NZ787942A - Nitrile-containing antiviral compounds - Google Patents

Abstract

The invention relates to compounds of Formula I” wherein R, R1, R2, R3, p, q and q’ are as defined herein, pharmaceutical compositions comprising the compounds, methods of treating coronavirus infection such as COVID-19 in a patient by administering therapeutically effective amounts of the compounds, and methods of inhibiting or preventing replication of coronaviruses such as SARS-CoV-2 with the compounds.

Description

e-Containing Antiviral Compounds This application is a divisional of New Zealand patent ation 782196, which is the national phase entry of PCT International application (published as WO/2021/250648), each of which is hereby incorporated by reference herein in its entirety.

Background of the Invention The invention relates to compounds and s of inhibiting viral replication activity comprising contacting a SARS-CoVrelated 3C-like (“3CL”) proteinase with a therapeutically effective amount of a oVrelated 3C-like protease inhibitor.

The invention also relates to s of treating Coronavirus Disease 2019 (“COVID- 19”) in a patient by administering a therapeutically effective amount of a SARS-CoV d 3C-like protease inhibitor to a patient in need thereof. The invention further relates to methods of treating COVID-19 in a patient, the method comprising administering a pharmaceutical composition sing a therapeutically effective amount of the SARS-CoVrelated 3C-like protease inhibitor to a patient in need thereof.

A worldwide outbreak of Coronavirus Disease 2019 (“COVID-19”) has been associated with exposures originating in late 2019 in Wuhan, Hubei Province, China.

By mid-2020 the outbreak of COVID-19 has evolved into a global pandemic with millions of people having been confirmed as infected and resulting in hundreds of thousands of deaths. The ive agent for COVID-19 has been identified as a novel coronavirus which has been named Severe Acute Respiratory Syndrome Corona Virus 2 (“SARS-CoV-2”). The genome sequence of SARS-CoV-2 has been sequenced from isolates obtained from nine patients in Wuhan, China and has been found to be of the subgenus Sarbecovirus of the genus Betacoronavirus. Lu, R. et al. The Lancet, 395, 10224, 565-574; online January 29, 2020. The sequence of SARS-CoV-2 was found to have 88% gy with two bat-derived SARS-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21, which were collected in 2018 in Zhoushan, eastern China.

SARS-CoV-2 was also found to share about 79% homology with Severe Acute Respiratory Syndrome Corona Virus (“SARS-CoV”), the causative agent of the SARS ak in 2002-2003, and about 50% homology with Middle East Respiratory Syndrome Coronavirus (“MERS-CoV”), the causative agent of a respiratory viral ak originating in the Middle East in 2012. Based on a recent analysis of 103 sequenced genomes of SARS-CoV-2 it has been proposed that SARS-CoV-2 can be divided into two major types (L and S types) with the S type being ral and the L type having evolved from the . Lu, J.; Cui, J. et al. On the origin and continuing evolution of SARS-CoV-2; National Science Review, 7(6), June 2020, 1012-1023, http://doi.org/10.1093/nsr/nwaa036. The S and L types can be clearly defined by just two y linked SNPs at positions 8,782 (orf1ab:T8517C, mous) and 28,144 (ORF8: C251T, S84L). In the 103 genomes analyzed approximately 70% were of the L- type and approximately 30% were of the S-type. It is r if the evolution of the L- type from the S-type ed in humans or through a zoonotic intermediate but it appears that the L-type is more aggressive than the S-type and human interference in attempting to n the outbreak may have shifted the relative abundance of the L and S types soon after the SARS-CoV-2 ak began. The discovery of the proposed S- and L- subtypes of SARS-CoV-2 raises the possibility that an individual could potentially be infected sequentially with the individual es or be infected with both subtypes at the same time. In view of this evolving threat there is an acute need in the art for an effective treatment for COVID-19 and for s of inhibiting replication of the SARS-CoV-2 coronavirus.

Recent evidence y shows that the newly emerged coronavirus SARS-CoV- 2, the causative agent of COVID-19 (Centers for Disease Control, CDC) has acquired the ability of human-to-human transmission leading to community spread of the virus.

The sequence of the SARS-CoV-2 spike n receptor-binding domain (“RBD”), including its receptor-binding motif (RBM) that directly contacts the angiotensin- converting enzyme 2 receptor, ACE2, is similar to the RBD and RBM of SARS-CoV, strongly suggesting that SARS-CoV-2 uses ACE2 as its receptor. Wan, Y.; Shang, J.; Graham, R.; Baric, R.S.; Li, F.; Receptor recognition by the novel coronavirus from Wuhan: An analysis based on decade-long structural studies of SARS coronavirus; J.

Virol. 2020; doi:10.1128/JVI.00127-20. Several critical residues in SARS-CoV-2 RBM (particularly Gln493) e favorable interactions with human ACE2, consistent with SARS-CoV-2's capacity for human cell infection. Several other critical residues in SARS-CoV-2’s RBM (particularly ) are compatible with, but not ideal for, binding human ACE2, suggesting that oV-2 uses ACE2 binding in some capacity for human-to-human transmission.

Coronavirus replication and transcription function is encoded by the so-called “replicase” gene (Ziebuhr, J., Snijder, E.J., and Gorbalenya, A.E.; Virus-encoded nases and proteolytic processing in the Nidovirales. J. Gen. Virol. 2000, 81, 853- 879; and Fehr, A.R.; Perlman, S.; Coronaviruses: An Overview of Their Replication and Pathogenesis, Methods Mol. Biol. 2015; 1282: 1–23. .1007/9784939 7_1), which consists of two overlapping polyproteins that are extensively processed by [Link] https://doi.org/10.1101/2020.02.17.952879 viral proteases. The C-proximal region is processed at eleven conserved interdomain junctions by the coronavirus main or “3C-like” se (Ziebuhr, Snijder, Gorbalenya, 2000 and Fehr, Perlman et al., 2015). The name ke” protease derives from certain similarities between the coronavirus enzyme and the nown picornavirus 3C proteases. These include substrate preferences, use of cysteine as an active site nucleophile in sis, and similarities in their putative overall polypeptide folds. The SARS-CoV-2 3CL se sequence (Accession No. YP_009725301.1) has been found to share 96.08% homology when compared with the SARS-CoV 3CL protease sion No. YP_009725301.1) Xu, J.; Zhao, S.; Teng, T.; Abdalla, A.E.; Zhu, W.; Xie, L.; Wang, Y.; Guo, X.; Systematic Comparison of Two Animal-to-Human Transmitted Human Coronaviruses: oV-2 and SARS-CoV; Viruses 2020, 12, 244; doi:10.3390/v12020244. Very ly, Hilgenfeld and colleagues published a high-resolution X-ray ure of the SARS-CoV-2 coronavirus main protease (3CL) Zhang, L.; Lin, D.; Sun, X.; Rox, K.; Hilgenfeld, R.; X-ray Structure of Main Protease of the Novel Coronavirus SARS-CoV-2 s Design of -Ketoamide Inhibitors; bioRxiv preprint doi: https://doi.org/10.1101/2020.02.17.952879. The structure indicat es that there are differences when comparing the 3CL proteases of SARS-CoV-2 and SARSCoV.

In the SARS-CoV but not in the SARS-CoV-2 3CL se dimer, there is a polar interaction between the two domains III involving a 2.60-Å hydrogen bond between the side-chain hydroxyl groups of residue Thr285 of each protomer, and ted by a hydrophobic t n the side-chain of Ile286 and Thr285 C2. In the SARS-CoV-2 3CL, the threonine is replaced by alanine, and the isoleucine by leucine when ed with the same residues in the SARS-CoV 3CL. The Thr285Ala ement observed in the SARS-CoV-2 3CL protease allows the two domains III to approach each other somewhat closer (the distance between the C atoms of residues 285 in molecules A and B is 6.77 Å in SARS-CoV 3CL protease and 5.21 Å in SARSCoV-2 3CL protease and the distance between the centers of mass of the two domains III shrinks from 33.4 Å to 32.1 Å). In the active site of SARS-CoV-2 3CL, Cys145 and His 41 form a catalytic dyad, which when taken together with a with a buried water molecule that is hydrogen-bonded to His41 can be considered to constitute a catalytic triad of the SARS-CoV-2 3CL protease. In view of the ongoing SARS-CoV-2 spread that has caused the current worldwide COVID-19 outbreak, it is desirable to have new methods of inhibiting SARS-CoV-2 viral replication and of treating COVID-19 in patients. It is an object of the present invention to go some way to satisfying one or more of these needs and desires; and/or to at least provide the public with a useful choice.

