.13 (m, 2H), 0.88 (t, J = 7.4 Hz, 3H). Intermediate 33 3-((3-(4-aminopiperidin-1-yl)phenyl)amino)piperidine-2,6-dione (Figure 33)

Step 1: To a solution of 1-bromo-3-nitrobenzene (10.0 g, 40.16 mmol) in toluene (200 mL) was added BINAP (2.5 g, 4.02 mmol), Pd(OAc) ₂ (901.6 mg, 4.02 mmol), tributyl piperidin-4-ylcarbamate (8.1 g, 40.16 mmol), and _Cs2CO3 (26.17 g, 80.32 mmol) at 25 °C. The reaction was stirred at 100 °C for 12 _h . LCMS showed that the starting material was consumed and the desired product was detected. The reaction was concentrated under reduced pressure to give the product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 25:1) to give tri-butyl N-(1-(3-nitrophenyl)piperidin-4-yl)carbamate (6.0 g, 40.8% yield, 87.87% purity) as a yellow solid. LCMS (ESI ⁺ ) m/z 322.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 7.62 (t, J = 2.2 Hz, 1H), 7.53 (dd, J = 7.8, 1.0 Hz, 1H), 7.44 (t, J = 8.1 Hz, 1H), 7.40 (d, J = 1.5 Hz, 1H), 6.87 (br d, J = 7.8 Hz, 1H), 3.77 (br d, J = 13.2 Hz, 2H), 3.45 (br dd, J = 8.4, 1.9 Hz, 1H), 2.92 - 2.84 (m, 2H), 1.81 (br d, J = 11.0 Hz, 2H), 1.50 - 1.42 (m, 2H), 1.39 (s, 9H).

Step 2: To a solution of tert-butyl N-[1-(3-nitrophenyl)-4-piperidinyl]carbamate (6.0 g, 16.41 mmol) in THF (30 mL) at 25 °C was added Pd/C (17.4 g, 16.41 mmol, 30% purity). The reaction was stirred at 25 °C for 12 h. TLC showed that the starting material was consumed and a new spot was detected. The mixture was filtered and the filter cake was washed with THF (50 mL). The collected filtrate was concentrated to give tert-butyl N-[1-(3-aminophenyl)-4-piperidinyl]carbamate (4.0 g, 41.84% yield) as a yellow solid. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ = 6.90 - 6.78 (m, 1H), 6.73 (br d, J = 7.6 Hz, 1H), 6.17 - 6.07 (m, 1H), 5.99 (dd, J = 7.7, 1.2 Hz, 1H), 4.81 (s, 1H), 3.60 (t, J = 6.4 Hz, 1H), 3.51 (br d, J = 12.7 Hz, 1H), 3.40 - 3.17 (m, 2H), 2.86 (br d, J = 12.3 Hz, 1H), 2.67 - 2.58 (m, 1H), 2.39 (dt, J = 12.0, 2.0 Hz, 1H), 1.80 - 1.70 (m, 2H), 1.61 (br d, J = 11.0 Hz, 1H), 1.38 (d, J = 5.9 Hz, 9H), 1.26 - 1.12 (m, 1H).

Step 3: At 25°C, add tributyl (1-(3-aminophenyl)piperidin-4-yl)carbamate (4.0 g, 6.86 mmol) to distilled water. To a mixture of 4-nitropropane (40 mL), 3-bromopiperidine-2,6-dione (3.9 g, 20.59 mmol), DIEA (1.7 g, 13.73 mmol, 2.4 mL), and NaI (205.7 mg, 1.37 mmol) were added. The mixture was stirred at 60 °C for 12 h. LCMS showed that the reaction was complete and the desired compound was detected. The mixture was diluted with water (30 mL) and extracted with DCM (3 × 30 mL). The combined organic layers were washed with brine (3 × 30 mL) and dried over Na ₂ SO ₄ . After filtration, the filtrate was concentrated under reduced pressure to give tri-butyl (1-(3-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidin-4-yl)carbamate (1.5 g, 3.11 mmol, 45.3% yield) as a yellow solid. LCMS (ESI ⁺ ) m/z 403.2 [M+H] ⁺ .

Step 4: To a solution of tributyl (1-(3-((2,6-dioxopiperidin-3-yl)amino)phenyl)piperidin-4-yl)carbamate (1.5 g, 3.11 mmol) in DCM (8 mL) at 25 °C was added TFA (0.8 mL). The reaction was stirred at 25 °C for 12 h. LCMS showed that the starting material was consumed and a major product with the desired MS was detected. The mixture was concentrated under reduced pressure to give 3-((3-(4-aminopiperidin-1-yl)phenyl)amino)piperidine-2,6-dione ( intermediate 33 ) (0.4 g, 19.5% yield, 43.96% purity) as a yellow solid. LCMS (ESI ⁺ ) m/z 303.2 [M+H] ⁺ . Intermediate 34 2-Allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-[4-(4-oxo-1-piperidinyl)anilino]pyrazolo[3,4-d]pyrimidin-3-one (Figure 34)

Step 1: A solution of tributyl (4-(4-oxopiperidin-1-yl)phenyl)carbamate (1.00 g, 3.44 mmol) in DCM (10 mL) and TFA (1 mL) at 25 °C. The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated under reduced pressure to give 1-(4-aminophenyl)piperidin-4-one (0.50 g, 76.31% yield) as a yellow solid. LCMS (ESI ⁺ ) m/z 191.2 [M+H] ⁺ .

Step 2: To a solution of 1-(4-aminophenyl)piperidin-4-one (0.50 g, 2.63 mmol) in toluene (3 mL) at 25 °C was added DIEA (622.15 mg, 4.81 mmol) and 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3-one (Huang et al., J. Med. Chem. (2021) 64:13004-13024, 1.00 g, 2.41 mmol). The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was diluted with water (10 mL) and extracted with EA (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:0 to 20:1) to give 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-[4-(4-oxo-1-piperidinyl)anilino]pyrazolo[3,4-d]pyrimidin-3-one (0.30 g, 23.71% yield) as a yellow solid. LCMS (ESI ⁺ ) m/z 526.2 [M+H] ⁺ . Intermediate 35 3-[4-(2-aminoethylamino)phenyl]piperidine-2,6-dione (Figure 35)

Step 1: To a solution of 3-(4-aminophenyl)piperidine-2,6-dione (0.60 g, 1.72 mmol) and tributyl N-(2-bromoethyl)carbamate (384.8 mg, 1.72 mmol) in DMF (12.0 mL) at 20 °C was added DIEA (443.9 mg, 3.43 mmol). The mixture was stirred at 80 °C under _N2 for 12 h. LCMS showed complete consumption of the starting material. The mixture was concentrated in vacuo to give a residue. The residue was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to provide tributyl N-[2-[4-(2,6-dioxo-3-piperidinyl)anilino]ethyl]carbamate (60.0 mg, 9.38% yield) as a white solid. LCMS (ESI ⁺ ) m/z 348.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.72 (s, 1H), 6.98 - 6.78 (m, 3H), 6.52 (d, J = 8.5 Hz, 2H), 5.54 (br t, J = 5.2 Hz, 1H), 3.64 (dd, J = 10.5, 4.9 Hz, 1H), 3.05 (td, J = 11.0, 5.5 Hz, 4H), 2.66 - 2.55 (m, 1H), 2.47 - 2.40 (m, 1H), 2.14 - 2.05 (m, 1H), 2.05 - 1.94 (m, 1H), 1.38 (s, 9H).

Step 2: A mixture of tributyl N-[2-[4-(2,6-dioxo-3-piperidinyl)anilino]ethyl]carbamate (60.0 mg, 161.15 µmol, 93.31% purity) in DCM (2.0 mL) and TFA (0.2 mL) was stirred at 20 °C for 2 h. TLC showed that the starting material was completely consumed. The mixture was concentrated in vacuo to give 3-[4-(2-aminoethylamino)phenyl]piperidine-2,6-dione (TFA salt, 42.0 mg, 70.61% yield) as a yellow oil. Intermediate 36 2-allyl-6-[4-(4-amino-1-piperidinyl)anilino]-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one (Figure 36)

Step 1: To a solution of N-[1-(4-aminophenyl)-4-piperidinyl]-2,2,2-trifluoro-acetamide (829.76 mg, 2.89 mmol) and 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3-one (1.00 g, 2.41 mmol) in DMF (10 mL) was added DIEA (622.16 mg, 4.81 mmol). The reaction was stirred at 20 °C for 12 h. LCMS showed the reaction was complete. The mixture was diluted with water (20 mL) and extracted with EA (3 × 30 mL). The organic layer was dried _{over Na2SO4} and filtered. The filtrate was concentrated under reduced pressure to give N-[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxopyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]-2,2,2-trifluoro-acetamide (1.10 g, 73.4% yield) as a yellow solid. LCMS (ESI ⁺ ) m/z 623.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.12 (br s, 1H), 9.35 (br d, J = 7.8 Hz, 1H), 8.82 (s, 1H), 7.93 (br d, J = 7.3 Hz, 1H), 7.76 - 7.64 (m, 1H), 7.58 (br s, 2H), 6.94 (br d, J = 9.0 Hz, 2H), 5.71 - 5.61 (m, 1H), 5.04 (s, 1H), 4.99 (dd, J = 10.3, 1.0 Hz, 1H), 4.92 - 4.82 (m, 1H), 4.77 (br d, J = 14.4 Hz, 3H), 4.57 (br dd, J = 15.4, 5.6 Hz, 1H), 3.69 (br d, J = 12.5 Hz, 2H), 3.04 - 2.91 (m, 1H), 2.83 - 2.65 (m, 3H), 2.26 - 2.16 (m, 1H), 2.07 - 2.00 (m, 2H), 1.94 - 1.83 (m, 2H), 1.78 - 1.61 (m, 3H), 0.87 (t, J = 7.4 Hz, 3H).

Step 2: To a solution of N-[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]-2,2,2-trifluoro- _acetamide (1.00 g, 1.61 mmol) in MeOH (50 mL) was added _K2CO3 (1.78 g, 12.85 mmol). The reaction was stirred at 20 °C for 12 h. LCMS showed the reaction was complete. The mixture was concentrated under reduced pressure to give 2-allyl-6-[4-(4-amino-1-piperidinyl)anilino]-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one (Intermediate 36 ) (0.96 g, 90.8% yield) as a white solid. LCMS (ESI ⁺ ) m/z 527.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.22 - 9.95 (m, 1H), 8.87 - 8.75 (m, 1H), 7.93 (br d, J = 7.3 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.64 - 7.44 (m, 2H), 6.91 (br d, J = 8.9 Hz, 2H), 5.77 - 5.56 (m, 1H), 5.14 - 5.03 (m, 1H), 5.00 (br d, J = 10.1 Hz, 1H), 4.86 (br d, J = 17.2 Hz, 1H), 4.75 (br d, J = 12.8 Hz, 1H), 4.57 (br dd, J = 15.6, 5.6 Hz, 1H), 3.62 - 3.44 (m, 2H), 3.30 (br s, 2H), 3.09 - 2.90 (m, 2H), 2.83 - 2.71 (m, 2H), 2.71 - 2.60 (m, 2H), 2.26 - 2.12 (m, 1H), 2.07 - 1.99 (m, 1H), 1.95 - 1.83 (m, 1H), 1.83 - 1.63 (m, 3H), 1.40 - 1.28 (m, 1H), 0.87 (br t, J = 7.4 Hz, 3H). Intermediate 37 4-(3-(4-oxo-piperidin-1-yl)phenyl)piperidine-2,6-dione (Figure 37)

Step 1: 4-(3-bromophenyl)piperidin-2,6-dione (1 g, 3.73 mmol) and 1,4-dimethoxybenzyl alcohol were added at 25 °C under _N2. -8-Azaspiro[4.5]decane (194.96 mg, 1.36 mmol) in di To a solution of 4-nitropropane (20 mL) was added Cs ₂ CO ₃ (1.33 g, 4.08 mmol) and 1,3-bis[2,6-bis(1-propylbutyl)phenyl]-4,5-dichloro-imidazol-2-ylidene]-dichloro-(3-chloropyridin-1-ium-1-yl)palladium (92.79 mg, 136.16 µmol). The reaction was stirred at 70 °C under N ₂ for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The reaction was diluted with water (100 mL) and extracted with EA (100 mL). The organic layer was dried over Na ₂ SO _4. After filtration, the filtrate was concentrated under reduced pressure to give the crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 99:1 to 10:90) to give 4-(3-(1,4-dihydro-1-yl)-1-nitropropene as a yellow solid. -8-Azaspiro[4.5]dec-8-yl)phenyl)piperidine-2,6-dione (0.16 g, 484.29 µmol, 35.57% yield). LCMS (ESI ⁺ ) m/z 331.2 [M+H] ⁺ .

Step 2: 4-(3-(1,4- A solution of 2-(4-(4-(2-nitro-8-nitro-1-yl)phenyl)piperidine-2,6-dione (0.15 g, 454.03 µmol) in HCOOH (1.5 mL) was stirred at 90 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The reaction was cooled to 25 °C and quenched with saturated NaHCO ₃ solution. The resulting mixture was extracted with EA (100 mL). The organic layer was dried over Na ₂ SO ₄ . After filtration, the filtrate was concentrated under reduced pressure to give 4-(3-(4-oxopiperidin-1-yl)phenyl)piperidine-2,6-dione ( intermediate 37 ) (0.11 g, 384.18 µmol, 84.62% yield), which was used in the next step without further purification. LCMS (ESI ⁺ ) m/z 287.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.83 (br s, 1H), 7.19 (t, J = 7.9 Hz, 1H), 6.98 (s, 1H), 6.89 (dd, J = 2.0, 8.1 Hz, 1H), 6.70 (d, J = 7.7 Hz, 1H), 3.60 (t, J = 5.9 Hz, 4H), 3.40 - 3.34 (m, 1H), 2.82 (dd, J = 11.4, 16.8 Hz, 2H), 2.66 (d, J = 4.3 Hz, 1H), 2.61 (d, J = 4.4 Hz, 1H), 2.40 (t, J = 5.9 Hz, 4H). Intermediate 38 4-[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin -1-yl]butyraldehyde (Figure 38)

₂ -allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-(4-piperidin-2-yl)-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl] ...6-(4-piperidin-2-yl)-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]- To a solution of 2-(4-(4-(4-nitrophenyl)pyrazolo[3,4-d]pyrimidin-3-one) ( intermediate 8 ) (0.1 g, 195.08 umol) in THF (5 mL) was added succinaldehyde (503.83 mg, 5.85 mmol) and NaBH(OAc) ₃ (82.69 mg, 390.16 umol) over 2 h. LCMS showed complete consumption of the starting material. The mixture was poured into H ₂ O (5 mL). The mixture was extracted with EA (3 × 5 mL). The organic phase was washed with brine (10 mL), dried over _{anhydrous Na2SO4} and concentrated in vacuo to give a residue which was purified by preparative TLC to provide 4-[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin-2-yl as a yellow solid. -1-yl]butanal (Intermediate 38 ) (0.082 g, 101.60 umol, 52.08% yield, 72.20% purity). LCMS (ESI ⁺ ) m/z 583.4 [M+H] ⁺ . Intermediate 40 3-[4-[4-[[4-(4-aminophenyl)piperidin -1-yl]methyl]-4-hydroxy-1-piperidinyl]anilino]piperidin-2,6-dione (Figure 39)

Step 1: To a mixture of tributyl 4-oxopiperidine-1-carboxylate (20.00 g, 100.38 mmol) in ACN (200 mL) at 20 °C, trimethylsulfonium iodide (26.51 g, 120.45 mmol) and KOH (8.45 g, 150.57 mmol) were added, and the mixture was stirred at 20 °C for 12 h. TLC (PE:EA = 1:1) showed complete consumption of the starting material. The mixture was poured into H ₂ O (150 mL). The mixture was extracted with EA (3 × 150 mL). The organic phase was washed with brine (150 mL), dried over anhydrous Na ₂ SO ₄ and concentrated in vacuo to give a residue . The residue was used in the next step without purification. 1-(4-nitrophenyl)piperidin was obtained as a yellow oil. (20.00 g, 46.71% yield). ¹ H NMR (400 MHz, DMSO-d ₆ ) ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 3.66 (br d, J = 12.5 Hz, 2H), 2.99 (br s, 2H), 2.89 - 2.54 (m, 2H), 1.55 - 1.42 (m, 4H), 1.38 (s, 9H).

Step 2: To tributyl N-(1-oxospiro[2.5]octan-6-yl)carbamate (10.00 g, 23.44 mmol, 50.00% purity) and 1-(4-nitrophenyl)piperidin To a solution of 4-hydroxy-4-((4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene (5.83 g, 28.13 mmol) in MeOH (100 mL) was added DIEA (9.09 g, 70.33 mmol, 12.25 mL). The reaction was stirred at 60 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 40:60) to give pure 4-hydroxy-4-((4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene (4-hydroxy-4-(4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene (4-hydroxy-4-(4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene (4-hydroxy-4-(4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene (4-hydroxy-4-(4-(4-nitrophenyl)piperidin-2-yl)-1-nitropropene) [0063] Tributyl 4-(4-(4-yl)methyl)piperidine-1-carboxylate (8.00 g, 81.15% yield) was obtained as a yellow oil. LCMS (ESI ⁺ ) m/z 421.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.04 (d, J = 9.4 Hz, 2H), 7.00 (d, J = 9.4 Hz, 2H), 4.27 (s, 1H), 3.60 (br d, J = 12.8 Hz, 2H), 3.47 - 3.38 (m, 4H), 3.10 (br s, 2H), 2.67 - 2.60 (m, 4H), 2.30 (s, 2H), 1.48 - 1.42 (m, 4H), 1.38 (s, 9H).

Step 3: Under _N2 atmosphere, 4-hydroxy-4-[[4-(4-nitrophenyl)piperidin To a solution of tributyl 4-[[4-(4-aminophenyl)piperidine-1-carboxylate (8.00 g, 19.02 mmol, 100% purity) in THF (160 mL) was added Pd/C (10%, 2.02 g). The mixture was degassed and purged with _H2 (3x). The mixture was stirred under _H2 (15 psi) at 20 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give 4-[[4-(4-aminophenyl)piperidine-1-carboxylic acid tributyl ester as a white solid. -1-yl]methyl]-4-hydroxy-piperidine-1-carboxylic acid tributyl ester (7.00 g, 88.02% yield). LCMS (ESI ⁺ ) m/z 391.1 [M+H] ⁺ .