In this specification where reference has been made to patent specifications, other external documents, or other sources of ation, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, nce to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part of the common general knowledge in the art.

Summary of The Invention In a first aspect, the t invention provides a compound selected from the group consisting of: (2S,4R)tert-Butyl-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{N- [(trifluoromethyl)sulfonyl]-L-valyl}piperidinecarboxamide; (2R,4S)tert-Butyl-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{N- [(trifluoromethyl)sulfonyl]-L-valyl}piperidinecarboxamide; 3-Methyl-N-(trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidin- 3-yl] (trifluoromethyl)-L-prolinamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(methylcarbamoyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; Methyl {(2S)[(1R,2S,5S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl} carbamoyl)-6,6-dimethylazabicyclo[3.1.0]hexanyl]-3,3-dimethyloxobutan- 2-yl}carbamate; N-(Trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}(trifluoromethyl)-L-prolinamide; (1R,2S,5S)-N-{(1S)Cyano[(3R)hydroxyoxopyrrolidinyl]ethyl}-6,6- dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide; ,5S,6R)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl} (hydroxymethyl)methyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S,6S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl} (hydroxymethyl)methyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}[3- (hydroxymethyl)-N-(trifluoroacetyl)-L-valyl]-6,6-dimethylazabicyclo [3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3R)-2,5-dioxopyrrolidinyl]ethyl}-6,6-dimethyl- 3-[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; ,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl [5,5,5-trifluoro(2,2,2-trifluoroacetamido)pentanoyl]azabicyclo[3.1.0]hexane- 2-carboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}[3-cyclobutyl-N- uoroacetyl)-L-alanyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}[3-cyclobutyl-N- (trifluoroacetyl)-D-alanyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- (pyridinyl)-N-(trifluoroacetyl)-L-alanyl]azabicyclo[3.1.0]hexane carboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}{N-[(4- fluorophenoxy)acetyl]methyl-L-valyl}-6,6-dimethylazabicyclo[3.1.0]hexane- 2-carboxamide; 3-Methyl-N-[(4-methylphenyl)acetyl]-L-valyl-(4R)-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}(trifluoromethyl)-L-prolinamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- (1H-pyrazolyl)-N-(trifluoroacetyl)-L-alanyl]azabicyclo[3.1.0]hexane carboxamide; (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}[(2S)-4,4- difluoro(2,2,2-trifluoroacetamido)butanoyl]-6,6-dimethyl azabicyclo[3.1.0]hexanecarboxamide; and (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[2- (2,2,2-trifluoroacetamido)(trifluoromethyl)pentanoyl]azabicyclo[3.1.0] carboxamide; or a solvate or hydrate thereof.

In a second aspect, the present invention provides a pharmaceutical ition comprising a compound of the first aspect or a solvate or hydrate thereof and a pharmaceutically acceptable carrier.

In a third aspect, the present invention provides a method of treating a coronavirus ion in a patient, the method comprising stering a therapeutically effective amount of the compound of the first aspect or a solvate or hydrate thereof, or the pharmaceutical composition of the second aspect to a patient in need thereof, wherein the patient is not a human.

In a fourth aspect, the present ion provides use of the compound of the first aspect or a solvate or hydrate thereof or the ceutical composition of the second aspect in the manufacture of a medicament for ng a coronavirus infection in a patient.

In the description in this specification reference may be made to subject matter which is not within the scope of the claims of the current application. That subject matter should be readily identifiable by a person skilled in the art and may assist in g into practice the invention as defined in the claims of this application.

The term “comprising” as used in this specification and claims means “consisting at least in part of”. When interpreting statements in this specification and claims which e the term “comprising”, other features besides the es prefaced by this term in each statement can also be present. Related terms such as “comprise” and “comprised” are to be interpreted in similar manner.

The present invention provides novel compounds which act in inhibiting or preventing SARS-CoV-2 viral ation and thus are useful in the treatment of COVID- 19. The present invention also provides ceutical compositions comprising the compounds and methods of treating COVID-19 and inhibiting SARS-CoV-2 viral replication by administering the compounds of the invention or pharmaceutical compositions comprising the compounds of the invention. It is to be understood that each of the method of treatment embodiments hereinbelow can also be formulated as ponding use type embodiments. For example, any of the nds, or pharmaceutically acceptable salts, or solvates or hydrates thereof, or pharmaceutically acceptable salts of the compounds, solvates or hydrates as set forth in any of embodiments E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 can be employed for use as a medicament or alternatively for use in a method of treatment as described in any of embodiments E36 to E41, E47 to E49, E52 to E58a, E69 to E74, E77 to R79, E85 to E93 and E95 to E98.

E1 is a compound of E45 or E59, hereinbelow, of Formula I I ; or a pharmaceutically acceptable salt thereof; wherein R1 is selected from the group consisting of C1-C6 alkyl which is optionally substituted with a cyano or with one to five fluoro; C2-C6 alkynyl; and (C3-C6 cycloalkyl)-C1-C3 alkyl which is optionally substituted with one to two substituents selected from oromethyl and C1-C3 alkyl or with one to five fluoro; R2 is hydrogen or R2 and R1 taken together with the nitrogen and carbon atoms to which they are ed are a pyrrolidine or piperidine ring which is optionally tuted with one to four R2a; R2a at each occurrence is independently selected from the group consisting of fluoro, C1-C6 alkyl optionally substituted with one to three fluoro and C1-C6 alkoxy optionally substituted with one to three fluoro; or two R2a groups when attached to adjacent carbons and taken together with the carbons to which they are attached are a fused C3-C6 cycloalkyl which is optionally substituted with one to four R2b; or two R2a groups when attached to the same carbon and taken together with the carbon to which they are attached are a spiro C3-C6 lkyl which is optionally tuted with one to four R2b; R2b at each occurrence is independently selected from fluoro, C1-C3 alkyl optionally tuted with one to three fluoro, and C1-C3 alkoxy ally substituted with one to three fluoro; R3 is selected from the group consisting of C1-C8 alkyl, C1-C8 alkoxy, (C1-C6 alkoxy)-C1-C6 alkyl, C2-C6 alkynyl, C2-C6 alkynyloxy, C3-C12 cycloalkyl optionally fused with a 5- to 6-membered heteroaryl or phenyl, (C3-C12 cycloalkyl)-C1-C6 alkyl, C3-C12 cycloalkoxy, (C3-C12 cycloalkoxy)-C1-C6 alkyl, 4- to 12- membered heterocycloalkyl which is optionally fused with a 5- to 6-membered heteroaryl or phenyl and wherein said heterocycloalkyl comprises one to four heteroatoms ndently selected from N, O and S(O)n, (4- to 12-membered heterocycloalkyl)-C1-C6 alkyl wherein said heterocycloalkyl moiety comprises one to four atoms independently selected from N, O and S(O)n, C6-C10 aryl optionally fused with a C4-C6 cycloalkyl or a 4- to 7-membered heterocycloalkyl, (C6-C10 aryl)-C1- C6 alkyl, 5- to 10-membered aryl comprising one to five heteroatoms independently selected from N, O and S, which is optionally fused with a C5-C6 cycloalkyl; (5- to 10-membered aryl)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five heteroatoms independently selected from N, O and S; (C6-C10 aryl)-(5- to 10-membered heteroaryl)- wherein the heteroaryl moiety comprises one to five atoms independently selected from N, O and S, (5- to 10-membered heteroaryloxy)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five heteroatoms independently selected from N, O and S; (5- to 6-membered heteroaryl)- (5- to 6-membered aryl)- wherein each heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; (4- to 7-membered heterocycloalkyl)-(5- to 6- membered heteroaryl)- wherein the cycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and the heteroaryl moiety ses one to four heteroatoms independently selected from N, O and S; (5- to 6-membered heteroaryl)-(4- to 7-membered heterocycloalkyl)- wherein the heterocycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; wherein each R3 group is optionally substituted with one to five R4; R4 at each occurrence is ndently selected from the group consisting of oxo, halo, y, cyano, , benzyl, amino, (C1-C6 alkyl)amino optionally substituted with one to five fluoro, di(C1-C6 alkyl)amino ally substituted with one to ten fluoro, C1-C6 alkyl optionally substituted with one to five fluoro, C1-C6 alkoxy optionally substituted with one to five , C1-C3 alkoxy-C1- C3 alkyl optionally tuted with one to five fluoro, C3-C6 cycloalkyl optionally substituted with one to three fluoro or C1-C3 alkyl, C1-C6 alkyl-C(O)NH- optionally substituted with one to five fluoro, C1-C6 alkyl-S(O)2NH- optionally substituted with one to five fluoro, C1-C6 alkyl-C(O)- optionally substituted with one to five fluoro, C1-C6 alkyl- S(O)n- optionally substituted with one to five fluoro; and n at each occurrence is independently selected from 0, 1 and 2.