Step 4: 4-[[4-(4-aminophenyl)piperidin To a solution of [3-(4-(4-(4-hydroxy-1-piperidine-1-carboxylic acid)-1-butyl]-4-hydroxy-piperidine-1-carboxylic acid tributyl ester (7.00 g, 16.75 mmol, 93.42% purity) in DCM (70 mL) was added TFAA (3.87 g, 18.42 mmol, 2.56 mL) and TEA (3.39 g, 33.49 mmol, 4.66 mL). The reaction was stirred at 20 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the product, which was used in the next step without further purification. 4-Hydroxy-4-[[4-[4-[(2,2,2-trifluoroacetyl)amino]phenyl]piperidin -1-yl]methyl]piperidine-1-carboxylic acid tributyl ester (6.00 g, 67.77% yield, 92.02% purity). LCMS (ESI ⁺ ) m/z 487.3 [M+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.92 (br s, 1H), 7.52 - 7.40 (m, 2H), 6.92 (d, J = 8.9 Hz, 2H), 4.03 - 3.83 (m, 2H), 3.37 - 3.06 (m, 6H), 2.90 (s, 3H), 2.74 - 2.68 (m, 1H), 2.61 - 2.28 (m, 2H), 1.62 (br s, 3H), 1.47 (s, 9H).

Step 5: 4-Hydroxy-4-[[4-[4-[(2,2,2-trifluoroacetyl)amino]phenyl]piperidin A mixture of tributyl]piperidine-1-carboxylate (6.00 g, 11.35 mmol, 92.02% purity) in TFA (60 mL) and DCM (6 mL) was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the product, which was used in the next step without further purification. 2,2,2-trifluoro-N-(4-(4-((4-hydroxypiperidin-4-yl)methyl)piperidin-1-carboxylate was obtained as a black solid. -1-yl)phenyl)acetamide (4.00 g, 85.65% yield). LCMS (ESI ⁺ ) m/z 387.2 [M+H] ⁺ .

Step 6: To 2,2,2-trifluoro-N-[4-[4-[(4-hydroxy-4-piperidinyl)methyl]piperidinyl To a solution of 1-fluoro-4-nitro-benzene (1.10 g, 7.80 mmol, 827.07 µL) in DMF (20 mL) was added DIEA (5.04 g, 38.98 mmol, 6.79 mL). The reaction was stirred at 80 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was poured into water (20 mL) and extracted with EA (3 × 20 mL). The combined organic layers were washed with brine (20 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure to give 2,2,2-trifluoro-N-[4-[4-[[4-hydroxy-1-(4-nitrophenyl)-4-piperidinyl]methyl]piperidinyl]methyl]piperidinyl as a white solid. -1-yl]phenyl]acetamide (2.00 g, 46.05% yield, 91.09% purity). LCMS (ESI ⁺ ) m/z 508.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 11.02 (s, 1H), 8.02 (d, J = 9.5 Hz, 2H), 7.48 (d, J = 8.9 Hz, 2H), 7.01 (d, J = 9.5 Hz, 2H), 6.93 (d, J = 9.0 Hz, 2H), 4.40 (s, 1H), 3.76 (br d, J = 13.2 Hz, 2H), 3.09 (br d, J = 4.2 Hz, 5H), 2.66 (br s, 4H), 2.34 (s, 2H), 1.61 (br d, J = 3.9 Hz, 4H).

Step 7: Reverse the reaction mixture of 2,2,2-trifluoro-N-[4-[4-[[4-hydroxy-1-(4-nitrophenyl)-4-piperidinyl]methyl]piperidinyl To a solution of 4-[[4-(4-aminophenyl)piperidinamide (2.00 g, 3.59 mmol) in MeOH (20 mL) was added K ₂ CO ₃ (992.24 mg, 7.18 mmol). The mixture was stirred at 20° C. for 2 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40° C. under reduced pressure to give 4-[[4-(4-aminophenyl)piperidinamide as a white solid. -1-yl]methyl]-1-(4-nitrophenyl)piperidin-4-ol (1.50 g, 36.12% yield). LCMS (ESI ⁺ ) m/z 412.3 [M+H] ⁺ .

Step 8: To 4-[[4-(4-aminophenyl)piperidin To a solution of N-[4-[4-[[4-hydroxy-1-(4-nitrophenyl)-4-piperidinyl]methyl]piperidin-4-ol (1.50 g, 1.30 mmol, 35.57% purity) in DCM (15 mL) was added Boc ₂ O (311.27 mg, 1.43 mmol) and TEA (262.41 mg, 2.59 mmol). The mixture was stirred at 20° C. for 12 h. The mixture was concentrated at 40° C. under reduced pressure to give N-[4-[4-[[4-hydroxy-1-(4-nitrophenyl)-4-piperidinyl]methyl]piperidin-4-ol as a yellow oil. -1-yl]phenyl]carbamic acid tributyl ester (0.80 g, 96.13% yield). LCMS (ESI ⁺ ) m/z 512.4 [M+H] ⁺ .

Step 9: Under _N2 atmosphere, add N-[4-[4-[[4-hydroxy-1-(4-nitrophenyl)-4-piperidinyl]methyl]piperidinyl To a solution of tributyl [4-[4-[[1-(4-aminophenyl)-4-hydroxy-4-piperidinyl]methyl]piperidinyl]carbamate (0.80 g, 1.25 mmol) in THF (10 mL) was added Pd/C (10%, 182.38 mg). The mixture was degassed and purged with _H2 (3x). The mixture was stirred under _H2 (15 psi) at 20 °C for 2 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered through celite. The filtrate was concentrated under reduced pressure to give N-[4-[4-[[1-(4-aminophenyl)-4-hydroxy-4-piperidinyl]methyl]piperidinyl]carbamate as a yellow oil. -1-yl]phenyl]carbamic acid tributyl ester (0.60 g, 88.62% yield). The product was used in the next step without further purification. LCMS (ESI ⁺ ) m/z 482.4 [M+H] ⁺ .

Step 10: Reverse the reaction mixture of N-[4-[4-[[1-(4-aminophenyl)-4-hydroxy-4-piperidinyl]methyl]piperidinyl -1-yl]phenyl]carbamic acid tributyl ester (0.60 g, 1.10 mmol) was added to di To a solution of 2-(4-bromopiperidine-2,6-dione) (212.10 mg, 1.10 mmol) in oxane (8 mL) was added DIEA (428.30 mg, 3.31 mmol) and NaI (16.56 mg, 110.46 µmol). The mixture was stirred at 100 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was poured into water (10 mL) and extracted with EA (3 × 10 mL). The combined organic layers were washed with brine (10 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure to give the crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 1:1) to give N-[4-[4-[[1-[4-[(2,6-dihydroxy-3-piperidinyl)amino]phenyl]-4-hydroxy-4-piperidinyl]methyl]piperidinyl as a white solid. -1-yl]phenyl]carbamic acid tributyl ester (0.60 g, 86.75% yield). LCMS (ESI ⁺ ) m/z 593.4 [M+H] ⁺ .

Step 11: N-[4-[4-[[1-[4-[(2,6-dioxo-3-piperidinyl)amino]phenyl]-4-hydroxy-4-piperidinyl]methyl]piperidinyl A solution of tributyl 3-[4-[4-[[4-(4-aminophenyl)piperidinamide (0.3 g, 479.11 µmol, 94.66% purity) in TFA (0.3 mL) and DCM (3 mL) was stirred at 20 °C for 12 h. The mixture was concentrated under reduced pressure at 40 °C to give 3-[4-[4-[[4-(4-aminophenyl)piperidinamide as a yellow oil. [-1-yl]methyl]-4-hydroxy-1-piperidinyl]anilino]piperidine-2,6-dione (0.15 g, 33.17% yield). LCMS (ESI ⁺ ) m/z 493.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H), 9.01 (br s, 1H), 7.27 (br d, J = 8.2 Hz, 2H), 6.85 - 6.72 (m, 4H), 6.59 (br d, J = 8.7 Hz, 2H), 5.33 (d, J = 7.2 Hz, 1H), 4.23 - 4.13 (m, 1H), 4.07 (s, 1H), 3.09 - 2.98 (m, 6H), 2.95 - 2.83 (m, 2H), 2.76 - 2.64 (m, 5H), 2.60 - 2.53 (m, 2H), 2.32 (s, 2H), 2.10 (dt, J = 8.7, 4.2 Hz, 1H), 1.91 - 1.75 (m, 1H), 1.73 - 1.61 (m, 2H), 1.56 (br d, J = 12.3 Hz, 2H). Intermediate 43 2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl methanesulfonate (Figure 40)

Step 1: To a mixture of 2-(4-aminophenyl) (120.0 mg, 874.77 µmol), and (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-(methylsulfonyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one (436.1 mg, 1.05 mmol) in DMF (3 mL) at 20 °C under _N2 was added DIEA (226.1 mg, 1.75 mmol) in one portion. The mixture was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40°C under reduced pressure to give a crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:1 to 0:1) to give 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-[b]pyridin-2-yl]-6-[4-(2-hydroxyethyl)anilino]pyrazolo[3,4-d]pyrimidin-3-one (330.0 mg, 75.93%). LCMS (ESI ⁺ ) m/z 473.2 [M+H] ⁺ .

Step 2: To a solution of the product obtained from step 1 above (330.0 mg, 664.21 µmol) in DCM (6 mL) at 25 °C under _N2 were added TEA (134.4 mg, 1.33 mmol) and MsCl (83.7 mg, 730.63 µmol) in one batch. The mixture was stirred at 25 °C for 1 h. TLC showed that the starting material was consumed and a new spot was detected. The reaction mixture was purified by preparative TLC (PE:EA = 1:1, Rf = 0.5) to give 2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl methanesulfonate ( Intermediate 43 ) (160.0 mg, 43%). Intermediate 44 3-[4-(1,4-diazo -1-yl)anilino]piperidin-2,6-dione (Figure 41)

Step 1: Add 4-(4-aminophenyl)-1,4-diazolyl To a solution of tributyl-1-carboxylate (1.5 g, 5.04 mmol) and 3-bromopiperidine-2,6-dione (1.0 g, 5.54 mmol) in DMF (40 mL) was added NaHCO ₃ (846.9 mg, 10.08 mmol). The mixture was stirred at 60 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated in vacuo to give 4-[4-[(2,6-dioxo-3-piperidinyl)amino]phenyl]-1,4-diazo -1-carboxylic acid tributyl ester (1.0 g, 42%), which was used in the next step without further purification. LC/MS (ESI) m/z 403.3 [M+H] ⁺ .

Step 2: To a solution of the product obtained from step 1 (0.60 g, 1.29 mmol) in DCM (20 mL) and TFA (2 mL) was stirred at 25 °C for 2 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by preparative HPLC to give 3-[4-(1,4-diazo)- -1-yl)anilino]piperidine-2,6-dione (150.0 mg, 36%). LC/MS (ESI) m/z 303.3 [M+H] ⁺ . Intermediate 47 and Intermediate 48 (R)-2-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)-2-hydroxyethyl methanesulfonate and (S)-2-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)-2-hydroxyethyl methanesulfonate (Figure 42)

Step 1: 2-Allyl-6-[4-(1,2-dihydroxyethyl)anilino]-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one (31.35% yield) was synthesized from 1-(4-aminophenyl)ethane-1,2-diol and (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-(methylsulfonyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one using 2-propanol as solvent. LC/MS (ESI) m/z 489.3 [M+H] ⁺ .

Step-2: [2-[4-[[2-Allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-2-hydroxy-ethyl]methanesulfonate (26% yield) was synthesized from the product obtained in step 1 above by following a similar procedure as described in step 2 of the synthesis of intermediate 43 . The obtained product was further subjected to SFC purification to provide [(2R)-2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-2-hydroxy-ethyl]methanesulfonate ( intermediate 47 ) (39% yield) and [(2S)-2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-2 -hydroxy-ethyl] methanesulfonate ( Intermediate 48 ) (42% yield). Intermediate 50 3-[4-[4-[[1-(4-aminophenyl)-4-piperidinyl]amino]-1-piperidinyl]anilino]piperidine-2,6-dione (Figure 43)

Step 1: N-[4-[4-[[1-[4-[(2,6-dioxo-3-piperidinyl)amino]phenyl]-4-piperidinyl]amino]-1-piperidinyl]phenyl]carbamic acid tert-butyl ester (0.3 g, 27.85%) was synthesized from 3-((4-(4-aminopiperidin-1-yl)phenyl)amino)piperidine-2,6-dione and N-[4-(4-oxo-1-piperidinyl)phenyl]carbamic acid tert-butyl ester. LC/MS (LCMS) m/z 577.4 [M+H] ⁺ .

Step 2: 3-[4-[4-[[1-(4-aminophenyl)-4-piperidinyl]amino]-1-piperidinyl]anilino]piperidine-2,6-dione (53.26% yield) was synthesized from the product obtained in step 1 above by following a similar procedure as described in step 2 of the synthesis of intermediate 44. LC/MS (ESI) m/z 477.3 [M+H] ⁺ . Intermediate 51 (2-(3-(2,6-dioxopiperidin-3-yl)benzyl)-2-azaspiro[3.3]hept-6-yl)methyl methanesulfonate (Figure 44)

Step 1: 2,6-dibenzyloxy-3-(4,4,5,5-tetramethyl-1,3,2-dihydro- _1- boron -2-yl)pyridine (7.29 g, 8.73 mmol), and 2-(3-bromophenyl)-1,3-dibromophenyl (2.00 g, 8.73 mmol) in di To a mixture of 2-(4-(2-( _4- (2-(2-( _2- ( _2- (2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2- ₍ 2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-(2-( _2- (2-(2-(2-(2-(2-(2-( _2- The crude product was purified by silica gel chromatography (eluted with PE:EA = 100:1 to 0:1, Rf = 0.4) to give 2,6-dibenzyloxy-3-[3-(1,3- -2-yl)phenyl]pyridine (2.00 g 50.43%). LC/MS (ESI) m/z 440.3 [M+H] ⁺ .

Step 2: 2,6-dibenzyloxy-3-[3-(1,3- To a solution of 1,2-dimethoxy-2-yl)phenyl]pyridine (2.00 g, 4.40 mmol, 96.72% pure) in THF (40 mL) was added Pd/C (0.47 g, 0.44 mmol, 10% pure) and TEA (445.5 mg, 4.40 mmol) dropwise under _N2 atmosphere. The reaction was stirred at 25 °C under _H2 (15 psi) for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter cake was washed with THF (50 mL) and the collected filtrate was concentrated to give 3-[3-(1,3-dimethoxy-2-yl)phenyl]pyridine (2.00 g, 4.40 mmol, 96.72% pure) in THF (40 mL) ... and the collected filtrate was concentrated to give 3-[3-(1,3-dimethoxy-2-yl)phenyl]pyridine (2.00 g, 4.40 mmol, 96.72% pure) in THF (40 mL) and the collected filtrate was concentrated to give 3-[3-(1,3-dimethoxy-2-yl)phenyl]pyridine -2-yl)phenyl]piperidin-2,6-dione (1.29 g, 55.20%). LC/MS (ESI) m/z 262.23 [M+H] ⁺ .

Step 3: Towards 3-[3-(1,3- To a solution of [0367] (2,6-dioxo-3-piperidinyl)phenyl]piperidin-2,6-dione (1.29 g, 4.94 mmol) in THF (20 mL) was added aqueous HCl (39.52 mmol 10.05 mL, 2 M) in batches at 25 °C under _N2 . The mixture was stirred at 55 °C for 3 h. TLC showed that the reaction was complete and a new spot was detected. The mixture was concentrated under reduced pressure to give a crude product. The crude product was purified by column chromatography on silica gel (eluted with PE:EA = 100:1 to 0:1, Rf = 0.4) to provide 3-(2,6-dioxo-3-piperidinyl)benzaldehyde (521 mg, 86.86%). ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.86 (s, 1H), 7.40 - 7.22 (m, 5H), 5.71 (s, 1H), 4.09 - 4.01 (m, 2H), 4.00 - 3.93 (m, 2H), 2.73 - 2.63 (m, 1H), 2.51 - 2.46 (m, 1H), 2.21 (dq, J = 12.3, 4.5, Hz 1H), 2.10 - 1.98 (m, 1H).

Step 4: 3-[3-[[6-(Hydroxymethyl)-2-azaspiro[3.3]hept-2-yl]methyl]phenyl]piperidine-2,6-dione (19.53% yield) was synthesized from the product obtained in step 3 above and 2-azaspiro[3.3]hept-6-ylmethanol. LC/MS (ESI) m/z 329.2 [M+H] ⁺ .

Step 5: [2-[[3-(2,6-dioxo-3-piperidinyl)phenyl]methyl]-2-azaspiro[3.3]hept-6-yl]methyl methanesulfonate ( Intermediate 51 ) as a white solid (47.19% yield) was synthesized from the product obtained in Step-4 above by following a similar procedure as described in Step-2 of the synthesis of Intermediate 43. LC/MS (ESI) m/z 407.2 [M+H] ⁺ . Intermediate 52 3-(4-(2-(4-(4-aminophenyl)piperidinyl)phenyl]methyl]-2-azaspiro[3.3]hept-6-yl]methyl methanesulfonate -1-yl)ethyl)phenyl)piperidin-2,6-dione (Figure 45)

Step 1: To a solution of 2-[4-(2,6-dibenzyloxy-3-pyridinyl)phenyl]ethanol (WO2023/098656 A1) (0.7 g, 1.07 mmol) in DCM (40.0 mL) at 0°C was added DMP (1.44 g, 3.4 mmol, 1.05 mL). The reaction was stirred at 25°C for 2 h. TLC (PE: EA = 1:1, Rf = 0.5) showed that the starting material was consumed and a new spot was detected. The reaction was quenched with H ₂ O (50.0 mL) at 25°C and extracted with DCM (3 × 50.0 mL). The organic layer was dried over Na ₂ SO ₄ . After filtration, the filtrate was concentrated under reduced pressure to give a crude product, which was purified by column chromatography on silica gel (eluted with PE:EA = 100:1 to 1:1) to give 2-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]acetaldehyde (0.6 g, 86.14%). LC/MS (ESI) m/z 410.2 [M+H] ⁺ .

Step 2: 1-[2-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]ethyl]-4-(4-nitrophenyl)piperidin (45.44% yield) was synthesized from the product obtained from step 1 above and 1-(4-nitrophenyl)piperidin .

Step 3: 3-[4-[2-[4-(4-aminophenyl)piperidin 1-((1-(4-(2,6-dioxopiperidin-3-yl)phenyl)piperidin-4-yl)methyl)azine-3-yl methanesulfonate ( Figure 46 )

Step 1: 1-[4-(2,6-Dibenzyloxy-3-pyridinyl)phenyl]piperidine-4-carbaldehyde (31.38% yield) was synthesized by following a similar procedure as described in Step 1 of the synthesis of Intermediate 52. LC/MS (ESI) m/z 479.23 [M+H] ⁺ .

Step 2: 1-[[1-[4-(2,6-dibenzyloxy-3-pyridinyl)phenyl]-4-piperidinyl]methyl]azepan-3-ol (53% yield) was synthesized from the product obtained in step 1 above. LC/MS (ESI) m/z 536.3 [M+H] ⁺ .

Step 3: 3-[4-[4-(Hydroxymethyl)-1-piperidinyl]phenyl]piperidine-2,6-dione (95% yield) was synthesized from the product obtained in step 2 above. LC/MS (ESI) m/z 358.2 [M+H] ⁺ .

Step 4: [1-[[1-[4-(2,6-dioxo-3-piperidinyl)phenyl]-4-piperidinyl]methyl]azetidine-3-yl] methanesulfonate (41% yield) was synthesized from the product obtained in step 3 above. LC/MS (ESI) m/z 436.2 [M+H] ⁺ . Intermediate 54 4-(2,6-dioxo-3-piperidinyl)benzaldehyde (Figure 47)

Step 1: To a solution of methyl 2-[4-[[tributyl(dimethyl)silyl]oxymethyl]phenyl]acetate (2.1 g, 7.13 mmol) in DMF (80 mL) at 0°C, propenamide (1.01 g, 14.26 mmol) and tBuOK (1.60 g, 14.26 mmol) were added. The reaction was stirred at 0°C for 1 h. TLC (PE:EA = 1:1, Rf=0.6) showed that the reaction was complete and the desired product was detected. The reaction was quenched with saturated NH ₄ Cl solution and extracted with EA (50 mL). The organic layer was washed with brine (30 mL), dried over Na ₂ SO ₄ and filtered. The filtrate was concentrated to give a crude product which was purified by flash column on silica gel to give 3-[4-[[tributyl(dimethyl)silyl]oxymethyl]phenyl]piperidine-2,6-dione (1.6 g, 67%). ¹ H NMR (400 MHz, CDCl ₃ ) δ 7.93 (br s, 1H), 7.23 (d, J = 8.1 Hz, 2H), 7.07 (d, J = 8.1 Hz, 2H), 4.63 (s, 2H), 3.69 (dd, J = 5.3, 9.2 Hz, 1H), 2.68 - 2.46 (m, 2H), 2.24 - 2.10 (m, 2H), 0.84 (s, 9H), 0.00 (s, 6H).

Step 2: To a solution of 3-[4-[[tributyl(dimethyl)silyl]oxymethyl]phenyl]piperidine-2,6-dione (1.6 g, 4.80 mmol) in THF (20 mL) at 25 °C was added aqueous HCl (2 N, 2 mL). The reaction was stirred at 25 °C for 1 h. TLC (PE:EA = 1:1, Rf=0.2) showed the reaction was complete. The reaction was concentrated under reduced pressure to give 3-(4-(hydroxymethyl)phenyl)piperidine-2,6-dione (0.8 g, 76%) which was used in the next step without further purification.

Step 3: To a solution of 3-[4-(hydroxymethyl)phenyl]piperidine-2,6-dione (0.42 g, 1.92 mmol) in DCM (30 mL) at 0 °C was added DMP (1.22 g, 2.87 mmol). The reaction was stirred at 0 °C for 1 h. TLC showed the reaction was complete. The reaction was quenched with saturated NaHCO ₃ solution and extracted with DCM (3 × 15 mL). The organic layer was dried over Na ₂ SO ₄ and filtered. The filtrate was concentrated to give a crude product, which was purified by column chromatography on silica gel (eluted with PE:EA = 50:1 to 5:1) to give 4-(2,6-dioxo-3-piperidinyl)benzaldehyde ( Intermediate 54 ) (0.3 g, 72%). Intermediate 55 (2-(4-(2,6-dioxo-3-piperidinyl)benzyl)-2-azaspiro[3.3]hept-6-yl)methyl methanesulfonate (Figure 48)

Step 1: To a solution of 2-azaspiro[3.3]hept-6-ylmethanol (0.3 g, 1.89 mmol) in THF (10 mL) was added 4-(2,6-dioxo-3-piperidinyl)benzaldehyde ( intermediate 54 , 409.9 mg, 1.89 mmol) and NaBH(OAc) ₃ (799.8 mg, 3.77 mmol) and TBSCl (284.4 mg, 1.89 mmol, 231.2 µL) at 25 °C. The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired compound was detected. The mixture was diluted with water (10 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine (3 × 10 mL) and dried over Na ₂ SO _4. After filtration, the filtrate was concentrated under reduced pressure to give 3-[4-[[6-(hydroxymethyl)-2-azaspiro[3.3]hept-2-yl]methyl]phenyl]piperidine-2,6-dione (0.1 g, 12.5%). LC/MS (ESI) m/z 329.2 [M+H] ⁺ .

Step 2: [2-[[4-(2,6-dioxo-3-piperidinyl)phenyl]methyl]-2-azaspiro[3.3]hept-6-yl]methyl methanesulfonate ( Intermediate 55 ) (61% yield) was synthesized from the product obtained in Step 2 above by following a similar procedure as described in Step 2 of the synthesis of Intermediate 43. LC/MS (ESI) m/z 407.2 [M+H] ⁺ . Intermediate 56 3-((4-(2,6-dioxo-3-piperidinyl)phenyl)amino)propyl methanesulfonate (Figure 49)

Step 1: To a mixture of 3-(4-aminophenyl)piperidine-2,6-dione (0.70 g, 2.00 mmol, 58.45% purity) and 3-bromopropan-1-ol (278.5 mg, 2.00 mmol) in DMF (14 mL) was added DIEA (517.8 mg, 4.01 mmol) in one portion at 25 °C under _N2 . The mixture was stirred at 80 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 60 °C under reduced pressure to give the crude product. The crude product was purified by preparative TLC (PE:EA = 0:1, Rf = 0.4) to give 3-[4-(3-hydroxypropylamino)phenyl]piperidine-2,6-dione (0.15 g, 15.49%).

Step 2: 3-[4-(2,6-dioxo-3-piperidinyl)anilino]propyl methanesulfonate (47% yield) was synthesized from the product obtained in step 1 above by following a similar procedure as described in step 2 of the synthesis of intermediate 43. LC/MS (ESI) m/z 436.2 [M+H] ⁺ . Intermediate 57 4-(2,6-dioxo-3-piperidinyl)phenylethyl methanesulfonate (Figure 50)

4-(2,6-Dihydroxypiperidin-3-yl)phenethyl methanesulfonate ( Intermediate 57 ) (57% yield) was synthesized from 3-[4-(2-hydroxyethyl)phenyl]piperidine-2,6-dione by following a similar procedure as described in step 2 of the synthesis of Intermediate 43. LC/MS (ESI) m/z 329.1 [M+H] ⁺ . Intermediate 58 2-((4-(2,6-Dihydroxypiperidin-3-yl)phenyl)amino)ethyl methanesulfonate (Figure 51)

2-[4-(2,6-dioxo-3-piperidinyl)anilino]ethyl methanesulfonate (22.27%) was synthesized from 3-[4-(2-hydroxyethylamino)phenyl]piperidine-2,6-dione. Intermediate 60 3-[4-(2,6-dioxo-3-piperidinyl)phenyl]propanal (Figure 52)

Step 1: 3-(4-bromophenyl)propan-1-ol (0.5 g, 2.32 mmol) was added to dichloromethane at 20 °C. 2,6 _- Bis(benzyloxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxane) was added to the mixture of 10:1 (11 mL). boron -2-yl)-pyridine (1.16 g, 2.79 mmol), Pd(dppf)Cl ₂ (85.05 mg, 116.23 µmol), and K ₂ CO ₃ (642.56 mg, 4.65 mmol). The mixture was stirred at 100 °C under N ₂ for 12 h. LCMS showed that the starting material was consumed and the desired product was detected. The mixture was poured into H ₂ O (10 mL). The mixture was extracted with EA (3 × 10 mL). The organic phase was washed with brine (5 mL), dried over anhydrous Na ₂ SO ₄ and concentrated in vacuo to give a residue. The crude product was purified by column chromatography on silica gel (with PE:EA = 100:1 to 10:1) to give 3-[4-(2,6-dibenzyloxy-3-pyridyl)phenyl]propan-1-ol (0.5 g, 37.13%) as a white solid. LC/MS (ESI) m/z 426.2 [M+H] ⁺ .

Step 2: 3-[4-(3-Hydroxypropyl)phenyl]piperidine-2,6-dione (38% yield) was synthesized from the product obtained in Step 1 above by following a similar procedure as described in Step 2 of the synthesis of Intermediate 46 .

Step 3: 3-[4-(2,6-dioxo-3-piperidinyl)phenyl]propanal ( Intermediate 60 ) (50% yield) was synthesized from the product obtained in Step 2 above by following a similar procedure as described in Step 1 of the synthesis of Intermediate 52. Example 1 : 3-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)benzyl)piperidinaldehyde -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 1 )

To a mixture of intermediate 1 (80.0 mg, 170 µmol, 84% purity) in i -PrOH (1 mL) at 20 °C was added a solution of 2-allyl-1-[( 7R )-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[ b ]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4- d ]pyrimidin-3-one (Huang et al., J. Med. Chem. (2021) 64:13004-13024, 70.8 mg, 170 µmol) in i -PrOH (0.5 mL). The mixture was then stirred at 80 °C under _N2 for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to provide compound 1 , 3-[4-[4-[[4-[[2-allyl-1-[(7 R )-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[ b ]pyridin-2-yl]-3-oxo-pyrazolo[3,4- d ]pyrimidin-6-yl]amino]phenyl]methyl]piperidin- -1-yl]anilino]piperidine-2,6-dione (10.3 mg, 8% yield, 97.17% purity). LC/MS (ESI) m/z 729.4 [M+H] ⁺ , RT: 2.696 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.74 (br s, 1H, NH), 10.25 (br s, 1H, NH), 8.88 (s, 1H), 7.92 (d, J = 8.1 Hz, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.70 (d, J = 8.4 Hz, 1H), 7.27 (d, J = 8.4 Hz, 2H), 6.74 (d, J = 8.9 Hz, 2H), 6.60 (d, J = 8.9 Hz, 2H), 5.68 (tdd, J = 16.8, 10.6, 5.8 Hz, 1H), 5.37 (d, J = 7.3 Hz, 1H), 5.05 (s, 1H, OH), 5.00 (dd, J = 10.3, 1.0 Hz, 1H), 4.86 (dd, J = 17.1, 1.0 Hz, 1H), 4.76 (br dd, J = 16.1, 4.9 Hz, 1H), 4.56 (br dd, J = 16.0, 6.1 Hz, 1H), 4.18 (ddd, J = 11.3, 6.9, 4.8 Hz, 1H), 3.47 (s, 2H), 3.04 - 2.87 (m, 5H), 2.85 - 2.65 (m, 2H), 2.62 - 2.53 (m, 1H), 2.49 - 2.54 δ 5.1 (m, 4H), 2.20 (ddd, J = 13.5, 8.3, 5.8 Hz, 1H), 2.10 (ddd, J = 13.3, 8.7, 4.4 Hz, 1H), 2.01 (ddd, J = 13.4, 8.4, 5.3 Hz, 1H), 1.94 - 1.77 (m, 2H), 1.76 - 1.64 (m, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 2 : 3-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenethyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 2 )

Compound 2 was prepared by following a similar procedure as described in Example 1 using intermediate 2 (0.120 g, 294 µmol) instead of intermediate 1 to provide the desired title product Example 2 after purification, 3-((4-(4-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenethyl)piperidin- -1-yl)phenyl)amino)piperidine-2,6-dione (13.8 mg, 18.6 µmol, 6.3% yield, 100% purity). ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH), 10.21 (br s, 1H, NH), 8.87 (s, 1H), 7.91 (d, J = 8.1 Hz, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.65 (br d, J = 8.4 Hz, 2H), 7.20 (d, J = 8.4 Hz, 2H), 6.76 (d, J = 8.9 Hz, 2H), 6.61 (d, J = 8.9 Hz, 2H), 5.74 - 5.61 (m, 1H), 5.37 (br d, J = 6.0 Hz, 1H, NH), 5.05 3.01 (m, 5H), 2.80 - 2.77 (m, 4H), 2.63 - 2.81 (m, 7H) , 2.26 - 2.14 (m, 1H), 2.16 - 2.22 (m, 1H) , 2.24 - 2.30 (m, 1H), 2.43 - 2.42 (m, 7H), 2.28 - 2.42 (m, 1H), 2.30 - 2.54 (m, 1H), 2.72 - 2.81 (m, 1H), 2.84 - 2.91 (m, 2H), 2.69 - 2.83 (m, 3H), 2.82 - 2.91 (m, 3H), 2.64 - 2.84 (m, 4H), 2.63 - 2.91 (m, 7H), 2.63 - 2.83 (m, 3H ), 13.4, 8.4, 5.3 Hz, 1H), 1.95 - 1.77 (m, 2H), 1.76 - 1.64 (m, 1H), 0.87 (t, J = 7.4 Hz, 2H). Example 3 : 3-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 3 )

Compound 3 was prepared by following a similar procedure as described in Example 1 using intermediate 3 (70.0 mg, 175 μmol, 94.91% purity) instead of intermediate 1. The mixture was filtered and the filtrate was concentrated to give a residue, which was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to give compound 3 , 3-((4-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)-4-nitro-2-nitro-3-ol -1-yl)phenyl)amino)piperidine-2,6-dione (12.0 mg, 9.4% yield, 98.42% purity). LC/MS (ESI ^- ) m/z 713.4 [MH] ^- , RT: 2.681 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.51 - 10.38 (m, 1H, NH), 9.74 (s, 1H, NH), 8.78 (s, 1H), 7.87 (d, J = 8.2 Hz, 1H), 7.69 (d, J = 8.2 Hz, 1H), 7.58 (d, J = 8.9 Hz, 2H), 6.96 (d, J = 8.9 Hz, 2H), 6.84 (d, J = 8.8 Hz, 2H), 6.69 (d, J = 8.8 Hz, 2H), 5.78 - 5.63 (m, 1H), 5.17 (d, J = 7.0 Hz, 1H), 5.03 (d, 3.06 - 3.14 (m, 2H), 3.23 - 3.26 ( m , 4H), 3.12 - 3.18 (m, 4H), 3.01 - 3.70 (m, 1H) , 3.57 - 3.63 (m, 1H), 3.14 - 3.27 (m, 2H), 3.30 - 3.19 (m, 4H), 3.23 - 3.30 (m, 4H), 3.16 - 3.08 (m, 4H), 3.16 - 3.19 (m, 4H), 3.23 - 3.26 (m, 1H), 3.31 - 3.30 (m, 2H), 2.12 - 2.02 (m, 1H), 1.98 - 1.82 (m, 2H), 1.81 - 1.69 (m, 1H), 0.90 (t, J = 7.5 Hz, 3H). Example 4 : 3-((4-(4-(3-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)propyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 4 )

Compound 4 was prepared by following a similar procedure as described in Example 1 using intermediate 4 (80.0 mg, 193 µmol) instead of intermediate 1. The mixture was filtered and the filtrate was concentrated to give a residue which was purified by preparative HPLC (FA conditions) to give compound 4 , 3-((4-(4-(3-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)propyl)piperidin-4-yl)-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)propyl)piperidin-4-yl)-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl) (4-(2-yl)phenyl)amino)piperidine-2,6-dione (18.4 mg, 24.1 µmol, 7.8% yield, 99% purity). LC/MS (ESI ⁺ ) m/z 757.4 [M+H] ^{+ .} RT: 2.155 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H, NH), 10.21 (br s, 1H, NH), 8.87 (s, 1H), 7.92 (d, J = 8.1 Hz, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.65 (br d, J = 8.1 Hz, 2H), 7.17 (d, J = 8.1 Hz, 2H), 6.75 (d, J = 8.8 Hz, 2H), 6.61 (d, J = 8.8 Hz, 2H), 5.73 - 5.61 (m, 1H), 5.37 (d, J = 7.2 Hz, 1H), 5.05 (br s, 1H), 5.00 (d, J = 9.7 Hz, 1H), 4.86 (br d, J = 17.4 Hz, 1H), 4.81 - 4.70 (m, 1H), 4.56 (br dd, J = 16.0, 6.0 Hz, 1H), 4.23 - 4.13 (m, 1H), 3.02 - 2.96 (m, 1H), 2.94 (br s, 4H), 2.83 - 2.65 (m, 2H), 2.60 - 2.71 (m, 3H), 2.49 - 2.53 (m, 4H), 2.31 (br t, J = 7.0 Hz, 2H), 2.24 (ddd, J = 13.4, 8.1, 5.6 Hz, 1H), 2.15 - 2.06 (m, 1H), 2.01 (ddd, J = 13.4, 8.4, 5.3 Hz, 1H), 1.95 - 1.80 (m, 2H), 1.80 - 1.65 (m, 3H), 0.87 (t, J = 7.4 Hz, 3H). Example 5 : 3-((3-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)phenyl)amino)piperidin-2,6-dione (Compound 5 )

Compound 5 was prepared by following a similar procedure as described in Example 1 using intermediate 6 (0.250 g, 333 μmol, 50.47% purity) instead of intermediate 1. The mixture was filtered and the filtrate was concentrated to give a residue which was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to give compound 5 , 3-((3-(4-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-5-yl)-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-5-yl)-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl) -1-yl)phenyl)amino)piperidine-2,6-dione (24.4 mg, 10% yield, 100% purity). LC/MS (ESI ⁺ ) m/z 715.3 [M+H] ⁺ , RT: 2.179 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (br s, 1H, NH), 10.32 - 10.03 (m, 1H, NH), 8.83 (s, 1H), 7.94 (br d, J = 5.6 Hz, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.67 - 7.54 (m, 2H), 6.99 (d, J = 8.1 Hz, 1H), 6.95 (dd, J = 8.0, 8.0 Hz, 1H), 6.34 (s, 1H), 6.26 (dd, J = 8.0, 1.6 Hz, 1H), 6.18 (dd, J = 8.0, 1.6 Hz, 7 - 11 (m, 1H), 5.73 - 5.61 (m, 2H), 5.05 (s, 1H), 5.00 (dd, J = 10.2, 1.2 Hz, 1H), 4.86 (dd, J = 17.1, 1.2 Hz, 1H), 4.82 - 4.70 (m, 1H), 4.62 - 4.51 (m, 1H), 4.38 - 4.29 (m, 1H), 3.23 (s, 8H), 3.03 - 2.93 (m, 1H), 2.83 - 2.70 (m, 2H), 2.59 (td, J = 17.6, 4.2 Hz, 1H), 2.27 - 2.16 (m, 1H), 2.14 (td, J = 17.8, 4.2 Hz, 1H). = 8.6, 4.1 Hz, 1H), 2.02 (ddd, J = 13.5, 8.5, 5.3 Hz, 1H), 1.95 - 1.80 (m, 2H), 1.71 (qd, J = 13.8, 7.1 Hz, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 6 : 3-((4-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)piperidin-1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 6 )