E2 is the compound of any one of E1, E45 and E59 wherein R1 is selected from the group consisting of (CH3)2CHCH2-, (CH3)3CCH2-, cyanomethyl, 2-cyanoethyl, 2,2- difluoroethyl, 2,2,2-trifluoroethyl, 3,3-difluoropropyl, 3,3,3-trifluoropropyl, 3,3,3-trifluoro- 2-methylpropyl, ropylmethyl, (2,2-difluorocyclopropyl)methyl, [1-(trifluoromethyl) cyclopropyl]methyl, hylcyclopropyl)methyl, (3,3-difluorocyclobutyl)methyl, cyclopentylmethyl and propynyl; and R2 is hydrogen; or a pharmaceutically acceptable salt thereof.

E3 is the compound of any one of E1, E45 and E59 wherein R2 and R1 taken together with the nitrogen and carbon atoms to which they are attached are a pyrrolidine or piperidine ring which is ally substituted with one to four R2a; or a pharmaceutically acceptable salt thereof.

E4 is the compound of any one of E1, E45, E59 and E3 wherein R2a at each occurrence is independently selected from the group consisting of fluoro, methyl, pyl, trifluoromethyl and tert-butoxy; or two R2a groups when attached to adjacent s and taken together with the carbons to which they are attached are a fused cyclopentane or cyclopropane which is optionally substituted with one to four R2b; or two R2a groups when attached to the same carbon and taken er with the carbon to which they are ed are a spirocyclopropane ring which is optionally substituted with one to four R2b; or a pharmaceutically acceptable salt thereof.

E5 is the compound of E1, E3, E4, E45 and E59 wherein R2b at each occurrence is independently selected from the group consisting of fluoro, methyl and methoxy; or a pharmaceutically acceptable salt thereof.

E6 is the compound of any one of E1, E2, E45 and E59 selected from the group consisting of formulae Ia through Ig or a pharmaceutically acceptable salt thereof.

E7 is the compound of any one of E1, E3, E4, E45 and E59 ed from the group consisting of formulae Ih through Ik or a pharmaceutically able salt thereof.

E8 is the compound of any one of E1, E3, E4, E7, E45 and E59 selected from the group consisting of or a pharmaceutically able salt thereof.

E9 is the compound of any one of E1, E3, E4, E7, E8, E45 and E59 wherein R3 is selected from the group consisting of C1-C6 alkyl and (C3-C6 cycloalkyl)-C1-C3 alkyl; each of which is substituted with one to four R4; or a pharmaceutically acceptable salt thereof.

E10 is the compound of any one of E1, E3, E4, E7 to E9, E45 and E59 wherein R3 is selected from the group consisting of (CH3)2CHCH(R4)-, (CH3)3CCH(R4)- and (cyclohexyl)CH(R4)-; or a pharmaceutically acceptable salt thereof.

E11 is the nd of any one of E1, E3, E4, E7 to E10, E45 and E59 selected from the group consisting of H3CW0 0 HC3 CH3 N ‘\\\\|J\ H3C CH3 H3C CH3 O N R4 R4 0 H3CW0 O 0 N J\N N CH3 \\\\|J\ H \N Ih—1C F30 EH3 H3O CH3 O N MOW0 o H C3 CH3 ‘\\\\|J\N \ H \N F30 EH3 II-1b 13 13 or a pharmaceutically acceptable salt f.

E12 is the compound of any one of E1, E3, E4, E7 to E11, E45 and E59 wherein R4 is selected from the group consisting of (C1-C6 alkyl)amino optionally tuted with one to five fluoro, C1-C6 alkyl-C(O)NH- optionally substituted with one to five fluoro, and C1-C6 alkyl-S(O)2NH- optionally substituted with one to five fluoro; or a ceutically acceptable salt thereof.

E13 is the compound of any one of E1, E3, E4, E7 to E12, E45 and E59 wherein R4 is selected from the group consisting of CF3C(O)NH-, CF3S(O)2NH-, CH3C(O)NH-, CH3CH2C(O)NH- and CF3CH2NH-; or a pharmaceutically acceptable salt thereof.

E14 is the nd of any one of E1, E3, E4, E7 to E13, E45 and E59 wherein R4 is CF3C(O)NH- or CF3S(O)2NH-; or a pharmaceutically acceptable salt thereof.

E15 is the compound of any one of E1 to E8, E45 and E59 wherein R3 is a 4- to 12-membered heterocycloalkyl which is optionally fused with a 5- to 6-membered heteroaryl or phenyl and wherein said heterocycloalkyl comprises one to four heteroatoms independently selected from N, O and S(O)n, or is a (4- to 12-membered heterocycloalkyl)-C1-C6 alkyl wherein said heterocycloalkyl moiety comprises one to four heteroatoms independently ed from N, O and S(O)n; each of which is optionally tuted with one to five R4; or a pharmaceutically acceptable salt thereof.

E16 is the compound of any one of E1 to E8, E15, E45 and E59 wherein the 4- to 12-membered heterocycloalkyl moiety in R3 is selected from the group consisting of azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, oxetanyl, ydrofuranyl, pyranyl, 2-oxo-1,3-oxazolidinyl, oxabicyclo[2.2.1]heptyl, 1-oxaazaspiro[4.5]decyl, 1,1- dioxido-1,2-thiazolidinyl and 1,1-dioxido-1,2-thiazinanyl; each of which is optionally substituted with one to three R4; or a pharmaceutically acceptable salt f.

E17 is the compound of any one of E1 to E8, E45 and E59 wherein R3 is selected from the group consisting of phenyl, , phenethyl, a 5- to 10-membered heteroaryl comprising one to five heteroatoms independently selected from N, O and S; (5- to 10-membered heteroaryl)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five heteroatoms independently selected from N, O and S; and a (5- to 10- membered heteroaryloxy)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five heteroatoms ndently selected from N, O and S; each of which is optionally substituted with one to five R4; or a pharmaceutically acceptable salt thereof.

E18 is the compound of any one of E1 to E8, E17, E45 and E59 wherein the 5- to 10-membered heteroaryl moiety in R3 is selected from the group consisting of imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, zolyl, triazolyl, nyl, pyrimidinyl, pyrazinyl, pyridazinyl, indolyl, benzimidazolyl, nopyrrolyl, quinolinyl, quinoxalinyl, benzotriazolyl, imidazo[1,2-a]pyridinyl, imidazo[2,1- ]thiazolyl, 4H-furo[3,2-b]pyrrolyl, 4H-thieno[3,2-b]pyrrolyl, [1,2,4]triazolo[1,5- a]pyrimidinyl, [1,2,3]triazolo[1,5-a]pyridinyl and naphthyridinyl; each of which is optionally substituted with one to four R4; or a pharmaceutically acceptable salt thereof.

E19 is the compound of any one of E1 to E8, E17 to E18, E45 and E59 wherein R3 is l; which is optionally substituted with one to four R4; or a pharmaceutically able salt thereof.

E20 is the compound of any one of E1 to E8, E17 to E19, E45 and E59 wherein R3 is indolyl; which is optionally substituted with one to four R4; and R4 at each occurrence is independently selected from the group consisting of fluoro, chloro, bromo, hydroxy, methyl, ethyl, propyl, isopropyl, 1-methylpropyl, butyl, tert-butyl, , methoxy, ethoxy, propoxy, butoxy, trifluoromethyl, trifluoromethoxy, cyclohexyl and diethylamino; or a pharmaceutically able salt thereof.

E21 is the compound of any one of E1, E2, E6, E9 to E10, E12 to E20, E45 and E59 of the formula or a ceutically acceptable salt thereof.

E22 is the compound of any one of E1, E2, E6, E9 to E10, E12 to E21, E45 and E59 wherein R3 is selected from the group consisting of 1H-indolyl, 7-fluoro methoxy-1H-indol-2yl, 4-methoxy(trifluoromethyl)-1H-indolyl, 4-methoxy-1H-indol- 2-yl, 4-(trifluoromethoxy)-1H-indolyl, 6-(trifluoromethyl)-1H-indolyl, 4-methoxy- 3,6,7-tris(trifluoromethyl)-1H-indolyl, 3-fluoromethoxy-1H-indolyl and 3,5- difluoromethoxy-1H-indolyl; or a pharmaceutically acceptable salt thereof.

E23 is the compound of any one of E1 to E8, E21, E45 and E59 wherein R3 is C1-C6 alkoxy; or a pharmaceutically acceptable salt thereof.

E24 is the compound of any one of E1 to E8, E21, E23, E45 and E59 n R3 is selected from the group ting of methoxy, ethoxy and propoxy; or a pharmaceutically acceptable salt thereof.

E25 is the compound of any one of E1 to E8, E21, E45 and E59 wherein R3 is selected from the group consisting of C3-C12 cycloalkyl optionally fused with a 5- to 6- membered aryl or phenyl, (C3-C12 cycloalkyl)-C1-C6 alkyl, C3-C12 cycloalkoxy and (C3-C12 cycloalkoxy)-C1-C6 alkyl; each of which is optionally substituted with one to three R4; or a pharmaceutically able salt thereof.

E26 is the compound of any one of E1 to E8, E21, E25, E45 and E59 wherein R3 is selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 1-(cyclohexyloxy)ethyl, cyclohexoxymethyl, ropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl and cyclohexylethyl; each of which is optionally substituted with one to three R4; or a pharmaceutically acceptable salt thereof.

E27 is the compound of any one of E1 to E8, E17, E45 and E59 wherein R3 is selected from the group consisting of phenyl, benzyl and phenethyl, each of which is optionally substituted with one to three R4; or a pharmaceutically acceptable salt thereof.

E28 is the compound of any one of E1 to E8, E17, E27, E45 and E59 wherein R4 is selected from the group consisting of fluoro, chloro, dimethylamino, trifluoromethyl, )NH- and )2NH-; or a pharmaceutically able salt thereof.

E29 is a compound of any one of E1, E45 and E59 selected from the group consisting of N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{(2R)(dimethylamino)[4- (trifluoromethyl)phenyl]acetyl}methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{(2R)(dimethylamino)[3- (trifluoromethyl)phenyl]acetyl}methyl-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl](trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-3,6,7-tris(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](trifluoromethoxy)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethoxy)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoromethoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-3,5-difluoromethoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-5,7-difluoromethoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoromethoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl tanyl]methoxy-3,5,7-tris(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-3,7-bis(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl](trifluoromethyl)-1H-indolecarboxamide; 7-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxymethyl-1H-indolecarboxamide; 6-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; 4-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; 5-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; 4,6-dichloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; 7-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxymethyl-1H-indolecarboxamide; 6-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; 4-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; 5,7-dichloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino) methyloxopentanyl]-1H-indolecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; 4,6-dichloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino) methyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl]methyl(trifluoromethyl)imidazo[2,1-b][1,3]thiazolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[4-methyl (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[5-methyl (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-leucinamide; N2-[(4-bromoethylmethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-L-leucinamide; N2-[(4-chloro-1,3-dimethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-L-leucinamide; 3-acetyl-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3R)-2,5-dioxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]hydroxy-1H-indolecarboxamide; )({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]hydroxymethoxy-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(3,3-difluorocyclobutyl)acetyl] methyl-L-leucinamide; N2-[(transcyanocyclohexyl)carbonyl]-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}methyl-L-leucinamide; N2-[(transcyanocyclohexyl)carbonyl]-N-{(1R)cyano[(3S)oxopyrrolidin yl}methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[2-(cyclohexyloxy)propanoyl] methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[cyclohexyl(methoxy)acetyl] methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[cyclohexyl(methoxy)acetyl] methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2S)(dimethylamino) phenylacetyl]methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-(pyrrolidinylacetyl)-L- leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2R)(dimethylamino) acetyl]methyl-L-leucinamide; N2-[(4-chloro-1,3-dimethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}methyl-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-3,7-bis(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-3,5-bis(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-3,6-bis(trifluoromethyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(cyclohexylcarbonyl)methyl-L- leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(cyclohexylcarbonyl)methyl-L- leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[2-(trifluoromethyl)-1,3- lyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-[(propanyloxy)acetyl]- L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(cyclohexyloxy)acetyl]methyl- L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-(4,4,4-trifluoro methylbutanoyl)-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methylimidazo[2,1-b][1,3]thiazolecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl- N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-5,5,5-trifluoro oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoromethoxy-1H-indolecarboxamide; )({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-1H-indolecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; -bromoethylmethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}methyl-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(2,6-dichlorobenzoyl)methyl-L- leucinamide; (2S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-4,4-dimethyl[3-methyl-N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; 3-methyl-N-(trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}methyl(trifluoromethyl)-L-prolinamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl{3-methyl-N- [(trifluoromethyl)sulfonyl]-L-valyl}piperidinecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{[2-(trifluoromethyl)-1,3-thiazol yl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2S)(dimethylamino) phenylacetyl]methyl-L-leucinamide; N2-[(transcyanocyclohexyl)carbonyl]-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}methyl-L-leucinamide; N2-[(transcyanocyclohexyl)carbonyl]-N-{(1R)cyano[(3S)oxopyrrolidin yl]ethyl}methyl-L-leucinamide; N-{(1R)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[2-(cyclohexyloxy)propanoyl] methyl-L-leucinamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; -(butanyl)-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(4,5-dichloro-1H-imidazol yl)carbonyl]methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(4,5-dichloro-1H-pyrazol yl)carbonyl]methyl-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl]-2,3-dimethyl-4H-furo[3,2-b]pyrrolecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- yloxopentanyl]-1H-pyrrolo[2,3-b]pyridinecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](trifluoromethyl)-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-1H-pyrrolo[3,2-b]pyridinecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-pyrrolo[3,2-b]pyridinecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]fluoro-1H-benzimidazolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[3-(propanyl)-1H- pyrazolyl]carbonyl}-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]fluoro-1H-benzimidazolecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-5,6-difluoro-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-4H-thieno[3,2-b]pyrrolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[3-(2-methylpropyl)-1H- pyrazolyl]carbonyl}-L-leucinamide; N2-{[4-(3-chlorophenyl)-1H-imidazolyl]carbonyl}-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}methyl-L-leucinamide; N2-[(3-tert-butyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}methyl-L-leucinamide; 6-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl]methyl-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-4,5,6,7-tetrahydro-1H-indazolecarboxamide; 4,6-dichloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-benzimidazolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl](1-methylcyclopropyl)(trifluoromethyl)-1H-pyrrolo[2,3-b]pyridine carboxamide; N2-{[5-(2-chlorophenyl)fluoro-1H-pyrazolyl]carbonyl}-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}methyl-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methyl-4H-thieno[3,2-b]pyrrolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{[3-(4-methoxyphenyl)-1H- pyrazolyl]carbonyl}methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{[3-(2-methoxyphenyl)-1H- pyrazolyl]carbonyl}methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{[4-(4-methoxyphenyl)-1H- imidazolyl]carbonyl}methyl-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[3-(4-methylphenyl)- 1H-pyrazolyl]carbonyl}-L-leucinamide; o-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- yloxopentanyl]methyl-1H-indolecarboxamide; 7-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[3-methyl-N- (methylsulfonyl)-L-valyl]piperidinecarboxamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[3-methyl-N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[3-methyl-N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; 5-[(2S)-butanyl]-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- 4,4-dimethyloxopentanyl]-1H-indolecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3',3',3'- trifluoro-N-(trifluoroacetyl)-L-isoleucyl]azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{(2S)cyclohexyl luoroacetyl)amino]acetyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{(2S)cyclopentyl [(trifluoroacetyl)amino]acetyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[4-methyl- N-(trifluoroacetyl)-L-leucyl]azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{(2S)(4,4- difluorocyclohexyl)[(trifluoroacetyl)amino]acetyl}-6,6-dimethyl azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[3-cyclopentyl-N- (trifluoroacetyl)-L-alanyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[3-cyclohexyl-N- uoroacetyl)-L-alanyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-leucyl]azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[6,6-difluoro-N- (trifluoroacetyl)-L-norleucyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl{(2S)- 4,4,4-trifluoro[(trifluoroacetyl)amino]butanoyl}azabicyclo[3.1.0]hexane carboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[3-fluoro-N- (trifluoroacetyl)-L-valyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{(2S)cyclopropyl [(trifluoroacetyl)amino]acetyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[3-(3,3- difluorocyclobutyl)-N-(trifluoroacetyl)-L-alanyl]-6,6-dimethylazabicyclo[3.1.0]hexane- 2-carboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-O-(trifluoromethyl)-L-seryl]azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl{(2S) phenyl[(trifluoroacetyl)amino]acetyl}azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-phenylalanyl]azabicyclo[3.1.0]hexanecarboxamide; ,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}[3,5-difluoro-N- (trifluoroacetyl)-L-phenylalanyl]-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)(trifluoromethyl)-L-phenylalanyl]azabicyclo[3.1.0]hexane carboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N-(2,2,2- trifluoroethyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl{(2S)methyl- 2-[(trifluoroacetyl)amino]butyl}piperidinecarboxamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl{(2S)methyl- 2-[(2,2,2-trifluoroethyl)amino]butyl}piperidinecarboxamide; ,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N-(3,3,3- trifluoropropanoyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl(N- propanoyl-L-valyl)azabicyclo[3.1.0]hexanecarboxamide; (2S,4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[N-(2,2,2- trifluoroethyl)-L-valyl]piperidinecarboxamide; N2-[(4-chloroethylmethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-L-leucinamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]ethyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]cyclohexyl-1H-indolecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-3,5-dimethyl-1H-indolecarboxamide; -tert-butyl-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl- 1-oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](propanyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]ethyl-1H-indolecarboxamide; )({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl tanyl]ethyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]ethyl-1H-indolecarboxamide; 4-butoxy-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](trifluoromethoxy)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl](diethylamino)-1H-indolecarboxamide; 4-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; -bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; 6-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]propoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]-4,5-dimethoxy-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-[(4-methyl-1,3-thiazol bonyl]-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(ethoxycarbonyl)-L-leucinamide; )cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(ethoxycarbonyl)methyl-L- leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-5,5,5-trifluoro oxopentanyl]methoxy-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[2-(trifluoromethyl)-1,3- oxazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[3-(trifluoromethyl)-1,2- thiazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[3-(trifluoromethyl)-1,2- oxazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-{[2-(trifluoromethyl)-1,3-thiazol yl]carbonyl}-L-leucinamide; )cyano[(3S)oxopyrrolidinyl]ethyl}-5,5,5-trifluoro-N2-{[2- (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-norvalinamide; (4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-5,5,5-trifluoro-N2-{[2- (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-leucinamide; (4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-5,5,5-trifluoro-N2-{[2- (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)cyclopentyl oxopropanyl](trifluoromethyl)-1,3-thiazolecarboxamide; )cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[5-(trifluoromethyl)-1,2- thiazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[5-(trifluoromethyl)-1,2- oxazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[2-(trifluoromethyl)-1,3- oxazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[2-(trifluoromethyl)-1,3- thiazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-5,5,5-trifluoromethyl-N2-{[2- (trifluoromethyl)-1,3-thiazolyl]carbonyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-{[(2S) methyltetrahydrofuranyl]carbonyl}-L-leucinamide; N-[(2S,4R)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-5,5,5-trifluoro methyloxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S,4S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-5,5,5-trifluoro methyloxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-5,5,5-trifluoro-4,4- dimethyloxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)cyclopentyl oxopropanyl]methoxy-1H-indolecarboxamide; ,7-dichloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; 5-chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]ethyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]cyclohexyl-1H-indolecarboxamide; -chloro-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-3,5-dimethyl-1H-indolecarboxamide; -butyl-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](propanyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](propanyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]ethyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]ethyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]ethyl-1H-indolecarboxamide; xy-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl](trifluoromethoxy)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl](diethylamino)-1H-indolecarboxamide; 4-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; 5-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; 6-bromo-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]propoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]fluoro-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl tanyl]methoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]-4,5-dimethoxy-1H-indolecarboxamide; -(butanyl)-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino) methyloxopentanyl]-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl tanyl](propanyl)-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methyl-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide; -(butanyl)-N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]-1H-indolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2R)cyclohexyl methoxyacetyl]-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2R) (cyclohexyloxy)propanoyl]-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-(4,4,4-trifluoro methylbutanoyl)-L-leucinamide; N2-[(transcyanocyclohexyl)carbonyl]-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(1-ethylmethyl-1H-pyrazol yl)carbonyl]-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(cyclohexylcarbonyl)-L- leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(cyclohexyloxy)acetyl]-L- leucinamide; )cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(3,3-difluorocyclobutyl)acetyl]-L- leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(propanyloxy)acetyl]-L- leucinamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methylimidazo[2,1-b][1,3]thiazolecarboxamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(2R)cyclohexyl methoxyacetyl]methyl-L-leucinamide; )cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(1-ethylmethyl-1H-pyrazol yl)carbonyl]methyl-L-leucinamide; N2-[2-chloro(methylsulfonyl)benzoyl]-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}-L-leucinamide; N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(2,6-dichlorobenzoyl)-L- leucinamide; (1R,2S,5S)[N-(tert-butylsulfonyl)methyl-L-valyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S){[(3R)benzyloxopyrrolidinyl]carbonyl}-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl{[(3R) oxophenylpyrrolidinyl]carbonyl}azabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S){[(3R)tert-butyloxopyrrolidinyl]carbonyl}-N-{(1S)cyano[(3S)- 2-oxopyrrolidinyl]ethyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[(3- methylimidazo[2,1-b][1,3]thiazolyl)carbonyl]azabicyclo[3.1.0]hexane carboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl{[2- (trifluoromethyl)-1,3-thiazolyl]carbonyl}azabicyclo[3.1.0]hexanecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)cyclopropyl panyl]methoxy-1H-indolecarboxamide; and N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)cyclopropyl oxopropanyl]-1H-indolecarboxamide; or a pharmaceutically acceptable salt f.