To a mixture of intermediate 7 (0.34 g, 648 µmol, 60.12% purity) in DCM (2 mL) at 25 °C was added intermediate 8 (332 mg, 648 µmol) and DIEA (168 mg, 13.0 µmol,). The mixture was stirred at 25 °C under _N2 for 0.5 h. AcOH (77.9 mg, 13.0 µmol) and NaBH(OAc) ₃ (275 mg, 1.30 mmol) were added to the mixture at 0 °C. The mixture was stirred at 25 °C under _N2 for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to give compound 6 , 3-((4-(4-((4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin- (43.2 mg, 8.2% yield, 100% purity). LC/MS (ESI ⁺ ) m/z 812.4 [M+H] ⁺ , RT: 1.936 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H, NH), 10.19 - 10.03 (m, 1H, NH), 8.82 (s, 1H), 7.93 (br d, J = 7.6 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.58 (br s, 2H), 6.92 (br d, J = 8.9 Hz, 2H), 6.76 (d, J = 8.9 Hz, 2H), 6.60 (d, J = 8.8 Hz, 2H), 5.73 - 5.60 (m, 1H), 5.35 (d, J = 7.3 Hz, 1H, NH), 5.05 3H), 3.24 - 3.32 ( m , 3H), 3.26 ( s, 4H), 3.13 (br s, 4H), 3.02 - 2.96 (m, 1H), 2.82 - 2.68 (m, 2H), 2.62 - 2.53 (m, 2H), 2.48 - 2.46 (m, 2H), 2.26 - 2.30 (m, 3H), 2.44 - 2.54 (m, 2H), 2.30 - 2.58 (m, 3H), 2.71 - 2.83 (m, 3H), 2.84 - 2.90 (m, 1H), 2. δ 5.1 (m, 3H), 2.14 (dt, J = 8.9, 4.9 Hz, 1H), 2.06 (ddd, J = 13.4, 8.5, 5.3 Hz, 1H), 1.88 (br dd, J = 12.7, 5.5 Hz, 1H), 1.86 - 1.75 (m, 3H), 1.70 (br dd, J = 13.6, 7.3 Hz, 1H), 1.61 (br d, J = 3.9 Hz, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 7 : 3-(4-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (Compound 7 )

Compound 7 was prepared by following a similar procedure as described in Example 1 , using intermediate 10 (0.150 g, 0.325 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by preparative HPLC (column/size: X-SELECT C18 (19*250*5um) mobile phase A: 0.1% formic acid in water; mobile phase B: acetonitrile; gradient (time/%B): 0.01/10, 1/10, 10/30, 15/30, 15.01/100, 18/100, 18.01/10, 20/10. Flow rate: 16 mL/min.; solubility: acetonitrile + THF + water) to obtain compound 7 , 3-(4-(4-((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (57 mg, 22%). LC/MS (ESI ⁺ ) m/z 797.59 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.93 (d, J = 7.2 Hz, 1H), 7.69 (d, J = 8.4 Hz, 1H), 7.57 (br s, 2H), 7.04 (d, J = 8.8 Hz, 2H), 6.93 (d, J = 8.4 Hz, 2H), 6.90 (d, J = 8.8 Hz, 2H), 5.72 - 5.60 (m, 1H), 5.05 (br s, 1H, OH), 5.01 (d, J = 9.6 Hz, 1H), 4.86 (d, J = 17.2 Hz, 1H), 4.81 - 4.70 (m, 1H), 4.62 - 4.50 (m, 1H), 3.75 - 3.57 (m, 5H), 3.03 - 2.85 (m, 3H), 2.85 - 2.57 (m, 7H), 2.50 - 2.45 (m, 1H), 2.25 - 1.83 (m, 8H), 1.77 - 1.65 (m, 1H), 1.48 - 1.33 (m, 4H), 0.87 (t, J = 7.2 Hz, 3H). A formate ion peak was observed in ¹ H NMR. Example 8 : 3-(4-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)piperidin- -1-yl)phenyl)piperidin-2,6-dione (Compound 8 )

Compound 8 was prepared by following a similar procedure as described in Example 1 using intermediate 12 (0.100 g, 0.217 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by preparative HPLC (column/size: X-SELECT C18 (19*250*5um) mobile phase A: 5 mM ammonium acetate in water. Mobile phase B: acetonitrile; gradient (time/%B): 0.01/25, 1/25, 15/60, 17.5/60, 17.6/100, 20/100, 20.1/25, 23/25. Flow rate: 18 mL/min.; solubility: THF + ACN + water) to obtain compound 8 , 3-(4-(4-((1-(4-((2-allyl-1-(( R 7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)piperidin- -1-yl)phenyl)piperidin-2,6-dione (9 mg, 5%). LC/MS (ESI ⁺ ) m/z 797.50 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.93 (d, J = 7.2 Hz, 1H), 7.70 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.06 (d, J = 8.8 Hz, 2H), 6.92 (d, J = 8.8 Hz, 2H), 6.89 (d, J = 8.4 Hz, 2H), 5.73 - 5.60 (m, 1H), 5.05 (s, 1H, OH), 5.01 (d, J = 9.2 Hz, 1H), 3.87 (d, J = 17.2 Hz, 1H), 4.80 - 4.70 (m, 1H), 4.60 - 4.50 (m, 1H), 3.758 - 3.69 (m, 1H), 3.64 (br d, J = 12.0 Hz, 2H), 3.17(br s, 4H), 3.01 - 2.92 (m, 1H), 2.85 - 2.72 (m, 1H), 2.69 - 2.55 (m, 7H), 2.50 - 2.45 (m, 1H), 2.25 - 2.04 (m, 4H), 2.04 - 1.95 (m, 2H), 1.94 - 1.83 (m, 1H), 1.83 (br d, J = 12.0 Hz, 2H), 1.76 - 1.64 (m, 2H), 1.32 - 1.17 (m, 2H), 0.87 (t, J = 7.2 Hz, 3H). Example 9 : 3-(4-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (Compound 9 )

Compound 9 was prepared by following a similar procedure as described in Example 1 using intermediate 14 (0.190 g, 0.399 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by preparative HPLC (column/size: X-SELECT C18 (19*250*5um); mobile phase A: 10 mM ammonium acetate in water; mobile phase B: acetonitrile; gradient (time/%B): 0.01/25, 2/25, 10/45, 15/45, 15.1/100, 20.5/100, 20.6/45, 22.5/45. Flow rate: 18 mL/min.; solubility: ACN + water + THF) to obtain compound 9 , 3-(4-(4-(((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione (35 mg, 11%). LC/MS (ESI ⁺ ) m/z 811.62 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.92 (d, J = 7.2 Hz, 1H), 7.70 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.03 (d, J = 8.4 Hz, 2H), 9.91 (d, J = 9.0 Hz, 1H), 6.88 (d, J = 9.0 Hz, 1H), 5.72 - 5.60 (m, 1H), 5.05 (s, 1H, OH), 5.04 (d, J = 9.2 Hz, 1H), 96 - 3.54 (m, 7H), 3.73 - 3.81 (m, 1H), 3.77 - 3.91 (m, 1H) , 3.65 - 3.76 (m, 4H), 3.14 - 3.89 (m, 1H), 3.73 - 3.91 (m, 7H), 3.89 - 3.13 (m, 1H), 3.70 - 3.80 (m, 1H), 3.85 - 3.81 (m, 7H), 3.70 - 3.81 (m, 1H), 3.65 - 3.55 (m, 4H), 3.04 - 2.96 (m, 1H), 2.84 - 2.54 (m, 7H), 2.54 - 2.63 (m, 1H), 2.24 - 2.19 (m, 1H), 2.30 - 2.41 (m, 1H), 1.42 (m, 1H), 1.40 - 1.18 (m, 4H), 0.87 (t, J = 7.2 Hz, 3H). Example 10 : 3-(4-(2-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)ethoxy)phenyl)piperidine-2,6-dione (Compound 10 )

Compound 10 was prepared by following a similar procedure as described in Example 1 using intermediate 16 (0.210 g, 0.481 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by RP-HPLC (column/size: X-SELECT C18 (19*250*5um); mobile phase A: 5 mM ammonium acetate in water; mobile phase B: acetonitrile; gradient (time/%B): 0.01/20, 1/20, 10/45, 14/45, 14.1/100, 17/100, 17.1/20, 20/20; flow rate: 17 mL/min.; solubility: ACN + THF + water) to obtain compound 10 , 3-(4-(2-(((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)ethoxy)phenyl)piperidine-2,6-dione (23 mg, 6%). LC/MS (ESI ⁺ ) m/z 772.58 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.93 (d, J = 7.2 Hz, 1H), 7.69 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.13 (d, J = 8.8 Hz, 2H), 6.93-6.89 (m, 4H), 5.72 - 5.60 (m, 1H), 5.01 (s, 1H, OH), 5.00 (d, J = 9.2 Hz, 1H), 4.87 (d, J = 17.2 Hz, 1H), 4.80 - 3H), 4.70 (m, 1H), 4.60 - 4.50 (m, 1H), 4.01 (t, J = 5.6 Hz, 2H), 3.78 (dd, J = 11.4, 5.0 Hz, 1H), 3.63 (br d, J = 12.0 Hz, 2H), 3.03 - 2.92 (m, 1H), 2.88 (br s, 2H), 2.85 - 2.70 (m, 1H), 2.70 - 2.52 (m, 3H), 2.48 - 2.42 (m, 1H), 2.25 - 2.10 (m, 2H), 2.07 - 1.95 (m, 2H), 1.94 - 1.75 (m, 5H), 1.75 - 1.65 (m, 1H), 1.60 - 1.47 (m, 1H), 1.30 - 1.18 (m, 2H), 0.87 (t, J = 7.2 Hz, 3H). Example 11 : 3-(4-((1-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)piperidin-4-yl)oxy)phenyl)piperidine-2,6-dione (Compound 11 )

Compound 11 was prepared by following a similar procedure as described in Example 1 using intermediate 17 (0.210 g, 0.481 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by RP-HPLC (column/size: X-SELECT C18 (19*250*5um); mobile phase A: 10 mM ammonium acetate in water; mobile phase B: 100% acetonitrile; gradient (time/%B): 0.01/20, 1/30, 15/60, 15.1/100, 17/100, 17.1/30, 20/30; flow rate: 17 mL/min.; solubility: water + ACN + THF) to obtain compound 11 , 3-(4-((1-((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)piperidin-4-yl)oxy)phenyl)piperidine-2,6-dione (16 mg, 6%). LC/MS (ESI ⁺ ) m/z 812.60 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.92 (d, J = 7.2 Hz, 1H), 7.69 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.11 (d, J = 8.8 Hz, 2H), 6.93 - 6.86 (m, 4H), 5.72 - 5.60 (m, 1H), 5.05 (s, 1H, OH), 5.00 (d, J = 9.2 Hz, 1H), 4.87 (d, J = 17.2 Hz, 1H), 4.83 - 3.77 (m, 1H), 3.63 (br d, J = 12.0 Hz, 2H), 3.08 - 2.91 (m, 1H), 2.83 - 2.73 (m, 1H), 2.73 - 2.56 (m, 5H), 2.48 - 2.42 (m, 1H), 2.25 - 2.10 (m, 5H), 2.08 - 1.85 (m, 4H), 1.82 - 1.75 (m, 5H), 1.76 - 1.66 (m, 1H), 1.68 - 1.56 (m, 2H), 1.30 - 1.14 (m, 2H), 0.87 (t, J = 7.2 Hz, 3H). Example 12 : 4-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)methyl)-[1,3'-bipiperidinyl]-2',6'-dione (Compound 12 )

Compound 12 was prepared by following the similar procedure described in Example 1 using intermediate 19 (0.120 g, 209 μmol, 67.05% purity) instead of intermediate 1. The mixture was stirred at 80 °C under _N2 for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue which was purified by RP-HPLC (FA conditions) to obtain compound 12 , 4-((4-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)-[1,3'-bipiperidinyl]-2',6'-dione (24.1 mg, 16% yield, 100.00% purity). LC/MS (ESI ⁺ ) m/z 721.4 [M+H] ⁺ , RT: 1.892 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.56 (s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.92 (br d, J = 7.5 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.57 (br d, J = 1.3 Hz, 2H), 6.91 (br d, J = 9.0 Hz, 2H), 5.66 (tdd, J = 17.0, 10.4, 6.0 Hz, 1H), 5.05 (s, 1H, OH), 4.99 (dd, J = 10.4, 1 .1 Hz, 1H), 4.85 (br dd, 3H ), 2.63 - 2.52 (m, 3H), 2.48 (br s, 4H), 2.46 - 2.35 (m, 1H), 2.25 - 2.13 (m, 1H), 2.17 (d, J = 7.2 Hz, 2H), 2.14 - 2.22 (m, 3H), 2.22 - 2.30 (m, 1H), 2.19 (d, J = 7.2 Hz, 2H), 2.23 - 2.32 (m, 3H), 2.30 (d, J = 7.2 Hz, 2H), 2.18 (d, J = 7.2 Hz, 2H), 2.20 (d, J = 7.2 Hz, 2H), 2.48 (d, J = 7.2 Hz, 2H), 2.43 (d, J = 7.2 Hz, 2H), 2. δ 0.14 (m, 1H), 0.22 (m, 4H), 0.11 (m, 2H) , 0.17 (m, 3H), 0.20 (m, 1H), 0.16 (m, 2H), 0.25 (m, 3H), 0.13 (m, 4H), 0.26 (m, 2H), 0.13 (m, 3H), 0.26 (m, 2H), 0.11 (m, 2H), 0.26 (m, 3H). Example 13 : 3-((3-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)piperidin-1-yl)phenyl)amino)piperidin-2,6-dione (Compound 13 )

Compound 13 was prepared by following a similar procedure as described in Example 6 , using intermediate 22 (150 mg, 228 μmol, 48.01% purity) instead of intermediate 7 to react with intermediate 8. The mixture was stirred at rt for 2 h. LCMS showed that the starting material was consumed and a major product with the desired MS was detected. The mixture was concentrated under reduced pressure to give a residue. The residue was purified by preparative HPLC (FA conditions) to give compound 13 , 3-((3-(4-((4-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin- (4-(4-(4-piperidin-1-yl)methyl)piperidin-1-yl)phenyl)amino)piperidine-2,6-dione (11.5 mg, 6% yield, 100% purity) was obtained. LC/MS (ESI ⁺ ) m/z 812.4 [M+H] ⁺ , RT: 1.982 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H, NH), 10.12 (br s, 1H, NH), 8.82 (s, 1H), 7.93 (br d, J = 7.4 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.58 (br s, 2H), 6.92 (br d, J = 8.8 Hz, 2H), 6.90 (t, J = 8.1 Hz, 1H), 6.27 (s, 1H), 6.19 (dd, J = 8.1, 1.2 Hz, 1H), 6.11 (dd, J = 8.1, 1.2 Hz, 1H), 5.72 - 5.61 (m, 1H), 5.59 (d, J = 7.5 Hz, 1H, NH), 5.05 (s, 1H, OH), 4.99 (dd, J = 10.4, 0.8 Hz, 1H), 4.85 (br d, J = 17.6 Hz, 1H), 4.81 - 4.68 (m, 1H), 4.62 - 4.52 (m, 1H), 4.34 - 4.26 (m, 1H), 3.60 (br d, J = 11.4 Hz, 2H), 3.10 (br s, 4H), 3.02 - 2.93 (m, 1H), 2.82 - 2.69 (m, 2H), 2.65 - 2.55 (m, 3H), 2.50 (br s, 4H), 2.25 - 2.16 (m, 3H), 2.14 - 2.07 (m, 1H), 2.06 - 1.97 (m, 1H), 1.95 - 1.82 (m, 2H), 1.78 (br d, J = 12.5 Hz, 2H), 1.74 - 1.63 (m, 2H), 1.27 - 1.14 (m, 2H), 0.87 (t, J = 7.4 Hz, 3H). Example 14 : 3-(4-(6-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)-2,6-diazaspiro[3.3]hept-2-yl)phenyl)piperidine-2,6-dione (Compound 14 )

Compound 14 was prepared by following a similar procedure as described in Example 1 using intermediate 24 (100 mg, 126 μmol, 59.48% purity) instead of intermediate 1 to provide the desired title product, compound 14 , 3-(4-(6-((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)-2,6-diazaspiro[3.3]hept-2-yl)phenyl)piperidine-2,6-dione (23 mg, 22% yield, 97.53% purity). LCMS (ESI ⁺ ) m/z 809.3 [M+H] ⁺ , RT: 1.982 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.74 (s, 1H, NH), 10.10 (br s, 1H, NH), 8.81 (s, 1H), 7.92 (br d, J = 7.5 Hz, 1H), 7.69 (br d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 7.00 (br d, J = 8.1 Hz, 2H), 6.90 (br d, J = 8.6 Hz, 2H), 6.38 (br d, J = 8.3 Hz, 2H), 5.71 - 5.61 (m, 1H), 5.05 (s, 1H, OH), 5.03 (d, J = 10.4 Hz, 1H), 4.85 (d, J = 17.2 Hz, 1H), 4.81 - 4.70 (m, 1H), 4.63 - 4.50 (m, 1H), 3.84 (br s, 4H), 3.69 (br dd, J = 10.6, 4.8 Hz, 1H), 3.60 (br d, J = 10.9 Hz, 1H), 3.27 (br s, 4H), 3.01 - 2.92 (m, 1H), 2.84 - 2.73 (m, 1H), 2.65 - 2.53 (m, 3H), 2.48 - 2.41 (m, 1H), 2.27 (br d, J = 6.3 Hz, 2H), 2.26 - 2.16 (m, 1H), 2.13 - 2.06 (m, 1H), 2.06 - 1.95 (m, 2H), 1.93 - 1.84 (m, 1H), 1.80 - 1.65 (m, 3H), 1.43 - 1.32 (m, 1H), 1.30 - 1.13 (m, 2H), 0.87 (br t, J = 7.3 Hz, 3H). Example 15 : 3-(4-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)butoxy)phenyl)piperidine-2,6-dione (Compound 16 )

Compound 15 was prepared by following a similar procedure as described in Example 1 using intermediate 26 (388 mg, 0.860 mmol) instead of intermediate 1. The mixture was stirred at rt for 48 h. The crude was diluted with saturated sodium bicarbonate solution (50 mL) and extracted with 10% MeOH in DCM (2 × 50 mL). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give the crude product. The crude product was purified by silica gel flash chromatography using 0 to 10% MeOH in DCM as eluent to give the enriched product (250 mg), which was further purified by RP-HPLC (column/size: XBRIDGE C8 (19*150*5um); mobile phase A: 10 mM ammonium acetate in water; mobile phase B: acetonitrile; gradient (time/%B): 0.1/10, 1/10, 10/40, 13/40, 13.1/100, 17/100, 17.1/10, 19/10; flow rate: 18 mL/min.; solubility: acetonitrile+THF+water) to obtain compound 15 , 3-(4-(4-((1-(4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro- 5H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro- 1H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)butyloxy)phenyl)piperidine-2,6-dione (111 mg, 18%). LCMS (ESI ⁺ ) m/z 786.64 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (br s, 1H, NH), 10.11 (br s, 1H, NH), 8.81 (s, 1H), 7.93 (d, J = 7.2 Hz, 1H), 7.69 (d, J = 8.0 Hz, 1H), 7.55 (br s, 2H), 7.11 (d, J = 8.4 Hz, 2H), 6.91 (d, J = 9.2 Hz, 2H), 6.88 (d, J = 8.4 Hz, 2H), 5.73 - 5.60 (m, 1H), 5.01 (br s, 1H, OH), 4.99 (d, J = 9.6 Hz, 1H), 3.77 (dd, J = 11.4, 5.0 Hz, 1H), 3.62 - 3.52 (m, 2H), 3.03 - 2.92 (m, 2H) , 2.83 - 2.72 (m, 1H), 2.72 - 2.63 (m, 3H), 2.61 (t, J = 6.8 Hz, 2H), 2.52 - 2.43 (m, 1H) , 2.25 - 2.09 (m, 2H), 2.10 - 2.16 (m, 3H), 2.12 - 2.28 (m, 1H), 2.14 - 2.30 (m, 2H), 2. (m, 2H), 1.95 - 1.83 (m, 3H), 1.80 - 1.65 (m, 3H), 1.61 - 1.50 (m, 2H), 1.40 - 1.30 (m, 2H), 0.87 (t, J = 7.4 Hz, 3H). Example 16 : 3-(4-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)piperidin-1-yl)phenyl)piperidin-2,6-dione (Compound 16 )