E30 is a compound of any one of E1, E45 and E59 selected from the group consisting of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]fluoromethoxy-1H-indolecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; ,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl- N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]fluoromethoxy-1H-indolecarboxamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl[3-methyl-N- (trifluoroacetyl)-L-valyl]piperidinecarboxamide; (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{(2S)cyclohexyl [(trifluoroacetyl)amino]acetyl}-6,6-dimethylazabicyclo[3.1.0]hexanecarboxamide; (2S,4S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl{3-methyl-N- [(trifluoromethyl)sulfonyl]-L-valyl}piperidinecarboxamide; 3-methyl-N-(trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidin yl}methyl(trifluoromethyl)-L-prolinamide; and (2S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-4,4-dimethyl[3-methyl-N- uoroacetyl)-L-valyl]piperidinecarboxamide; or a pharmaceutically acceptable salt thereof.

E31 is a pharmaceutical composition comprising a therapeutically ive amount of a compound of any one of E1 to E30 or a pharmaceutically acceptable salt thereof, together with a pharmaceutically acceptable carrier.

E32 is the pharmaceutical composition of E31 wherein the composition is in the form of an intravenous, subcutaneous, inhaled or oral dosage form.

E33 is the pharmaceutical composition of E31 or E32 wherein the composition is in an oral dosage form.

E34 is the ceutical composition of any one of E31 to E33 further comprising an additional therapeutic agent.

E35 is the pharmaceutical composition of any one of E31 to E34 wherein the pharmaceutical ition further comprises one or more of dexamethasone, azithromycin, and remdesivir.

E36 is a method of treating a coronavirus infection in a patient, the method comprising administering a therapeutically effective amount of a compound of any one of E1 to E30 or a ceutically able salt thereof to a patient in need thereof.

E37 is the method of E36 wherein the coronavirus infection is COVID-19.

E38 is a method of treating a coronavirus infection in a patient, the method comprising administering a pharmaceutical composition of any one of E31 to E35 to a patient in need f.

E39 is the method of E38 wherein the coronavirus infection is 19.

E40 is a method of inhibiting or preventing SARS-CoV-2 viral replication comprising contacting the SARS-CoV-2 coronavirus 3CL protease with a therapeutically effective amount of a compound or a pharmaceutically acceptable salt thereof of any one of E1 to E30.