Compound 16 was prepared by following a similar procedure as described in Example 6 , using 1-(4-(2,6-dioxopiperidin-3-yl)phenyl)piperidine-4-carbaldehyde (reference: WO 2022/012622, P150, 58.6 mg, 0.195 mmol) instead of intermediate 7 to react with intermediate 8. The mixture was stirred at rt for 16 h. The reaction was quenched with water (35 mL) and extracted with dichloromethane (2 × 50 mL). The organic layer was washed with water (20 mL) and saturated sodium bicarbonate solution (20 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The crude product was purified by preparative HPLC (column/size: x-BRIDGE C8; mobile phase A: 5 mM ammonium acetate; mobile phase B: acetonitrile; gradient (time/%B): 0.01/20, 1/20, 10/45, 15/45, 15.1/100, 19/100, 19.1/20, 22/20; solubility: acetonitrile + THF + water; flow rate: 18 mL/min) to afford compound 16 , 3-(4-(4-((4-((2-allyl-1-(( R )-7-ethyl-7-hydroxy-6,7-dihydro-5 H -cyclopenta[ b ]pyridin-2-yl)-3-oxo-2,3-dihydro-1 H -pyrazolo[3,4- d ]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)methyl)piperidin-1-yl)phenyl)piperidin-2,6-dione (33 mg, 21%). LCMS (ESI ⁺ ) m/z 797.73 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (br s, 1H, NH), 10.11 (br s, 1H, NH), 8.82 (s, 1H), 7.93 (d, J = 6.8 Hz, 1H), 7.70 (d, J = 8.0 Hz, 1H), 7.56 (br s, 2H), 7.03 (d, J = 8.4 Hz, 2H), 6.92 (d, J = 8.8 Hz, 2H), 6.89 (d, J = 8.8 Hz, 2H), 5.75 - 5.60 (m, 1H), 5.01 (br s, 1H, OH), 5.03 (d, J = 10.4 Hz, 3H), 4.86 (d, J = 17.2 Hz, 1H), 4.82 - 4.70 (m, 1H), 4.62 - 4.50 (m, 1H), 3.72 (dd, J = 11.0, 5.0 Hz, 1H), 3.67 (br d, J = 12.4 Hz, 2H), 3.11 (br s, 4H), 3.05 - 2.93 (m, 1H), 2.85 - 2.73 (m, 1H), 2.72 - 2.57 (m, 4H), 2.53 - 2.43 (m, 3H), 2.38 - 2.07 (m, 3H), 2.06 - 1.95 (m, 3H), 1.93 - 1.83 (m, 1H), 1.81 (br d, J = 11.6 Hz, 2H), 1.78 - 1.65 (m, 3H), 1.30 - 1.15 (m, 2H), 0.87 (t, J = 7.2 Hz, 3H). Example 17 : 3-[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin- -1-yl]phenyl]piperidine-2,6-dione ( Compound 17 )

To a solution of 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3-one (186.6 mg, 449.24 µmol) in iPrOH (2 mL) at 25 °C was added 3-[4-[4-(4-aminophenyl)piperidin- -1-yl]phenyl]piperidine-2,6-dione (intermediate 27 ) (100.0 mg, 224.62 µmol). The reaction was stirred at 80 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative _HPLC ( _NH4HCO3 conditions) to provide 3-[4-[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidine-2,6-dione as a yellow solid. -1-yl]phenyl]piperidine-2,6-dione ( Compound 17 ) (30.0 mg, 19.09% yield, 100.00% purity). LCMS (ESI) m/z 700.3 [M+H], RT: 2.266 min. ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.78 (s, 1H), 10.25 - 10.05 (m, 1H), 8.83 (s, 1H), 8.03 - 7.85 (m, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.66 - 7.49 (m, 2H), 7.09 (d, J = 8.6 Hz, 2H), 6.99 (br t, J = 9.3 Hz, 4H), 5.67 (tdd, J = 16.9, 10.6, 5.9 Hz, 1H), 5.09 - 4.95 (m, 2H), 4.85 (br d, J = 17.1 Hz, 1H), 3.81 - 4.69 (m, 1H), 4.57 (br dd, J = 15.4, 4.9 Hz, 1H), 3.75 (dd, J = 11.1, 4.9 Hz, 1H), 3.29 - 3.23 (m, 8H), 3.04 - 2.91 (m, 1H), 2.83 - 2.72 (m, 1H), 2.68 - 2.60 (m, 1H), 2.47 - 2.41 (m, 1H), 2.27 - 2.09 (m, 2H), 2.08 - 1.96 (m, 2H), 1.89 (qd, J = 13.8, 7.0 Hz, 1H), 1.78 - 1.64 (m, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 18 : 3-[4-[4-[2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl]piperidin -1-yl]phenyl]piperidin-2,6-dione ( Compound 18 )

To a solution of 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3-one (200.5 mg, 482.51 µmol) in iPrOH (2 mL) at 20 °C was added 3-[4-[4-[2-(4-aminophenyl)ethyl]piperidin- -1-yl]phenyl]piperidine-2,6-dione ( intermediate 28 ) (0.1 g, 241.25 µmol). The reaction was stirred at 80 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative _HPLC ( _NH4HCO3 conditions) to provide 3-[4-[4-[2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl]piperidine as a yellow solid. -1-yl]phenyl]piperidine-2,6-dione ( Compound 18 ) (22.0 mg, 12.5% yield, 100% purity). LCMS (ESI ⁺ ) m/z 728.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.77 (s, 1H), 10.29 - 10.14 (m, 1H), 8.87 (s, 1H), 7.91 (d, J = 8.1 Hz, 1H), 7.74 - 7.58 (m, 3H), 7.21 (d, J = 8.5 Hz, 2H), 7.05 (d, J = 8.8 Hz, 2H), 6.90 (d, J = 8.8 Hz, 2H), 5.67 (tdd, J = 16.8, 10.6, 5.9 Hz, 1H), 5.05 (s, 1H), 5.00 (dd, J = 10.3, 1.3 Hz, 1H), 4.86 (dd, J = 17.0, 1.3 Hz, 1H), 4.75 (br dd, J = 15.6, 4.4 Hz, 1H), 4.56 (br dd, J = 16.1, 6.1 Hz, 1H), 3.73 (dd, J = 10.9, 4.9 Hz, 1H), 3.18 - 3.07 (m, 4H), 2.99 - 2.89 (m, 1H), 2.81 - 2.70 (m, 3H), 2.68 - 2.61 (m, 1H), 2.61 - 2.53 (m, 6H), 2.48 - 2.41 (m, 1H), 2.24 - 2.09 (m, 2H), 2.10 - 2.28 (m, 3H), 2. 1.95 (m, 2H), 1.94 - 1.83 (m, 1H), 1.76 - 1.64 (m, 1H), 0.86 (t, J = 7.4 Hz, 3H). Example 19 : 3-[[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin- -1-yl]cyclohexyl]amino]piperidine-2,6-dione ( Compound 19 )

To a solution of 2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3-one (151.3 mg, 364.20 µmol) in iPrOH (2 mL) at 25 °C was added 3-[[4-[4-(4-aminophenyl)piperidin- [0136]-1-yl]cyclohexyl]amino]piperidine-2,6-dione ( Intermediate 29 ) (100.0 mg, 182.10 µmol, 70.20% purity). The reaction was stirred at 80 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative HPLC (NH ₄ HCO ₃ conditions) to provide 3-[[4-[4-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin-2-yl] as a yellow solid. -1-yl]cyclohexyl]amino]piperidine-2,6-dione ( Compound 19 ) (15.0 mg, 11.43% yield, 100% purity). LCMS (ESI ⁺ ) m/z 721.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.70 (br s, 1H), 10.21 - 10.01 (m, 1H), 8.82 (s, 1H), 7.92 (br d, J = 7.4 Hz, 1H), 7.69 (d, J = 8.3 Hz, 1H), 7.57 (br s, 2H), 6.91 (br d, J = 8.9 Hz, 2H), 5.67 (tdd, J = 16.8, 10.5, 5.9 Hz, 1H), 5.04 (s, 1H), 4.99 (dd, J = 10.2, 0.9 Hz, 1H), 4.85 (br d, J = 17.9 Hz, 3H), 2.06 - 2.14 (m, 2H), 2.54 - 2.53 (m, 3H), 2.23 - 2.16 (m, 2H), 2.30 - 2.39 (m, 1H), 4.81 - 4.68 (m, 1H), 4.56 (br dd, J = 15.8, 5.8 Hz, 1H), 3.42 (dd, J = 10.4, 4.8 Hz, 1H), 3.09 (br s, 4H), 3.02 - 2.91 (m, 1H), 2.85 - 2.72 (m, 2H), 2.65 - 2.57 (m, 4H), 2.57 - 2.52 (m, 3H), 2.25 - 2.15 (m, 2H), 2.06 (ddd, J = 12.9, 7.6, 5.2 Hz, 2H), 1.94 - 1.86 (m, 1H), (m, 6H), 1.48 (br d, J = 7.4 Hz, 4H), 0.87 (t, J = 7.4 Hz, 3H). Example 20 : (R)-4-(4-(4-(((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 20 )

To a solution of 4-(4-(4-oxopiperidin-1-yl)phenyl)piperidine-2,6-dione ( Intermediate 30 ) (0.05 g, 174.63 µmol) and (R)-2-allyl-6-((4-(4-(aminomethyl)piperidin-1-yl)phenyl)amino)-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one ( Intermediate 31 ) (94.41 mg, 174.63 µmol) in DCM (1 mL) was added AcOH (1.05 mg, 17.46 µmol, 1 µL) to adjust pH = 5-6. Then, NaBH(OAc) ₃ (74.02 mg, 349.25 µmol) was added after 2 h at 25 °C. The reaction was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by preparative _HPLC ( _NH4HCO3 condition) to give the pure product (R)-4-(4-(4-(((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 20 ) (0.012 g, 14.48 μmol, 8.29% yield, 97.88% purity) which was obtained as a white solid. LCMS (ESI ⁺ ) m/z 833.5 [M+Na] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.79 (s, 1H), 10.17 - 10.03 (m, 1H), 8.81 (s, 1H), 7.97 - 7.86 (m, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br d, J = 3.5 Hz, 2H), 7.11 (d, J = 8.8 Hz, 2H), 6.97 - 6.83 (m, 4H), 5.67 (tdd, J = 16.8, 10.5, 6.0 Hz, 1H), 5.04 (s, 1H), 5.02 - 4.97 (m, 1H), 4.85 (br d, J = 17.4 Hz, 1H), 4.81 - 4.69 (m, 1H), 4.61 - 4.51 (m, 1H), 3.71 - 3.52 (m, 4H), 3.01 - 2.93 (m, 1H), 2.79 - 2.65 (m, 5H), 2.64 - 2.55 (m, 4H), 2.47 - 2.46 (m, 1H), 2.25 - 2.11 (m, 2H), 2.06 - 1.97 (m, 1H), 1.93 - 1.78 (m, 5H), 1.70 (br dd, J = 13.6, 7.4, Hz, 1H), 1.57 - 1.41 (m, 2H), 1.38 - 1.19 (m, 5H), 0.87 (t, J = 7.4 Hz, 3H). Example 21 : 3-((3-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)amino)piperidine-2,6-dione ( Compound 21 )

To a solution of 3-((3-(4-aminopiperidin-1-yl)phenyl)amino)piperidine-2,6-dione ( Intermediate 33 ) (0.2 g, 290.77 µmol) in MeOH (0.5 mL) at 25 °C was added (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-((4-(4-oxopiperidin-1-yl)phenyl)amino)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one ( Intermediate 34 ) (50.9 mg, 96.92 µmol) and DIEA (125.2 mg, 969.23 µmol, 168.8 µL) AcOH (11.6 mg, 193.85 µmol, 11.10 µL) NaBH ₃ CN (9.1 mg, 145.38 µmol). The reaction was stirred at 25 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative HPLC ( _NH4HCO3 conditions) to provide 3-((3-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7 _- dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)amino)piperidine-2,6-dione ( Compound 21 ) (9.0 mg, 10.8% yield, 95.18% purity) as a yellow solid. LCMS (ESI ⁺ ) m/z 812.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H), 10.18 - 10.00 (m, 1H), 8.81 (s, 1H), 7.93 (br d, J = 7.5 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 6.97 - 6.90 (m, 2H), 6.90 - 6.85 (m, 1H), 6.27 (s, 1H), 6.19 (br d, J = 8.1 Hz, 1H), 6.11 (br d, J = 7.9 Hz, 1H), 5.73 - 5.62 (m, 1H), 5.62 - 5.54 (m, 1H), 5.05 (s, 1H), 5.00 (br d, J = 10.3 Hz, 1H), 4.85 (br d, J = 17.1 Hz, 1H), 4.81 - 4.67 (m, 1H), 4.64 - 4.49 (m, 1H), 4.37 - 4.23 (m, 1H), 3.68 - 3.48 (m, 4H), 3.01 - 2.91 (m, 1H), 2.85 - 2.62 (m, 8H), 2.56 (br s, 2H), 2.26 - 2.15 (m, 1H), 2.14 - 2.06 (m, 1H), 2.03 - 2.19 (m, 1H), 13.3, 8.4, 5.2 Hz, 1H), 1.96 - 1.76 (m, 6H), 1.70 (br dd, J = 13.6, 7.4 Hz, 1H), 1.40 - 1.22 (m, 4H), 0.87 (t, J = 7.4 Hz, 3H). Example 22 : 3-[4-[2-[[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopentyls[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]amino]ethylamino]phenyl]piperidine-2,6-dione ( Compound 22 )

To a mixture of 3-[4-(2-aminoethylamino)phenyl]piperidine-2,6-dione ( intermediate 35 ) (42.0 mg, 77.88 µmol, 67% purity, TFA salt) and 2-allyl-1-[(7R) _-7 -ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-[4-(4-oxo-1-piperidinyl)anilino]pyrazolo[3,4-d]pyrimidin-3-one ( intermediate 34 ) (40.0 mg, 76.10 µmol) in DCM (1.0 mL) at 20 °C under N2 was added NaBH(OAc) ₃ (32.3 mg, 152.21 µmol). The mixture was stirred at 20 °C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give a crude product. The crude product was purified by preparative HPLC ( _{NH4HCO3 conditions} ) to give 3-[4-[2-[[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]amino]ethylamino]phenyl]piperidine-2,6-dione ( Compound 22 ) (18.0 mg, 31.25% yield) as a white solid. LCMS (ESI ⁺ ) m/z 379.3 [M/2+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.73 (s, 1H), 10.22 - 9.94 (m, 1H), 8.81 (s, 1H), 7.99 - 7.86 (m, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.63 - 7.47 (m, 2H), 7.01 - 6.82 (m, 4H), 6.54 (d, J = 8.6 Hz, 2H), 5.72 - 5.61 (m, 1H), 5.51 - 5.46 (m, 1H), 5.07 - 4.96 (m, 2H), 4.90 - 4.70 (m, 2H), 4.62 - 4.51 3.67 - 3.56 (m, 4H), 3.09 (br d, J = 5.6 Hz, 2H), 3.01 - 2.93 (m, 1H), 2.77 (br t, J = 5.8 Hz, 3H), 2.73 - 2.65 (m, 4H), 2.44 - 2.39 (m, 1H), 2.24 - 2.16 (m, 1H), 2.11 - 2.04 (m, 1H), 2.06 (ddd, J = 13.1, 8.3, 4.3 Hz, 2H), 1.94 - 1.86 (m, 3H), 1.75 - 1.67 (m, 1H), 1.42 - 1.32 (m, 2H), 0.87 (t, J = 7.3 Hz, 3H). Example 23 : (R)-4-(3-(4-((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 23 )

To a solution of 4-(3-(4-oxopiperidin-1-yl)phenyl)piperidine-2,6-dione ( intermediate 37 ) (32.62 mg, 113.93 µmol) and (R)-2-allyl-6-((4-(4-aminopiperidin-1-yl)phenyl)amino)-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one ( intermediate 36 ) (0.05 g, 94.94 µmol) in DCM (1 mL) and MeOH (0.2 mL) was added AcOH (570.15 µg, 9.49 µmol) to adjust pH = 5-6. Then, NaBH(OAc) ₃ (40.24 mg, 189.89 µmol) was added after 2 h at 25 °C. The reaction was stirred at 20 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by preparative HPLC (NH _{3.H 2} O condition) to give the pure product. (R)-4-(3-(4-((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 23 ) was obtained as a white solid (0.019 g, 36.39 µmol, 38.33% yield, 99.72% purity). LCMS (ESI ⁺ ) m/z 797.5 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.82 (br s, 1H), 10.11 (br d, J = 1.6 Hz, 1H), 8.81 (s, 1H), 7.93 (br d, J = 6.8 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 7.14 (t, J = 7.9 Hz, 1H), 6.95 - 6.85 (m, 3H), 6.80 (br d, J = 8.3 Hz, 1H), 6.66 (d, J = 7.4 Hz, 1H), 5.73 - 5.61 (m, 1H), 5.08 (br s, d , J = 17.1 Hz, 1H), 4.76 (br d, J = 11.0 Hz, 1H), 4.61 - 4.52 (m, 1H), 3.69 - 3.55 (m, 4H), 3.02 - 2.91 (m, 1H), 2.86 - 2.57 (m, 12H), 2.24 - 2.15 (m, 1H), 2.08 - 1.97 (m, 1H), 1.95 - 1.82 (m, 5H), 1.70 (br dd, J =13.7, 7.6 Hz, 1H), 1.43 - 1.21 (m, 12H), 1. 5H), 0.87 (t, J = 7.4 Hz, 3H). Example 24 : (R)-3-(4-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 24A ） and (S)-3-(4-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 24B ） (Compound 24A) (Compound 24B)

3-[4-[4-[[1-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]-4-piperidinyl]methylamino]-1-piperidinyl]phenyl]piperidine-2,6-dione ( Compound 9 ) (100 mg) was purified by chiral SFC (column/size: CHIRALPAK-AS-H (30*250) mm, 5 µ; % CO ₂ : 50%; co-solvent %: 50% (0.2% 7N methanolic ammonia in ACN:MeOH) (1:1), total flow: 110 mL/min.; back pressure: 100 bar; UV: 307 nm; Solubility: MeOH; Number of injections: 3; Total purification time: 01:30 Hr; Run time per injection: 24:50 min; Instrument details: Brand/model: SFC-150-II. Nitrogen was purged into the collecting fractions to remove dissolved ammonia) to provide Peak 1 as a light yellow solid: 48.0 mg (( Compound 24A )) and Peak 2 as a light yellow solid: 45.0 mg ( Compound 24B ). Remarks: Stereochemistry was randomly assigned.