E41 is a method of ting or preventing SARS-CoV-2 viral ation in a patient sing administering to the patient in need of inhibition of or prevention of SARS-CoV-2 viral replication a therapeutically effective amount of a compound or a pharmaceutically acceptable salt thereof of any one of E1 to E30.

E42 is the use of a compound or a pharmaceutically acceptable salt thereof of any one of E1 to E30 for the treatment of a coronavirus infection.

E43 is the use of E42 wherein the coronavirus infection is COVID-19.

E44 is the use of a compound or a pharmaceutically acceptable salt thereof of any one of E1 to E30 for the preparation of a medicament that is useful for the treatment of a coronavirus infection.

E44a is the use of E44 wherein the coronavirus infection is COVID-19.

E45 is a compound of Formula I’ I’ ; or a pharmaceutically acceptable salt thereof; wherein R at each occurrence is independently hydroxy or oxo; p is 0, 1 or 2; R1 is selected from the group consisting of C1-C6 alkyl which is optionally substituted with a cyano or with one to five fluoro; C2-C6 l; and (C3-C6 lkyl)-C1-C3 alkyl which is optionally substituted with one to two substituents ed from trifluoromethyl and C1-C3 alkyl or with one to five fluoro; R2 is hydrogen or R2 and R1 taken together with the nitrogen and carbon atoms to which they are attached are a pyrrolidine or piperidine ring which is optionally substituted with one to four R2a; R2a at each occurrence is independently selected from the group consisting of fluoro, hydroxy, C1-C6 alkyl optionally substituted with one to three fluoro and C1-C6 alkoxy optionally substituted with one to three fluoro; or two R2a groups when attached to adjacent carbons and taken together with the carbons to which they are attached are a fused C3-C6 cycloalkyl which is optionally substituted with one to four R2b; or two R2a groups when attached to the same carbon and taken together with the carbon to which they are attached are a spiro C3-C6 cycloalkyl which is optionally substituted with one to four R2b; R2b at each occurrence is independently selected from fluoro, hydroxy, C1-C3 alkyl optionally independently tuted with one to three fluoro or hydroxy and C1-C3 alkoxy optionally independently substituted with one to three fluoro or hydroxy; R3 is selected from the group consisting of C1-C8 alkyl, C1-C8 alkoxy, (C1-C6 alkoxy)-C1-C6 alkyl, C2-C6 alkynyl, C2-C6 loxy, C3-C12 cycloalkyl optionally fused with a 5- to 6- membered heteroaryl or phenyl, (C3-C12 lkyl)-C1-C6 alkyl, C3-C12 cycloalkoxy, (C3- C12 lkoxy)-C1-C6 alkyl, 4- to 12-membered heterocycloalkyl which is optionally fused with a 5- to 6-membered heteroaryl or phenyl and wherein said heterocycloalkyl comprises one to four heteroatoms independently selected from N, O and S(O)n, (4- to 12-membered heterocycloalkyl)-C1-C6 alkyl wherein said heterocycloalkyl moiety comprises one to four heteroatoms independently selected from N, O and S(O)n, C6-C10 aryl optionally fused with a C4-C6 cycloalkyl or a 4- to 7-membered heterocycloalkyl, (C6-C10 aryl)-C1-C6 alkyl, 5- to 10-membered heteroaryl comprising one to five heteroatoms independently selected from N, O and S, which is optionally fused with a C5-C6 cycloalkyl; (5- to 10-membered heteroaryl)-C1-C6 alkyl wherein the heteroaryl moiety ses one to five heteroatoms independently selected from N, O and S; (C6- C10 aryl)-(5- to 10-membered heteroaryl)- wherein the heteroaryl moiety comprises one to five heteroatoms independently selected from N, O and S, (5- to 10-membered heteroaryloxy)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five atoms independently selected from N, O and S; (5- to 6-membered heteroaryl)- (5- to 6-membered heteroaryl)- n each heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; (4- to 7-membered heterocycloalkyl)-(5- to 6-membered heteroaryl)- n the heterocycloalkyl moiety ses one to three atoms ndently selected from N, O and S(O)n and the aryl moiety comprises one to four heteroatoms independently selected from N, O and S; (5- to 6-membered heteroaryl)-(4- to 7-membered heterocycloalkyl)- wherein the cycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and the heteroaryl moiety ses one to four heteroatoms independently selected from N, O and S; wherein each R3 group is optionally substituted with one to five R4; R4 at each occurrence is independently selected from the group consisting of oxo, halo, hydroxy, cyano, phenyl, benzyl, amino, (C1-C6 alkyl)amino optionally substituted with one to five fluoro, di(C1-C6 alkyl)amino optionally tuted with one to ten fluoro, C1-C6 alkyl optionally substituted with one to five fluoro, C1-C6 alkoxy optionally substituted with one to five fluoro, C1-C3 alkoxy-C1- C3 alkyl optionally substituted with one to five fluoro, C3-C6 lkyl optionally substituted with one to three fluoro or C1-C3 alkyl, C1-C6 alkyl-C(O)NH- optionally substituted with one to five fluoro, C1-C6 OC(O)NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-NHC(O)NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-S(O)2NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-C(O)- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-S(O)n- optionally substituted with one to five fluoro or with one R5; R5 is selected from phenyl, phenoxy, C3-C6 cycloalkyl, C3-C6 lkoxy, 4- to 7- ed heterocycloalkyl- wherein the cycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and 5- to 6-membered heteroaryl- wherein the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; wherein each R5 is optionally independently substituted with one to three halo, C1-C3 alkyl and C1-C3 alkoxy; and n at each occurrence is independently selected from 0, 1 and 2.

E46 is a compound of selected from the group consisting of (2S,4R)tert-butyl- N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}{N-[(trifluoromethyl)sulfonyl]-L- valyl}piperidinecarboxamide; (2R,4S)tert-butyl-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}{N-[(trifluoromethyl)sulfonyl]-L-valyl}piperidine carboxamide; yl-N-(trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}(trifluoromethyl)-L-prolinamide; (1R,2S,5S)-N-{(1S)cyano- 2-[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(methylcarbamoyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide; methyl {(2S)[(1R,2S,5S)({(1S) cyano[(3S)oxopyrrolidinyl]ethyl}carbamoyl)-6,6-dimethyl azabicyclo[3.1.0]hexanyl]-3,3-dimethyloxobutanyl}carbamate; and N- (trifluoroacetyl)-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl} (trifluoromethyl)-L-prolinamide; or a ceutically able salt thereof.

E47 is a method of treating a coronavirus infection in a patient, the method comprising administering a therapeutically effective amount of a compound of any one of E45 and E46 or a pharmaceutically able salt thereof to a patient in need thereof.

E48 is the method of E47 n the coronavirus infection is 19.

E49 is a method of treating a coronavirus infection in a patient, the method comprising stering a therapeutically effective amount of a compound of any one of E1 to E30 and E45 to E46 or a pharmaceutically acceptable salt thereof n an additional therapeutic agent is administered and the additional therapeutic agent is selected from the group ting of remdesivir, galidesivir, favilavir/avifavir, molnupiravir, AT-527, AT-301, BLD-2660, favipiravir, camostat, SLV213, emtrictabine/tenofivir, ine, dalcetrapib, boceprevir, ABX464, thasone, hydrocortisone, convalescent plasma, gelsolin (Rhu-p65N), regdanvimab (Regkirova), ravulizumab (Ultomiris), VIR-7831/VIR-7832, BRII-196/BRII-198, COVI-AMG/COVI DROPS (STI-2020), bamlanivimab V555), mavrilimab, leronlimab (PRO140), AZD7442, lenzilumab, infliximab, adalimumab, JS 016, STI-1499 (COVIGUARD), lanadelumab (Takhzyro), canakinumab (Ilaris), gimsilumab, ab, casirivimab/imdevimab (REGN-Cov2), MK-7110 (CD24Fc/SACCOVID), heparin, apixaban, tocilizumab (Actemra), sarilumab (Kevzara), apilimod dimesylate, DNL758, DC402234, PB1046, dapaglifozin, abivertinib, ATR-002, tinib, acalabrutinib, baricitinib, tofacitinib, losmapimod, famotidine, vir, niclosamide and diminazene.

E50 is the compound (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidin yl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane- 2-carboxamide; or a pharmaceutically acceptable salt thereof.

E50a is the compound (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidin yl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane- 2-carboxamide.

E51 is a pharmaceutical composition comprising a therapeutically effective amount of (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl- 3-[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable carrier.