Peak 1: (R)-3-(4-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 24A ). LCMS (ESI ^- ) m/z 809.56 [MH] ^- . ¹ H NMR (400 MHz, DMSO- d ₆ ): δ 10.76 (s, 1H), 10.11 (br s, 1H), 8.81 (s, 1H), 7.93 (d, J = 7.2 Hz, 1H), 7.70 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.03 (d, J = 8.4 Hz, 2H), 6.93-6.87 (m, 4H), 5.72-5.60 (m, 1H), 5.05 (s, 1H), 5.00 (d, J = 9.2 Hz, 1H), 4.87 (d, J = 17.2 Hz, 1H), 4.83-4.87 (m, 4H). 7 (t, J = 7.2 Hz , 3H).

Peak 2: (S)-3-(4-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 24B ). LCMS (ESI ^- ) m/z 809.56 [MH] ^- . ¹ H NMR (400 MHz, DMSO- d ₆ ): δ 10.76 (s, 1H), 10.11 (br s, 1H), 8.81 (s, 1H), 7.93 (d, J = 7.6 Hz, 1H), 7.70 (d, J = 8.4 Hz, 1H), 7.56 (br s, 2H), 7.03 (d, J = 8.4 Hz, 2H), 6.93-6.87 (m, 4H), 5.72-5.60 (m, 1H), 5.05 (s, 1H), 5.00 (d, J = 9.2 Hz, 1H), 4.87 (d, J = 17.2 Hz, 1H), 4.81-4.70 (m, 7 (t, J = 7.2 Hz , 3H). Example 25 : (R)-4-(3-(4-(((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 25 )

To a solution of 4-(3-(4-oxopiperidin-1-yl)phenyl)piperidine-2,6-dione ( Intermediate 37 ) (0.05 g, 174.63 µmol) and (R)-2-allyl-6-((4-(4-(aminomethyl)piperidin-1-yl)phenyl)amino)-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one ( Intermediate 31 ) (47.21 mg, 87.31 µmol) in DCM (1 mL) was added AcOH (524.33 µg, 8.73 µmol) to adjust pH = 5-6. Then, NaBH(OAc) ₃ (37.01 mg, 174.63 µmol) was added after 2 h at 20°C. The reaction was stirred at 20°C for 12 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated at 40°C under reduced pressure to give the crude product. The crude product was purified by preparative HPLC (NH ₃ H ₂ O conditions) to give the pure product. (R)-4-(3-(4-(((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)methyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 25 ) was obtained as a white solid (0.01 g, 11.81 µmol, 13.53% yield, 94.14% purity). LCMS (ESI ⁺ ) m/z 811.5 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.81 (br s, 1H), 10.10 (br d, J = 4.1 Hz, 1H), 8.81 (s, 1H), 7.92 (br d, J = 7.1 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 7.14 (t, J = 7.9 Hz, 1H), 6.94 - 6.86 (m, 3H), 6.80 (dd, J =8.3, 1.8 Hz, 1H), 6.66 (d, J = 7.6 Hz, 1H), 5.72 - 5.61 (m, 1H), 5.08 (s, 3H), 4.96 (d, J = 9.4 Hz, 1H), 4.85 (br d, J = 17.0 Hz, 1H), 4.84 - 4.73 (m, 1H), 3.63 (br d, J = 12.1 Hz, 4H), 3.02 - 2.92 (m, 1H), 2.84 - 2.68 (m, 5H), 2.64 (br d, J = 4.3 Hz, 2H), 2.60 (br d, J = 4.1 Hz, 2H), 2.56 (br d, J = 9.9 Hz, 2H), 2.48 (br s, 1H), 2.24 (ddd, J = 13.6, 8.3, 5.8 Hz, 1H), 2.01 (ddd, J =13.4, 8.3, 5.3 Hz, 1H), 1.92 - 1.88 (m, 3H), 1.87 - 1.78 (m, 3H), 1.70 (br dd, J =13.6, 7.4 Hz, 1H), 1.52 - 1.44 (m, 1H), 1.38 - 1.21 (m, 4H), 0.87 (t, J = 7.4 Hz, 3H). Example 26 : (R)-4-(4-(4-((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 26 )

To a solution of 4-(4-(4-oxopiperidin-1-yl)phenyl)piperidine-2,6-dione ( intermediate 30 ) (0.05 g, 174.63 µmol) and (R)-2-allyl-6-((4-(4-aminopiperidin-1-yl)phenyl)amino)-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one ( intermediate 36 ) (72.85 mg, 145.52 µmol) in DCM (1 mL) and MeOH (0.2 mL) was added AcOH (873.89 µg, 14.55 µmol) to adjust pH = 5 to 6. Then, NaBH(OAc) ₃ (61.68 mg, 291.04 µmol) was added after 2 h at 25 °C, and the reaction was stirred at 20 °C for 12 h. LCMS showed that the reaction was complete, and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by preparative HPLC (FA conditions) to give the pure product. (R)-4-(4-(4-((1-(4-((2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 26 ) was obtained as a yellow solid (0.0275 g, 33.62 µmol, 23.10% yield, 97.42% purity). LCMS (ESI ⁺ ) m/z 797.5 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.79 (s, 1H), 10.27 - 9.92 (m, 1H), 8.81 (s, 1H), 7.92 (br d, J = 6.6 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 7.12 (d, J = 8.6 Hz, 2H), 6.95 - 6.87 (m, 4H), 5.72 - 5.61 (m, 1H), 5.05 (br s, 1H), 4.99 (br d, J = 10.4 Hz, 1H), 4.85 (br d, J = 17.1 Hz, 1H), 3H), 4.81 - 4.70 (m, 1H), 4.61 - 4.51 (m, 1H), 3.67 - 3.58 (m, 4H), 3.01 - 2.93 (m, 1H), 2.86 - 2.66 (m, 10H), 2.61 (br dd, J = 4.4, 16.6 Hz, 3H), 2.20 (ddd, J =13.5, 8.2, 5.8 Hz, 1H), 2.01 (ddd, J =13.3, 8.3, 5.2 Hz, 1H), 1.94 - 1.86 (m, 5H), 1.70 (br dd, J =13.7, 7.3 Hz, 1H), 1.43 - 1.30 (m, 4H), 0.87 (t, J = 7.4 Hz, 3H). Example 27 : 3-[4-[4-[4-[4-[[2-allyl-1-[(7S)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin- -1-yl]butylamino]phenyl]piperidin-2,6-dione ( Compound 27 )

4-[4-[4-[[2-allyl-1-[(7R)-7 _- ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin-2-yl] was added to the mixture at 20 °C under N2. To a solution of 3-(4- aminophenyl )piperidine-2,6-dione (commercially available) (41.50 mg, 203.21 µmol), NaBH(OAc) ₃ (43.07 mg, 203.21 µmol) in THF (2 mL) was added 1-( 4 -aminophenyl)butyraldehyde (intermediate 38 ) (0.082 g, 101.60 µmol, 72.20% purity) over 2 h. LCMS showed that the starting material was completely consumed. The mixture was concentrated in vacuo to give a residue which was purified by preparative HPLC to provide 3-[4-[4-[4-[4-[[2-allyl-1-[(7S)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]piperidin-2-yl as a yellow solid. -1-yl]butylamino]phenyl]piperidine-2,6-dione ( Compound 27 ) (0.021 g, 25.92% yield, 96.67% purity). LCMS (ESI ⁺ ) m/z 771.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.72 (br s, 1H), 10.12 (br s, 1H), 8.82 (s, 1H), 7.97 - 7.83 (m, 1H), 7.69 (br d, J = 8.1 Hz, 1H), 7.57 (br s, 2H), 6.96 - 6.85 (m, 4H), 6.52 (br d, J = 8.1 Hz, 2H), 5.76 - 5.59 (m, 1H), 5.52 (br t, J = 4.8 Hz, 1H), 5.05 (s, 1H), 4.99 (br d, J = 10.1 Hz, 1H), 4.85 (br d, J = 17.1 Hz, 1H), 4.80 - 4.70 (m, 1H), 4.62 - 4.51 (m, 1H), 3.63 (br dd, J = 10.3, 4.9 Hz, 1H), 3.09 (br s, 4H), 3.00 (m, 4H), 2.83 - 2.72 (m, 1H), 2.69 - 2.56 (m, 2H), 2.45 (br s, 1H), 2.41 (br s, 1H), 2.35 (br s, 2H), 2.25 - 2.15 (m, 1H), 2.13 - 1.95 (m, 4H), 1.93 - 1.83 (m, 1H), 1.70 (qd, J = 13.7, 6.9 Hz, 1H), 1.57 (br s, 4H), 0.87 (br t, J = 7.3 Hz, 3H). Example 28 : 3-((4-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)-4-hydroxypiperidin-1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 28 )

At 20 °C, 4-[[4-(4-aminophenyl)piperidin To a solution of (7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-methanesulfonyl-pyrazolo[3,4-d]pyrimidin-3 - one ( 166.57 mg, 400.93 µmol) in DMF (1.5 mL) was added DIEA (51.82 mg, 400.93 µmol, 69.83 µL). The mixture was stirred at 20 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was filtered and the filter was concentrated to give a residue. The residue was purified by preparative HPLC (FA conditions) to provide 3-((4-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-2-yl as a white solid. (40.0 mg, 22.95% yield , 95.23% purity). LCMS (ESI ⁺ ) m/z 414.8 [M/2+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.76 (s, 1H), 10.23 - 10.00 (m, 1H), 8.82 (s, 1H), 7.98 - 7.89 (m, 1H), 7.69 (d, J = 8.2 Hz, 1H), 7.65 - 7.47 (m, 2H), 6.91 (br d, J = 8.9 Hz, 2H), 6.76 (d, J = 8.8 Hz, 2H), 6.60 (d, J = 8.9 Hz, 2H), 5.67 (tdd, J = 5.9, 10.6, 16.8 Hz, 1H), 5.34 (d, J = 7.1 Hz, 1H), 3.0 (s, 1H), 4.91 (d, J = 10.1 Hz, 1H), 4.85 (br d, J = 17.5 Hz, 1H), 4.84 (m, 1H), 4.75 (br dd, J = 4.1, 14.9 Hz, 1H), 4.19 (ddd, J = 4.8, 6.8, 11.2 Hz, 1H), 4.23 (s, 1H), 3.19 (td, J = 4.2, 17.6 Hz, 1H), 3.23 (s, 2H), 3.20 (ddd, J = 4.7, 14.9 Hz, 1H), 8.1, 13.4 Hz, 1H), 2.15 - 2.06 (m, 1H), 2.01 (ddd, J = 5.4, 8.4, 13.4 Hz, 1H), 1.96 - 1.77 (m, 2H), 1.76 - 1.64 (m, 3H), 1.61 - 1.52 (m, 2H), 0.87 (t, J = 7.5 Hz, 3H). Example 29 : 3-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenethyl)-1,4-diazo -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 29 )

2-[4-[[2-allyl-1-[(7R)-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl methanesulfonate ( Intermediate 43 ) (160.0 mg, 290.58 µmol) and 3-[4-(1,4-diazo -1-yl)anilino]piperidin-2,6-dione ( intermediate 44 ) (141.5 mg, 435.87 µmol) was added to di To a solution of 4-nitropropane (5 mL) at 25 °C under _N2 was added DIEA (75.1 mg, 581.15 µmol) and NaI (4.4 mg, 29.06 µmol) in batches. The mixture was stirred at 100 °C for 12 h. LCMS showed that the reaction was complete and the desired product was detected. The mixture was concentrated at 40 °C under reduced pressure to give the crude product. The crude product was purified by preparative HPLC ( _NH4HCO3 conditions) to provide compound 29 (22.0 mg, _8.45 %). LCMS (ESI ⁺ ) m/z 757.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H), 10.43 - 9.95 (m, 1H), 8.87 (s, 1H), 7.92 (d, J = 8.1 Hz, 1H), 7.76 - 7.55 (m, 3H), 7.17 (br d, J = 8.4 Hz, 2H), 6.65 - 6.58 (m, 2H), 6.58 - 6.51 (m, 2H), 5.75 - 5.60 (m, 1H), 5.13 - 5.03 (m, 2H), 5.00 (d, J = 10.1 Hz, 1H), 4.86 (br d, J = 17.5 Hz, 3H), 2.63 - 2.56 (m, 3H), 2.26 - 2.17 ( m, 1H), 2.16 - 2.09 (m, 1H), 2.03 - 2.91 (m, 1H), 2.83 - 2.73 (m, 3H), 2.72 - 2.64 (m, 5H), 2.63 - 2.56 (m, 3H), 2.26 - 2.17 (m, 1H), 2.16 - 2.08 (m, 1H), 2.03 - 2.91 (m, 1H), 2.83 - 2.73 (m, 3H), 2.72 - 2.64 ( m , 5H), (m, 4H), 1.71 (qd, J = 13.9, 7.1 Hz, 1H), 0.87 (t, J = 7.3 Hz, 3H). Example 30 : 3-((4-(4-((R)-2-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)-2-hydroxyethyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 30 )

At 20°C, 3-(4-piperidin To a solution of (R)-2-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)-2-hydroxyethyl methanesulfonate ( Intermediate 47 ) (138.01 mg, 119.67 µmol) and TEA (36.33 mg, 359.02 µmol, 49.97 uL) in THF (1 mL) was added. The mixture was then stirred at 65 °C under _N2 for 24 h. LCMS showed the reaction was complete and the desired product was detected. The mixture was concentrated in vacuo to give a residue . The residue was purified by preparative HPLC (FA conditions) to provide compound 30 (9.1 mg, 9.69%). LCMS (ESI ⁺ ) m/z 759.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H), 10.24 (br s, 1H), 8.88 (s, 1H), 7.91 (d, J = 8.1 Hz, 1H), 7.70 (dd, J = 8.3, 3.6 Hz, 3H), 7.31 (d, J = 8.5 Hz, 2H), 6.75 (d, J = 8.9 Hz, 2H), 6.61 (d, J = 8.9 Hz, 2H), 5.78 - 5.55 (m, 1H), 5.37 (br d, J = 7.1 Hz, 1H), 5.13 - 4.93 (m, 3H), 4.86 (dd, J = 7.1, 1.1 Hz, 1H), 4.71 (br dd, J = 7.8, 4.7 Hz, 2H), 4.58 (br d, J = 6.1 Hz, 1H), 4.25 - 4.11 (m, 1H), 3.03 - 2.82 (m, 5H), 2.81 - 2.67 (m, 2H), 2.62 (br s, 4H), 2.59 - 2.51 (m, 2H), 2.43 (br dd, J = 12.6, 4.5 Hz, 1H), 2.25 - 2.15 (m, 1H), 2.14 - 2.09 (m, 1H), 2.18 (br d, J = 5.1 Hz, 1H), 1.95 - 1.77 (m, 2H), 1.76 - 1.64 (m, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 31 : 3-((4-(4-((S)-2-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)-2-hydroxyethyl)piperidin -1-yl)phenyl)amino)piperidin-2,6-dione ( Compound 31 )

Compound 31 ( 5 % yield) was synthesized from 3-(4-piperidin- -1-ylanilino)piperidine-2,6-dione and intermediate 48. LCMS (ESI ⁺ ) m/z 759.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.76 (br s, 1H), 10.25 (br s, 1H), 8.88 (s, 1H), 7.91 (br d, J = 8.1 Hz, 1H), 7.69 (br dd, J = 8.1, 3.3 Hz, 3H), 7.31 (br d, J = 8.5 Hz, 2H), 6.75 (br d, J = 8.7 Hz, 2H), 6.60 (br d, J = 8.7 Hz, 2H), 5.75 - 5.60 (m, 1H), 5.38 (br d, J = 7.3 Hz, 1H), 5.08 (s, 1H), 5.01 (br dd, J = 8. d, J = 10.1 Hz, 2H), 4.85 (br d, J = 17.2 Hz, 1H), 4.80 - 4.67 (m, 2H), 4.56 (br dd, J = 16.2, 5.9 Hz, 1H), 4.23 - 4.13 (m, 1H), 2.93 (br s, 5H), 2.81 - 2.68 (m, 3H), 2.66 - 2.57 (m, 4H), 2.57 - 2.53 (m, 1H), 2.43 (br dd, J = 12.6, 4.4 Hz, 1H), 2.24 - 2.15 (m, 1H), 2.14 - 2.09 (m, 1H), 2. (ddd, J =13.2, 8.2, 5.4 Hz, 1H), 1.94 - 1.77 (m, 2H), 1.75 - 1.64 (m, 1H), 0.86 (br t, J = 7.3 Hz, 3H). Example 32 : 3-((4-(4-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)piperidin-1-yl)phenyl)amino)piperidine-2,6-dione ( Compound 32 )

Compound 32 (30% yield) was synthesized from intermediate 50 and (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-(methylsulfonyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one using 2-propanol as solvent in the presence of DIEA at 20 °C for 12 h. LCMS (ESI ⁺ ) m/z 812.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (br s, 1H), 10.21 - 9.98 (m, 1H), 8.81 (s, 1H), 7.93 (br d, J = 7.4 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 6.92 (br d, J = 9.0 Hz, 2H), 6.75 (d, J = 8.9 Hz, 2H), 6.60 (d, J = 8.9 Hz, 2H), 5.67 (tdd, J = 16.8, 10.5, 6.0 Hz, 1H), 5.35 (d, J = 7.3 Hz, 5H), 4.86 (br d, J = 17.0 Hz, 1H), 4.84 (br dd, J = 15.7, 5.4 Hz, 1H), 4.18 (ddd, J = 11.3, 6.9, 4.9 Hz, 1H), 3.59 (br d, J = 12.3 Hz, 2H), 3.36 (br s, 3H), 3.04 - 2.91 (m, 1H), 2.83 - 2.62 (m, 6H), 2.61 - 2.51 (m, 3H), 2.26 - 2.16 (m, 1H), 2.14 - 2.06 (m, 1H), 2.01 (ddd, J = 13.4, 8.4, 5.3 Hz, 1H), 1.94 - 1.78 (m, 6H), 1.70 (dd, J = 13.6, 7.3 Hz, 1H), 1.42 - 1.28 (m, 4H), 0.87 (t, J = 7.4 Hz, 3H) Example 33 ：3-(3-((6-((4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)methyl)-2-azaspiro[3.3]hept-2-yl)methyl)phenyl)piperidin-2,6-dione ( Compound 34 )