E51a is a pharmaceutical composition sing a therapeutically effective amount of (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl- 3-[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide together with a pharmaceutically acceptable carrier.

E52 is a method of treating a coronavirus ion in a patient, the method comprising administering a therapeutically effective amount of ,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof to a patient in need of treatment thereof.

E52a is a method of treating a coronavirus infection in a patient, the method comprising administering a therapeutically effective amount of (1R,2S,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide to a patient in need of treatment thereof.

E53 is the method of E52 wherein the coronavirus infection is COVID-19.

E53a is the method of E52a wherein the coronavirus infection is COVID-19.

E54 is the method of E52 or E53 wherein ,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof is administered .

E54a is the method of E52a or E53a wherein ,5S)-N-{(1S)Cyano [(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide is administered .

E55 is the method of E54 wherein 50 mg to 1500 mg of (1R,2S,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof is administered each day.

E55a is the method of E54a wherein 50 mg to 1500 mg of (1R,2S,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide is administered each day.

E56 is the method of E55 wherein 380 mg of (1R,2S,5S)-N-{(1S)Cyano [(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] yclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof is administered three times a day.

E56a is the method of E55a wherein 380 mg of (1R,2S,5S)-N-{(1S)Cyano [(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide; or a ceutically acceptable salt thereof is administered three times a day.

E57 is the method of E55 wherein 50 mg to 1500 mg of (1R,2S,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof is administered each day as an oral suspension, e or tablet.

E57a is the method of E55a wherein 50 mg to 1500 mg of (1R,2S,5S)-N-{(1S) Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide; or a pharmaceutically acceptable salt thereof is administered each day as an oral suspension, capsule or tablet.

E58 is the method of E57 wherein a tablet is administered.

E58a is the method of E57a wherein a tablet is administered.

E59 is a compound of a I” I” ; or a solvate or e thereof, or a pharmaceutically acceptable salt of said compound, solvate or hydrate thereof; wherein R at each occurrence is independently hydroxy or oxo; q and q’ are each independently selected from 0, 1 and 2; p is 0, 1 or 2; R1 is selected from the group consisting of C1-C6 alkyl which is optionally substituted with a cyano or with one to five fluoro; C2-C6 alkynyl; and (C3-C6 cycloalkyl)-C1-C3 alkyl which is optionally substituted with one to two substituents selected from trifluoromethyl and C1-C3 alkyl or with one to five fluoro; R2 is hydrogen or R2 and R1 taken er with the nitrogen and carbon atoms to which they are attached are a idine or piperidine ring which is optionally substituted with one to four R2a; R2a at each occurrence is independently selected from the group consisting of fluoro, hydroxy, C1-C6 alkyl optionally substituted with one to three fluoro and C1-C6 alkoxy optionally tuted with one to three fluoro; or two R2a groups when attached to adjacent carbons and taken together with the carbons to which they are attached are a fused C3-C6 cycloalkyl which is optionally substituted with one to four R2b; or two R2a groups when attached to the same carbon and taken together with the carbon to which they are attached are a spiro C3-C6 cycloalkyl which is optionally substituted with one to four R2b; R2b at each occurrence is independently selected from , y, C1-C3 alkyl optionally independently substituted with one to three fluoro or hydroxy and C1-C3 alkoxy optionally ndently substituted with one to three fluoro or hydroxy; R3 is selected from the group consisting of C1-C8 alkyl, C1-C8 alkoxy, (C1-C6 alkoxy)-C1- C6 alkyl, C2-C6 alkynyl, C2-C6 alkynyloxy, C3-C12 cycloalkyl optionally fused with a 5- to 6-membered heteroaryl or phenyl, (C3-C12 cycloalkyl)-C1-C6 alkyl, C3-C12 cycloalkoxy, (C3-C12 cycloalkoxy)-C1-C6 alkyl, 4- to 12-membered heterocycloalkyl which is optionally fused with a 5- to 6-membered heteroaryl or phenyl and wherein said heterocycloalkyl comprises one to four heteroatoms independently selected from N, O and S(O)n, (4- to 12-membered heterocycloalkyl)-C1-C6 alkyl wherein said heterocycloalkyl moiety comprises one to four heteroatoms independently selected from N, O and S(O)n, C6-C10 aryl optionally fused with a C4-C6 cycloalkyl or a 4- to 7-membered heterocycloalkyl, (C6-C10 C1-C6 alkyl, 5- to bered heteroaryl comprising one to five atoms independently selected from N, O and S, which is optionally fused with a C5-C6 cycloalkyl; (5- to 10-membered heteroaryl)-C1-C6 alkyl wherein the aryl moiety comprises one to five heteroatoms independently selected from N, O and S; (C6- C10 aryl)-(5- to bered heteroaryl)- n the heteroaryl moiety comprises one to five heteroatoms ndently selected from N, O and S, (5- to 10-membered heteroaryloxy)-C1-C6 alkyl wherein the heteroaryl moiety comprises one to five atoms independently selected from N, O and S; (5- to 6-membered heteroaryl)- (5- to 6-membered heteroaryl)- wherein each heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; (4- to 7-membered cycloalkyl)-(5- to ered heteroaryl)- wherein the heterocycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; (5- to 6-membered heteroaryl)-(4- to 7-membered cycloalkyl)- wherein the heterocycloalkyl moiety ses one to three heteroatoms independently ed from N, O and S(O)n and the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; wherein each R3 group is ally substituted with one to five R4; R4 at each occurrence is ndently selected from the group consisting of oxo, halo, hydroxy, cyano, phenyl, benzyl, amino, (C1-C6 alkyl)amino optionally substituted with one to five fluoro, C6 alkyl)amino optionally substituted with one to ten fluoro, C1- C6 alkyl optionally substituted with one to five fluoro, (5- to 6-membered heteroaryl)amino- wherein the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; (4- to 7-membered heterocycloalkyl)amino- wherein the heterocycloalkyl moiety ses one to three heteroatoms independently selected from N, O and S(O)n, C1-C6 alkoxy optionally tuted with one to five fluoro, C1-C3 alkoxy-C1-C3 alkyl optionally substituted with one to five fluoro, C3-C6 cycloalkyl optionally substituted with one to three fluoro or C1-C3 alkyl, C1-C6 alkyl-C(O)NH- optionally substituted with one to five fluoro, C1-C6 alkyl-OC(O)NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-NHC(O)NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-S(O)2NH- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-C(O)- optionally substituted with one to five fluoro or with one R5, C1-C6 alkyl-S(O)n- optionally substituted with one to five fluoro or with one R5; R5 is selected from phenyl, phenoxy, C3-C6 cycloalkyl, C3-C6 cycloalkoxy, 4- to 7- membered heterocycloalkyl- wherein the heterocycloalkyl moiety comprises one to three heteroatoms independently selected from N, O and S(O)n and 5- to 6-membered heteroaryl- wherein the heteroaryl moiety comprises one to four heteroatoms independently selected from N, O and S; n each R5 is optionally independently substituted with one to three halo, C1-C3 alkyl and C1-C3 alkoxy; and n at each occurrence is independently selected from 0, 1 and 2.

E60 is the compound of E59 which is (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide; or a solvate or hydrate thereof, or a pharmaceutically acceptable salt of said compound, solvate or hydrate.

E61 is the compound (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}- 6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide having the ure or a solvate or hydrate thereof.

E62 is the compound of E61 which is crystalline (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] yclo[3.1.0]hexanecarboxamide.

E63 is the compound of E62 which is lline (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, Solid Form 1.

E64 is the nd of E62 which is crystalline (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, Solid Form 4.

E65 is the compound of E61 which is amorphous (1R,2S,5S)-N-{(1S)Cyano[(3S)- 2-oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide.

E66 is the compound of E61 which is (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl solvate.

E67 is the compound of E66 which is crystalline (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl e.

E68 is the compound of E67 which is lline (1R,2S,5S)-N-{(1S)Cyano[(3S) oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl solvate, Solid Form 2.

E69 is a method of treating a coronavirus infection in a patient, the method comprising administering a therapeutically effective amount of a compound according to any one of E61 to E68 to a patient in need of treatment thereof.

E70 is the method of E69 wherein the coronavirus infection is COVID-19.

E71 is the method of E70 wherein ritonavir is also stered to the patient.

E72 is the method of E71 n the compound of any one of E61 to E68 and vir are administered to the t orally.