Compound 40 (10% yield) was synthesized from intermediate 8 and intermediate 51 by following a similar procedure as described for the synthesis of compound 29 in Example 29. LCMS (ESI ⁺ ) m/z 823.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.85 (s, 1H), 10.33 - 10.01 (m, 1H), 8.84 (s, 1H), 8.36 (s, 2H), 7.90 (br d, J = 8.1 Hz, 1H), 7.73 - 7.61 (m, 3H), 7.31 - 7.21 (m, 2H), 7.17 (s, 1H), 7.11 - 6.99 (m, 3H), 5.67 (tdd, J = 16.8, 10.7, 5.9 Hz, 1H), 5.00 (d, J = 9.8 Hz, 1H), 4.86 (br d, J = 17.3 Hz, 3.77 (m, 7H), 3.67 (s, 2H), 3.54 - 3.56 (m, 4H), 3.03 - 2.91 (m, 1H), 2.83 - 2.73 (m, 1H), 2.65 (ddd, J = 17.1, 11.5, 5.6 Hz, 1H), 2.54 - 2.56 (m, 1H), 2.47 (s, 2H), 2.25 - 2.11 (m, 2H), 2.18 - 2.22 (m, 2H), 2.30 - 2.54 (m, 4H), 2.71 - 2.81 (m, 1H), 2.8 dH), 1.99 - 1.93 (m, 2H), 1.93 - 1.84 (m, 1H), 1.80 - 1.66 (m, 3H), 0.87 (t, J = 7.4 Hz, 3H). Example 34 : 3-(4-(2-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)ethyl)phenyl)piperidin-2,6-dione ( Compound 34 )

Compound 34 (21% yield) was synthesized from intermediate 52 and (R)-2-allyl-1-(7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-6-(methylsulfonyl)-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one in the presence of _i- PrOH at 80 °C under N2 for 12 h. LCMS (ESI ⁺ ) m/z 728.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.81 (s, 1H), 10.18 - 10.06 (m, 1H), 8.82 (s, 1H), 7.93 (br d, J = 7.1 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.58 (br s, 2H), 7.24 - 7.17 (m, 2H), 7.17 - 7.09 (m, 2H), 6.93 (br d, J = 8.9 Hz, 2H), 5.67 (tdd, J = 16.8, 10.6, 5.9 Hz, 1H), 5.05 (s, 1H), 5.02 - 4.97 (m, 1H), 4.85 (br d, J = 17.1 Hz, 1H), 4.81 - 4.67 (m, 1H), 4.63 - 4.51 (m, 1H), 3.81 (dd, J = 11.3, 4.9 Hz, 1H), 3.11 (br s, 4H), 3.02 - 2.92 (m, 1H), 2.83 - 2.73 (m, 3H), 2.71 - 2.64 (m, 1H), 2.64 - 2.56 (m, 6H), 2.48 - 2.44 (m, 1H), 2.25 - 2.12 (m, 2H), 2.07 - 1.97 (m, 2H), 1.94 - 1.83 (m, 1H), 1.76 - 1.65 (m, 1H), 0.87 (t, J = 7.4 Hz, 3H). Example 35 : 3-(4-(4-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenethyl)amino)piperidin-1-yl)phenyl)piperidine-2,6-dione ( Compound 35 )

Compound 35 (19% yield) was synthesized from 3-[4-(4-amino-1-piperidinyl)phenyl]piperidine-2,6-dione ( Intermediate 13 ) and 2-[4-[[2 - allyl - 1 -[( 7R )-7-ethyl-7-hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-3-oxo-pyrazolo[3,4-d]pyrimidin-6-yl]amino]phenyl]ethyl methanesulfonate ( Intermediate 43 ) by following a similar procedure as described for the synthesis of compound 29 in Example 29 using DMF as solvent. LCMS (ESI ⁺ ) m/z 742.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.76 (br s, 1H), 10.20 (br d, J =2.50 Hz, 1H), 8.87 (s, 1H), 7.91 (d, J =8.13 Hz, 1H), 7.62-7.72 (m, 3H), 7.18 (br d, J =8.25 Hz, 2H), 7.02 (d, J =8.50 Hz, 2H), 6.87 (d, J =8.63 Hz, 2H), 5.59-5.74 (m, 1H), 5.06 (s, 1H), 5.00 (br d, J =10.26 Hz, 1H), 4.86 (br d, J =17.13 Hz, 1H), 4.75 (br dd, J =15.13, 3.50 Hz, 1H), 4.56 (br dd, J =15.95, 6.19 Hz, 1H), 3.71 (br dd, J =10.82, 4.94 Hz, 1H), 3.57 (br s, 2H), 2.92-3.01 (m, 1H), 2.75-2.82 (m, 3H), 2.73 (br d, J =5.88 Hz, 1H), 2.63-2.71 (m, 4H), 2.56-2.63 (m, 2H), 2.41-2.47 (m, 1H), 2.14-2.24 (m, 1H), δ 2.08-2.14 (m, 1H), 1.97-2.07 (m, 2H), 1.84-1.92 (m, 3H), 1.70 (dq, J =13.91, 7.12 Hz, 1H), 1.25-1.37 (m, 2H), 0.87 (t, J =7.32 Hz, 3H). Example 36 : 3-(4-(4-((3-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)azine-1-yl)methyl)piperidin-1-yl)phenyl)piperidin-2,6-dione ( Compound 36 )

Compound 36 (9% yield) was synthesized from intermediate 53 and intermediate 8 by following a similar procedure as described for the synthesis of compound 33 in Example 33. LCMS (ESI ⁺ ) m/z 852.5 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.75 (s, 1H), 10.17 - 10.01 (m, 1H), 8.81 (s, 1H), 7.93 (br d, J = 7.9 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.58 (br d, J = 4.4 Hz, 2H), 7.03 (d, J = 8.6 Hz, 2H), 6.90 (br dd, J = 13.8, 8.9 Hz, 4H), 5.74 - 5.57 (m, 1H), 5.07 - 4.91 (m, 2H), 4.85 (br d, J = 17.4 Hz, 1H), 3H), 3.77 - 3.61 (m, 3H), 3.54 (br dd, J = 17.9, 10.4 Hz, 2H), 3.02 - 2.96 (m, 1H), 2.87 - 2.71 (m, 5H), 2.71 - 2.57 (m, 4H), 2.49 - 2.41 (m, 2H), 2.36 - 2.25 (m, 2H), 2.25 - 2.12 (m, 5H), 2.09 (br dd, J = 11.6, 3.4 Hz, 1H), 2.10 - 2.16 (m , 3H), 2. 5.4 Hz, 2H), 1.89 (qd, J = 13.9, 7.1 Hz, 1H), 1.84 - 1.59 (m, 5H), 1.28 - 1.14 (m, 2H), 0.87 (t, J = 7.4 Hz, 3H). Example 37 : 3-(4-((6-((4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin- -1-yl)methyl)-2-azaspiro[3.3]hept-2-yl)methyl)phenyl)piperidin-2,6-dione ( Compound 37 )

Compound 37 (4% yield) was synthesized from intermediate 55 and intermediate 8 by following a similar procedure as described for the synthesis of compound 33 in Example 33. LCMS (ESI ⁺ ) m/z 823.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 11.05 - 10.53 (m, 1H), 10.31 - 10.06 (m, 1H), 8.84 (d, J = 1.3 Hz, 1H), 7.95 - 7.87 (m, 1H), 7.75 - 7.59 (m, 3H), 7.29 (d, J = 8.0 Hz, 1H), 7.20 (br d, J = 8.6 Hz, 1H), 7.18 - 7.08 (m, 2H), 7.02 (br d, J = 8.8 Hz, 2H), 5.75 - 5.59 (m, 1H), 5.00 (br d, J = 10.4 Hz, 3.74 (m, 6H), 3.68 (br s, 1H), 3.66 (s, 2H), 3.48 (br d, J = 4.0 Hz, 3H), 3.42 (br s, 2H), 3.21 - 3.12 (m, 2H), 3.02 - 2.91 (m, 1H), 2.84 - 2.73 (m, 1H), 2.65 - 2.58 (m, 6H), 3.88 - 3.74 (m, 6H), 3.68 (br s, 1H), 3.66 (s, 2H), 3.48 (br d, J = 4.0 Hz, 3H), 3.42 (br s, 2H), 3.21 - 3.12 (m, 2H), 3.02 - 2.91 (m, 1H), 2.84 - 2.73 (m, 1H), 9 - 1.54 (m, 2H), 3.73 - 3.77 (m, 1H), 1.62 - 1.81 (m, 3H), 1.91 - 1.84 (m, 2H), 1.70 - 1.89 (m, 1H), 0.85 (t, J = 7.4 Hz, 3H). Example 38 : 3-(4-((3-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)propyl)amino)phenyl)piperidin-2,6-dione ( Compound 38 )

Compound 38 ( 12% yield) was synthesized from intermediate 56 and 2- allyl -1-[(7R)-7- ethyl -7 - hydroxy-5,6-dihydrocyclopenta[b]pyridin-2-yl]-6-(4-piperidin-2-yl) ... -1-ylanilino)pyrazolo[3,4-d]pyrimidin-3-one. LCMS (ESI ⁺ ) m/z 757.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.73 (s, 1H), 10.24 - 9.99 (m, 1H), 8.83 (s, 1H), 7.94 (br d, J = 5.7 Hz, 1H), 7.70 (d, J = 8.2 Hz, 1H), 7.59 (br d, J = 4.6 Hz, 2H), 7.00 - 6.83 (m, 4H), 6.53 (d, J = 8.5 Hz, 2H), 5.77 - 5.53 (m, 2H), 5.08 - 4.96 (m, 2H), 4.91 - 4.82 (m, 1H), 4.81 - 4.70 (m, 1H), 3H), 4.63 - 4.53 (m, 1H), 3.64 (dd, J = 10.5, 5.1 Hz, 1H), 3.12 (br s, 4H), 3.06 (q, J = 6.2 Hz, 2H), 3.02 - 2.93 (m, 1H), 2.83 - 2.74 (m, 1H), 2.66 - 2.58 (m, 1H), 2.54 (br s, 4H), 2.48 - 2.41 (m, 3H), 2.25 - 2.16 (m, 1H), 2.12 - 1.96 (m, 3H), 1.73 - 1.81 (m, 1H), 1.89 (qd, J = 14.0, 6.9 Hz, 2H 3H), 0.88 (t, J = 7.4 Hz, 3H). Example 39 : 3-(4-(((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)methyl)phenyl)piperidine-2,6-dione ( Compound 39 )

To a mixture of intermediate 36 (0.08 g, 105.26 µmol) in MeOH (2 mL), intermediate 54 (27.44 mg, 126.31 µmol), AcOH (6.32 mg, 105.26 µmol, 6.03 µL), and NaBH ₃ CN (7.94 mg, 126.31 µmol) were added, and the mixture was stirred at 20 °C under N ₂ for 1 h. LCMS showed that the starting material was completely consumed and the desired product was formed. The mixture was purified by preparative HPLC purification ( FA conditions) to provide compound 39 (19.0 mg, 24.76%). LCMS (ESI ⁺ ) m/z 728.4 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.85 (s, 1H), 10.21 - 10.05 (m, 1H), 8.82 (s, 1H), 8.23 (s, 1H), 8.03 - 7.82 (m, 1H), 7.70 (d, J = 8.1 Hz, 1H), 7.57 (br d, J = 1.7 Hz, 2H), 7.35 (d, J = 7.9 Hz, 2H), 7.19 (d, J = 8.0 Hz, 2H), 6.93 (br d, J = 8.9 Hz, 2H), 5.74 - 5.61 (m, 1H), 5.20 - 5.02 (m, 1H), d, J = 11.9 Hz, 2H), 3.03 - 2.92 ( m , 1H), 2.84 - 2.74 (m, 1H), 2.73 - 2.58 (m, 4H), 2.49 - 2.44 (m, 1H), 2.27 - 2.11 ( m, 2H), 2.18 - 2.30 (m, 2H), 2.16 - 2.43 (m, 4H), 2.23 - 2.19 (m, 2H), 2.30 - 2.54 (m, 4H), 2.54 - 2.83 (m, 2H), 2.16 - 2.21 (m, 2H), 2.23 - 2.83 (m, 2H), 2.29 - 2.30 (m, 4H), 2. 5H), 1.71 (qd, J = 13.8, 7.0 Hz, 1H), 1.46 (q, J = 10.1 Hz, 2H), 0.88 (t, J = 7.3 Hz, 3H). Example 40 : 3-(4-(2-((1-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin-4-yl)amino)ethyl)phenyl)piperidine-2,6-dione ( Compound 40 )

Compound 40 (15% yield) was synthesized from intermediate 57 and 2- allyl -6-[4-(4-amino-1-piperidinyl)anilino]-1-[(7S)-7-ethyl- 7 -hydroxy- 5,6 -dihydrocyclopenta[b]pyridin-2-yl]pyrazolo[3,4-d]pyrimidin-3-one ( intermediate 36 ) by following a similar procedure as described for the synthesis of compound 29 in Example 29. LCMS (ESI ⁺ ) m/z 742.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.82 (br s, 1H), 10.23 - 10.02 (m, 1H), 8.81 (s, 1H), 7.93 (br d, J = 6.7 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.56 (br s, 2H), 7.29 - 7.08 (m, 4H), 6.92 (br d, J = 8.9 Hz, 2H), 5.66 (tdd, J = 16.8, 10.5, 5.9 Hz, 1H), 5.17 - 5.02 (m, 1H), 4.93 (dd, J = 10.2, 0.9 Hz, 3H), 2.75 - 2.57 ( m , 6H), 2.49 - 2.43 (m, 2H) , 2.26 - 2.10 (m, 2H), 2.03 - 1.97 (m, 2H), 1.83 - 1.81 (m, 3H), 1.92 - 1.83 (m, 4H), 1.28 - 1.30 (m, 4H), 1.11 - 1.28 (m, 4H), 1.54 - 1.61 (m, 4H), 1.23 - 1.83 (m, 2H), 1.28 - 1.97 (m, 2H), 1.83 - 1.81 (m, 4H), 1.28 - 1.83 (m, 4H), (m, 3H), 1.76 - 1.64 (m, 1H), 1.38 (q, J = 10.0 Hz, 2H), 0.87 (t, J = 7.4 Hz, 3H). Example 41 : 3-(4-((2-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)ethyl)amino)phenyl)piperidin-2,6-dione ( Compound 41 )

Compound 41 (25% yield) was synthesized by following a similar procedure as described for the synthesis of compound 38 , using 2-((4-(2,6-dioxopiperidin-3-yl)phenyl)amino)ethyl methanesulfonate ( intermediate 58 ) instead of 3-((4-(2,6-dioxopiperidin-3-yl)phenyl)amino)propyl methanesulfonate. LCMS (ESI ⁺ ) m/z 743.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.73 (br s, 1H), 10.12 (br s, 1H), 8.82 (s, 1H), 7.92 (br d, J = 5.1 Hz, 1H), 7.69 (br d, J = 8.1 Hz, 1H), 7.58 (br s, 2H), 6.92 (br d, J = 7.4 Hz, 4H), 6.56 (br d, J = 7.9 Hz, 2H), 5.75 - 5.59 (m, 1H), 5.37 (br s, 1H), 5.05 (s, 1H), 4.99 (br d, J = 10.3 Hz, 1H), 4.85 (br d, J = 17.1 Hz, 1H), 4.80 - 4.69 (m, 1H), 4.62 - 4.51 (m, 1H), 3.64 (br dd, J = 9.9, 4.4 Hz, 1H), 3.12 (br s, 6H), 3.04 - 2.89 (m, 2H), 2.83 - 2.72 (m, 1H), 2.58 (br s, 7H), 2.47 - 2.39 (m, 1H), 2.19 (br d, J = 5.6 Hz, 1H), 2.14 - 1.97 (m, 3H), 1.94 - 1.85 (m, 1H), 1.70 (br dd, J = 13.6,7.1 Hz, 1H), 0.87 (br t, J = 6.9 Hz, 3H). Example 42 : 3-(4-(3-(4-(4-((2-allyl-1-((R)-7-ethyl-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-2-yl)-3-oxo-2,3-dihydro-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)phenyl)piperidin -1-yl)propyl)phenyl)piperidin-2,6-dione ( Compound 42 )

Compound 42 (51% yield) was synthesized from intermediate 60 and 2- allyl -1-[(7R)-7-ethyl-7 - hydroxy-5,6-dihydrocyclopenta[b]pyridin- 2 -yl]-6-(4-piperidin-2-yl) ... -1-ylanilino)pyrazolo[3,4-d]pyrimidin-3-one ( Intermediate 8 ). LCMS (ESI ⁺ ) m/z 742.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 10.81 (s, 1H), 10.22 - 9.99 (m, 1H), 8.82 (s, 1H), 7.93 (br d, J = 7.1 Hz, 1H), 7.69 (d, J = 8.1 Hz, 1H), 7.58 (br s, 2H), 7.21 - 7.16 (m, 2H), 7.15 - 7.10 (m, 2H), 6.92 (br d, J = 8.9 Hz, 2H), 5.74 - 5.59 (m, 1H), 5.08 (s, 1H), 4.99 (d, J = 9.9 Hz, 1H), 4.85 (br d, J = 8. = 17.0 Hz, 1H), 4.81 - 4.68 (m, 1H), 4.56 (br dd, J = 15.4, 5.4 Hz, 1H), 3.81 (dd, J = 11.2, 4.9 Hz, 1H), 3.10 (br s, 4H), 3.03 - 2.90 (m, 1H), 2.84 - 2.73 (m, 1H), 2.71 - 2.56 (m, 3H), 2.55 - 2.51 (m, 4H), 2.47 - 2.43 (m, 1H), 2.35 (br t, J = 7.1 Hz, 2H), 2.24 - 2.11 (m, 2H), 2.19 - 2.28 (m, 2H), 1.95 - 1.83 (m, 1H), 1.83 - 1.65 (m, 3H), 0.87 (t, J = 7.4 Hz, 3H). Example A MOLT-4 and A-427 cell proliferation assay

Cell proliferation was measured using the CellTiter-Glo® Luminescent Cell Viability Assay. The assay involves the addition of a single reagent (CellTiter-Glo® Reagent) directly to cells cultured in serum-supplemented medium. MOLT-4 cells (ATCC, CRL-1582) and A427 cells (ATCC, HTB-53) were cultured according to ATCC recommendations and seeded at 6,000 cells per well (for MOLT-4) and 3,000 cells per well (for A427).

Each compound evaluated was prepared as a DMSO stock solution (10 mM). Compounds were tested in duplicate on each plate using a 10-point continuous dilution curve (1:3 dilution). The highest compound concentration was 10 µM (final) with a 0.1% final DMSO concentration. The plates were then incubated at 37°C, 5% CO ₂ for 72 hours, followed by equilibration at room temperature for approximately 30 minutes. An equal volume of CellTiter-Glo® reagent (100 µL) was added to each well. The plates were mixed on an orbital shaker for 2 mins to induce cell lysis, followed by incubation at rt for 10 minutes to stabilize the luminescence signal. Luminescence was recorded using a Spectramax i3x (Molecular Devices) plate reader according to the CellTiter-Glo protocol. IC50 determinations were performed using nonlinear regression, variable slope (four parameters), inhibitor v. reaction equation (Prism 9.0). _IC50 values are provided in Table 1. For comparison, Table 1 also includes the _IC50 value of compound ZN-c3. Table 1 Example# MOLT-4 (nM) A427 (nM) 1 ND C 2 ND B 3 ND C 4 ND B 5 A C 6 A A 7 A A 8 A A 9 A A 10 A A 11 ND A 12 C C 13 A C 14 A A 15 A A 16 A A 17 B C 18 A A 19 C C 20 ND A twenty two A A twenty three ND A 24A A A 24B A A 25 ND A 26 ND A 27 A A 28 ND A 29 A B 30 A B 31 A C 32 A A 33 C C 34 A A 35 A B 36 A B 37 C C 38 A A 39 A A 40 A A 41 A A 51 A A ZN-c3 B B IC ₅₀ for MOLT-4 and A427 CTG: A = single IC ₅₀ ≤ 100 nM; B = single IC ₅₀ >100 nM and < 200 nM; C = single IC ₅₀ ≥200 nM; ND = not determined B Protein degradation assay in MOLT-4 cells

One million MOLT-4 cells (ATCC, CRL-1582) were incubated with vehicle (DMSO) or 10 µM, 1 µM, 0.1 µM, or 0.01 µM concentrations of the indicated compounds for 5 h. After treatment, cells were harvested in RIPA lysis buffer supplemented with 1% phosphatase inhibitor and protease inhibitor cocktail, and protein concentrations were determined by BCA assay. Equal amounts of protein (4.5 µg/lane) from each cell extract were loaded onto a 12-230 kDa Separation 25 capillary cartridge from ProteinSimple and probed with antibodies against WEE1 (1:200 dilution, final concentration 1 µg/mL) and β-actin (1:500 dilution, final concentration 0.6 µg/mL) on the ProteinSimple Jess system according to the ProteinSimple/SimpleWestern protocol. The area under the curve (AUC) from the resulting electropherograms of each protein peak at the tested concentrations was used to calculate the remaining percentage of WEE1 using the equation remaining percentage = 100*(WEE1/β-actin)/(WEE1 _DMSO /β-actin _DMSO ). For illustrative purposes, electropherograms were exported as virtual ink dots using Compass (ProteinSimple) for SW v 6.0. WEE-1 antibody (sc-5285) was purchased from Santa Cruz Biotechnology, and β-actin (MAB8929) was purchased from R&D Systems. The remaining percentage of WEE1 after 5 hours of treatment in MOLT-4 cells at the tested concentrations is provided in Table 2.

The ability of heterobifunctional degraders to degrade the protein of interest (POI) depends on the efficient formation of a ternary complex in a 1:1:1 ratio between the POI, the compound, and the E3 ligase. At high compound concentrations, a phenomenon known as the "hook effect" occurs when the POI and E3 binding sites are saturated, resulting in the POI and E3 proteins being bound by different degrader compounds to form separate binary complexes. In this case, a 1:1:1 ternary complex cannot be effectively formed between the POI and E3, and degradation losses are observed. The "hook effect" was observed for several compounds at higher concentrations, however, these results indicate that many of the exemplary compounds are potent degraders of WEE1. Table 2 The remaining percentage of WEE1 in MOLT-4 cells after 5 hours Example# 0.01 µM 0.1 µM 1 µM 10 µM 1 C A B C 2 A A A B 3 C B C C 4 A A A C 5 B A A B 6 A A A B 7 A A A C 8 A A A C 9 A A A B 10 A A A C 11 A A A B 12 C C C C 13 B A A C 14 A A B C 15 A A A B 16 A A A B 17 B A C C 18 A A A C 19 C C C C 20 C C C ND twenty three C C C ND 25 C C C ND 26 C C C ND 32 A A A A 34 A A A C 35 A A A C WEE1 degradation assay in MOLT-4 cells: A = <30%; B = 30 to 60%; C = >60%; ND = not determined. Example C HiBiT assay to evaluate degradation of novel substrates for IKZF1 and GSPT1

Heterobifunctional degraders containing glutarimide are known to bind additional proteins due to neomorphic interactions with E3 ligases. Degradation of neosubstrates is monitored, as degradation of these additional targets may increase efficacy or promote undesirable off-target effects. Evaluation of two well-documented neosubstrates, IKZF1 and GSPT1, is described using the HiBiT assay.

5x10 ⁴ JURKAT-IKZF1-HiBiT (Promega CS3023169) or 5x10 ⁴ HEK-293-GSPT1-HiBiT (Promega CS3023105) were seeded in 90 µL volume into the wells of a white flat opaque bottom 96-well plate and incubated at 37°C and 5% CO2 for 1 hour (IKFZ1) or overnight (GSPT1). RPMI-1640 + 10% FBS + 1% Pen/Strep + 200 µg/mL hygromycin (IKZF1) or DMEM + 10% FBS + 1% Pen/Strep + 200 µg/mL hygromycin (GSPT1) constituted the complete medium. One hour prior to compound treatment, 90 µL of 100x Vivazine substrate (Promega N2581) diluted 1:50 in medium was added to each well. Cells were incubated for 1 hour at 37°C and 5% _CO2 , and baseline luciferase levels were recorded using a SpectraMax M5e Multi-Mode Microplate Reader. Cells were then treated with compounds in a 10-point semi-log serial dilution format starting at a high dose of 10 µM using a Pico8 and normalized to 0.1% DMSO between all doses. A 0.1% DMSO control was included. Total volume per well was 180 uL. Cells were incubated at 37°C and 5% _CO2 for 16 hours (IKZF1) or 24 hours (GSPT1). After the indicated incubation times, luciferase levels were read using a SpectraMax M5e multi-mode microplate reader according to the Cell-Titer Glo-Luminescence protocol. Data were corrected for background signal and initial inoculum level, and residual IKZF1 or GSPT1 protein was expressed as % relative to DMSO. _DC50 and _Dmax were determined using GraphPad Prizm software (v9.1).

Table 3 summarizes the DC ₅₀ and D _max of IKZF1 (16 h) and GSPT1 (24 h) protein degradation. Example# GSPT1 protein degradation (24 h) IKZF1 protein degradation (16 h) DC ₅₀ (nM) D _max (%) DC ₅₀ (nM) D _max (%) 1 C C C C 2 A C C A 3 C C C C 4 A C C C 5 A B C C 6 A B C B 7 A C C B 8 A C B C 9 A C B B 10 A C B C 11 A C C B 12 C C C C 13 B C B C 14 B C B C 15 A C C A 16 B C B B 17 A B B B 18 C B C B 19 A C C B 20 C C B C 30 B C C C 35 A C C A 39 A B C B 43 A C C B HiBiT protein degradation assay for GSPT1 and IKZF1 DC ₅₀ : A = <100 nM; B = 100 to 500 nM; C = >500 nM; D _max : A = >70%; B = 40 to 70%; C = <40%.

In addition, although the foregoing has been described in some detail by way of illustration and example for the purpose of clarity and understanding, a person skilled in the art will appreciate that various modifications can be made without departing from the spirit of the present disclosure. Therefore, it should be clearly understood that the form disclosed herein is only for illustration and is not intended to limit the scope of the present disclosure, but also covers all modifications and alternatives that come with the true scope and spirit of the present disclosure.

[Figure 1] shows a general synthesis scheme for preparing compounds of formula (I). [Figure 2] shows a general synthesis scheme for preparing examples of compounds of formula (I). [Figure 3] shows a general synthesis scheme for preparing examples of compounds of formula (I). [Figure 4] shows a synthesis scheme for preparing intermediate 1. [Figure 5] shows a synthesis scheme for preparing intermediate 2. [Figure 6] shows a synthesis scheme for preparing intermediate 3. [Figure 7] shows a synthesis scheme for preparing intermediate 4. [Figure 8] shows a synthesis scheme for preparing intermediate 5. [Figure 9] shows a synthesis scheme for preparing intermediate 6. [Figure 10] shows a synthesis scheme for preparing intermediate 7. [Figure 11] shows a synthesis scheme for preparing intermediate 8. [Figure 12] shows a synthesis scheme for preparing intermediate 9. [Figure 13] shows a synthesis scheme for preparing intermediate 10. [Figure 14] shows a synthesis scheme for preparing intermediate 12. [Figure 15] shows a synthesis scheme for preparing intermediate 13. [Figure 16] shows a synthesis scheme for preparing intermediate 14. [Figure 17] shows a synthesis scheme for preparing intermediate 15. [Figure 18] shows a synthesis scheme for preparing intermediate 16. [Figure 19] shows a synthesis scheme for preparing intermediate 17. [Figure 20] shows a synthesis scheme for preparing intermediate 18. [Figure 21] shows a synthesis scheme for preparing intermediate 19. [Figure 22] shows a synthesis scheme for preparing intermediate 21. [Figure 23] shows a synthesis scheme for preparing intermediate 22. [Figure 24] shows a synthesis scheme for preparing intermediate 23. [Figure 25] shows a synthesis scheme for preparing intermediate 24. [Figure 26] shows a synthesis scheme for preparing intermediate 25. [Figure 27] shows a synthesis scheme for preparing intermediate 26. [Figure 28] shows a synthesis scheme for preparing intermediate 27. [Figure 29] shows a synthesis scheme for preparing intermediate 28. [Figure 30] shows a synthesis scheme for preparing intermediate 29. [Figure 31] shows a synthesis scheme for preparing intermediate 30. [Figure 32] shows a synthesis scheme for preparing intermediate 31. [Figure 33] shows a synthesis scheme for preparing intermediate 33. [Figure 34] shows a synthesis scheme for preparing intermediate 34. [Figure 35] shows a synthesis scheme for preparing intermediate 35. [Figure 36] shows a synthesis scheme for preparing intermediate 36. [Figure 37] shows a synthesis scheme for preparing intermediate 37. [Figure 38] shows a synthesis scheme for preparing intermediate 38. [Figure 39] shows a synthesis scheme for preparing intermediate 40. [Figure 40] shows a synthesis scheme for preparing intermediate 43. [Figure 41] shows a synthesis scheme for preparing intermediate 44. [Figure 42] shows a synthesis scheme for preparing intermediates 47 and 48. [Figure 43] shows a synthesis scheme for preparing intermediate 50. [Figure 44] shows a synthesis scheme for preparing intermediate 51. [Figure 45] shows a synthesis scheme for preparing intermediate 52. [Figure 46] shows a synthesis scheme for preparing intermediate 53. [Figure 47] shows a synthesis scheme for preparing intermediate 54. [Figure 48] shows a synthesis scheme for preparing intermediate 55. [Figure 49] shows a synthesis scheme for preparing intermediate 56. [Figure 50] shows a synthesis scheme for preparing intermediate 57. [Figure 51] shows a synthesis scheme for preparing intermediate 58. [Figure 52] shows a synthesis scheme for preparing intermediate 60.

Claims (50)

A compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein the compound has the following structure: (I) wherein: ^R1 is absent, substituted or unsubstituted 6- to 10-membered aryl, -NH-(substituted or unsubstituted 6- to 10-membered aryl)-, substituted or unsubstituted 6- to 10-membered heteroaryl, -NH-(substituted or unsubstituted 6- to 10-membered heteroaryl)-, or -NH-(substituted or unsubstituted 6- to 10-membered cycloalkyl)-; ^R2 is absent, substituted or unsubstituted 4- to 10-membered heterocyclo, or -O-(substituted or unsubstituted 4- to 10-membered heterocyclo); ^R3 is absent, substituted or unsubstituted _C1 - _C6 alkylene, -NH-, -NH-(substituted or unsubstituted _C1 - _C6 alkylene)-, -O-(substituted or unsubstituted C1-C6 _alkylene )- R ⁴ is absent or a substituted or unsubstituted _{4- to 10} -membered heterocyclic group ^{; provided that at least two of R 1 , R 2} _, ^R ₃ ^, and R ⁴ are present; R ^C is or ; ^RD is substituted or unsubstituted C ₁ -C ₆ alkyl; and Y is -CH or N. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is absent. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is a substituted or unsubstituted 6- to 10-membered aryl group. The compound of claim 3 or a pharmaceutically acceptable salt thereof, wherein R ¹ is unsubstituted phenyl. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is -NH-(substituted or unsubstituted 6- to 10-membered aryl)-. The compound of claim 4 or a pharmaceutically acceptable salt thereof, wherein R ¹ is or . The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is a substituted or unsubstituted 5- to 10-membered heteroaryl group. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is -NH-(substituted or unsubstituted 5- to 10-membered heteroaryl)-. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R ¹ is -NH-(substituted or unsubstituted 6- to 10-membered cycloalkyl)-. The compound of claim 9 or a pharmaceutically acceptable salt thereof, wherein R ¹ is . The compound of any one of claims 1 to 10 or a pharmaceutically acceptable salt thereof, wherein R ² is absent. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 10, wherein R ² is a substituted or unsubstituted 4- to 10-membered heterocyclic group. The compound of claim 12 or a pharmaceutically acceptable salt thereof, wherein R ² is , , ,or . The compound of claim 12 or a pharmaceutically acceptable salt thereof, wherein R ² is or . The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 10, wherein R ² is -O-(substituted or unsubstituted 4- to 10-membered heterocyclic group). The compound of claim 15 or a pharmaceutically acceptable salt thereof, wherein R ² is . The compound or pharmaceutically acceptable salt thereof of any one of claims 1 to 16, wherein R ³ is absent. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 16, wherein R ³ is a substituted or unsubstituted C ₁ -C ₆ alkylene group. The compound of claim 18 or a pharmaceutically acceptable salt thereof, wherein R ³ is -(CH ₂ )-, -(CH ₂ CH ₂ )-, or -(CH ₂ CH ₂ CH ₂ )-. The compound of claim 18 or a pharmaceutically acceptable salt thereof, wherein R ³ is -(CH ₂ CH(OH))-. The compound or pharmaceutically acceptable salt thereof of any one of claims 1 to 16, wherein R ³ is -NH-. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 16, wherein R ³ is -NH-(substituted or unsubstituted C ₁ -C ₆ alkylene)-. The compound of claim 22 or a pharmaceutically acceptable salt thereof, wherein R ³ is -NH-(CH ₂ )-. The compound of claim 22 or a pharmaceutically acceptable salt thereof, wherein R ³ is -NH-(CH ₂ CH ₂ )-, -NH-(CH ₂ CH ₂ CH ₂ )-, or -NH-(CH ₂ CH ₂ CH ₂ CH ₂ )-. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 16, wherein R ³ is -O-(substituted or unsubstituted C ₁ -C ₆ alkylene)-NH-. The compound of claim 25 or a pharmaceutically acceptable salt thereof, wherein R ³ is -O-(CH ₂ ) ₄ -NH-. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 16, wherein R ³ is -O-(substituted or unsubstituted C ₁ -C ₆ alkylene)-NH-(substituted or unsubstituted C ₁ -C ₆ alkylene)-. The compound of claim 27 or a pharmaceutically acceptable salt thereof, wherein R ³ is -O-(CH ₂ ) ₂ -NH-(CH ₂ )-. The compound of any one of claims 1 to 28 or a pharmaceutically acceptable salt thereof, wherein R ⁴ is absent. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 28, wherein R ⁴ is a substituted or unsubstituted 4- to 10-membered heterocyclic group. The compound of claim 30 or a pharmaceutically acceptable salt thereof, wherein R ⁴ is or . The compound of any one of claims 1 to 31 or a pharmaceutically acceptable salt thereof, wherein R ^C is . The compound of any one of claims 1 to 31 or a pharmaceutically acceptable salt thereof, wherein R ^C is . The compound or pharmaceutically acceptable salt thereof according to any one of claims 1 to 33, wherein R ^D is unsubstituted C ₁ -C ₆ alkyl. The compound or pharmaceutically acceptable salt thereof according to any one of claims 1 to 33, wherein R ^D is substituted C ₁ -C ₆ alkyl. The compound or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 33, wherein R ^D is a halogen-substituted C ₁ -C ₆ alkyl group. The compound of any one of claims 1 to 33 or a pharmaceutically acceptable salt thereof, wherein R ^D is ethyl. The compound of any one of claims 1 to 33 or a pharmaceutically acceptable salt thereof, wherein R ^D is methyl. The compound or pharmaceutically acceptable salt thereof of any one of claims 1 to 33, wherein R ^D is ethyl substituted with a halogen. The compound or pharmaceutically acceptable salt thereof of any one of claims 1 to 33, wherein R ^D is a methyl group substituted with a halogen. The compound of any one of claims 1 to 40 or a pharmaceutically acceptable salt thereof, wherein Y is -CH. The compound of any one of claims 1 to 40 or a pharmaceutically acceptable salt thereof, wherein Y is N. The compound of any one of claims 1 to 42 or a pharmaceutically acceptable salt thereof, wherein at least three of R ¹ , R ² , R ³ , and R ⁴ are present. The compound of any one of claims 1 to 43 or a pharmaceutically acceptable salt thereof, wherein all four of R ¹ , R ² , R ³ , and R ⁴ are present. A compound or a pharmaceutically acceptable salt thereof, wherein the compound has a structure selected from Compound Nos. 1 to 42 listed in Table A or a pharmaceutically acceptable salt thereof. A compound as claimed in any one of claims 1 to 45, wherein one or more hydrogen atoms of the compound are replaced with deuterium. A pharmaceutical composition comprising an effective amount of a compound of any one of claims 1 to 46 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, diluent, excipient, or a combination thereof. Use of an effective amount of a compound as claimed in any one of claims 1 to 46 or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition as claimed in claim 47, in the manufacture of a medicament for improving or treating cancer, wherein the cancer is selected from brain cancer, cervicocerebral cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer, ovarian cancer, choriocarcinoma, corpus uteri cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, cancer), skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Ewing's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma. Use of an effective amount of a compound of any one of claims 1 to 46 or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition of claim 47, in the manufacture of a medicament for inhibiting malignant growth or tumor replication, wherein the malignant growth or tumor is caused by a cancer selected from the following: brain cancer, cranial cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer, Ovarian cancer, choriocarcinoma, corpus uteri cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Evan's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma. Use of an effective amount of a compound of any one of claims 1 to 46 or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition of claim 47, in the manufacture of a medicament for improving or treating malignant growth or tumor, wherein the malignant growth or tumor is caused by a cancer selected from the following: brain cancer, cranial cancer, esophageal cancer, thyroid cancer, small cell carcinoma, non-small cell carcinoma, breast cancer, lung cancer, gastric cancer, gallbladder/bile duct cancer, liver cancer, pancreatic cancer, colon cancer, rectal cancer, Ovarian cancer, choriocarcinoma, corpus uteri cancer, cervical cancer, renal pelvis/ureter cancer, bladder cancer, prostate cancer, penile cancer, testicular cancer, fetal cancer, Wilms' cancer, skin cancer, malignant melanoma, neuroblastoma, osteosarcoma, Evan's tumor, soft tissue sarcoma, acute leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia, polycythemia vera, malignant lymphoma, multiple myeloma, Hodgkin's lymphoma, and non-Hodgkin's lymphoma.

Images