E73 is the method of E72 wherein about 10 mg to about 1500 mg per day of the compound of any one of E61 to E68 and about 10 mg to about 1000 mg per day of ritonavir are administered.

E74 is the method of E73 wherein about 50 mg of the compound of any one of E61 to E68 and about 100 mg of ritonavir are each administered to the patient twice a day.

E75 is a pharmaceutical composition comprising a therapeutically effective amount of ,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; or a solvate or hydrate f, or a pharmaceutically acceptable salt of said compound, solvate or hydrate together with a pharmaceutically acceptable carrier.

E75a is a pharmaceutical composition comprising a therapeutically effective amount of (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide; or a solvate or hydrate thereof together with a pharmaceutically acceptable carrier.

E76 is the pharmaceutical composition of E75a comprising the compound ing to any one of E62 to E68.

E77 is the method of E69 or E70 wherein about 100 mg, 150 mg, 200 mg, 250 mg, 300 mg, 350 mg, 400 mg, 450 mg, 500 mg, 550 mg, 600 mg, 650 mg, 700 mg or 750 mg of the compound according to any one of E61 to E68 is administered orally to the patient twice a day.

E78 is the method of E77 wherein ritonavir is co-administered orally to the patient twice a day.

E79 is the method of E78 wherein about 300 mg of the compound according to any one of E61 to E68 and about 100 mg of vir are co-administered to the patient twice a E80 is the compound of E63 which is characterized by a 19F peak with a chemical shift at -73.3 ± 0.1 ppm and 13C peaks with al shifts at 31.0 ± 0.1 ppm, 27.9 ± 0.1 ppm and 178.9 ± 0.2 ppm.

E81 is the compound of E64 which is characterized by one or more peaks selected from the group consisting of a 19F peak with chemical shift at -73.6 ± 0.1 ppm and 13C peaks at 26.9 ± 0.1 ppm, 21.6 ± 0.1 ppm and 41.5 ± 0.1 ppm.

E82 is the compound hoxycarbonyl)methyl-L-valyl-(4R)-N-{(1S)cyano [(3S)oxopyrrolidinyl]ethyl}(trifluoromethyl)-L-prolinamide having the structure ; or a solvate or hydrate thereof.

E83 is the compound of E82 which is N-(Methoxycarbonyl)methyl-L-valyl-(4R)-N- {(1S)cyano[(3S)oxopyrrolidinyl]ethyl}(trifluoromethyl)-L-prolinamide.

E84 is a pharmaceutical comprising a therapeutically effective amount of N- (Methoxycarbonyl)methyl-L-valyl-(4R)-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}(trifluoromethyl)-L-prolinamide; or a solvate or e thereof together with a pharmaceutically acceptable carrier.

E85 is a method of treating a virus infection in a patient, the method comprising administering a therapeutically effective amount of a compound of E82 or E83 to a t in need of treatment thereof.

E86 is the method of E85 wherein the virus infection is COVID-19.

E87 is the method of E85 or E86 wherein 10 mg to 1500 mg per day of the compound of E82 or E83 is administered.

E88 is the method of any one of E85 to E87 wherein the compound is administered orally.

E89 is the method of E88 wherein 200 mg of the compound is administered twice a E90 is a method of ing SARS-CoV-2 inhibition a compound of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 as a means of treating indications caused by SARS-CoVrelated viral infections.

E91 is a method of identifying cellular or viral pathways interfering with the functioning of the members of which could be used for treating indications caused by SARS-CoV-2 infections by administering a SARS-CoV-2 protease inhibitor compound of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83.

E92 is a method of using a oV-2 protease inhibitor compound of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 as tools for understanding mechanism of action of other SARS-CoV-2 inhibitors.

E93 is a method of using a SARS-CoV-2 3C-like protease inhibitor compound of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 for carrying out gene-profiling experiments for monitoring the up- or down-regulation of genes for the purpose of identifying inhibitors for ng tions caused by SARS-CoV-2 infections such as COVID-19.

E94 is a pharmaceutical composition for the treatment of COVID-19 in a mammal containing an amount of a SARS-CoV-2 e protease inhibitor compound of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 that is effective in treating COVID-19 together with a pharmaceutically acceptable carrier.

E95 is a method of treating MERS in a patient, the method comprising administering a therapeutically effective amount of a nd of any one of E1 to E30, E45 to E46, E50, E50a, E59 to E68 and E80 to E83 to a patient in need thereof.

E96 is a method of treating MERS in a patient, the method comprising administering a pharmaceutical composition of any one of E31 to E35, E51, E51a, E75, E75a, E84 and E94 to a patient in need thereof.

E97 is a method of inhibiting or ting MERS viral replication comprising contacting the SARS-CoV-2 coronavirus 3CL protease with a therapeutically effective amount of a compound of any one of E1 to E30, 45-46, 50, 50a, 59-68 and 80-83.

E98 is a method of inhibiting or ting MERS viral replication in a patient comprising administering to the patient in need of inhibition of or prevention of MERS viral replication a therapeutically effective amount of a compound of any one of E1 to E30, 45-46, 50, 50a, 59-68 and 80-83.

E99 Use of a compound of any one of E1 to E30, 45-46, 50, 50a, 59-68 and 80-83 for the ent of a coronavirus ion.

E100 The use of E99 wherein the coronavirus infection is COVID-19.

E101 Use of a nd of any one of E1 to E30, 45-46, 50, 50a, 59-68 and 80-83 in the preparation of a medicament.

E102 is a compound of any one of embodiments E1 to E30, or a pharmaceutically acceptable salt thereof, for use as a medicament.

E103 is a compound of any one of ments E1 to E30, or a pharmaceutically acceptable salt thereof, for use in a method of treatment, wherein the method is as described in any one of embodiments E36 to E41.

Brief Description of the Drawings Figure 1: Powder X-ray ction Pattern of 13, methyl tert-butyl ether solvate, Solid Form 2, from Alternate Synthesis of Example 13, methyl tert-butyl ether solvate; Generation of Solid Form 2 Figure 2: Powder X-ray Diffraction n of 13, methyl tert-butyl ether solvate, Solid Form 2, from Second Alternate Synthesis of Example 13, methyl tert-butyl ether solvate; Generation of Solid Form 2 Figure 3: Powder X-ray Diffraction n of Example 13, Solid Form 1, from Recrystallization of Example 13; Generation of Solid Form 1 Figure 4: -crystal X-ray Structural Determination of Example 13, Solid Form 1.

ORTEP diagram drawn with displacement parameters at 50% probability Figure 5: Overlay of powder pattern obtained for Example 13, Solid Form 1, from Recrystallization of Example 13; Generation of Solid Form 1 (Figure 3) and the calculated powder pattern, generated via y software, from ed X-ray singlecrystal data of Form 1 (see Single-crystal X-ray Structural Determination of Example 13, Solid Form 1).

Figure 6: Powder X-ray Diffraction Pattern of Example 13, Solid Form 4, from Alternate Recrystallization of e 13; Generation of Solid Form 4 Figure 7: Single-crystal X-ray Structural Determination of Example 13, Solid Form 4.

ORTEP diagram drawn with displacement parameters at 50% probability Figure 8: Overlay of powder pattern obtained for Example 13, Solid Form 4, from Alternate Recrystallization of Example 13; Generation of Solid Form 4 (Figure 6) and the calculated powder pattern, generated via Mercury software, from resolved X-ray single-crystal data of Form 4 (see Single-crystal X-ray Structural Determination of Example 13, Solid Form 4).

Figure 9: Powder X-ray Diffraction Pattern of Example 13, Solid Form 5, from Example Figure 10: Powder X-ray Diffraction Pattern of Intermediate C16, HCl salt.

Figure 11: Powder X-ray Diffraction Pattern of Intermediate C91.

Figure 12: Single-crystal X-ray Structural Determination of ediate C91. ORTEP m drawn with displacement parameters at 50% probability.

Figure 13: Powder X-ray Diffraction Pattern of Intermediate C92.

Figure 14: Powder X-ray Diffraction Pattern of Intermediate C42.

Figure 15: Single-crystal X-ray Structural Determination of Intermediate C42. ORTEP m drawn with displacement parameters at 50% probability.

Detailed Description of The Invention For the purposes of the present invention, as described and claimed , the following terms are defined as follows: As used , the terms ising” and “including” are used in their open, non-limiting sense. The term ing”, as used herein, unless otherwise indicated, means reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition. In the methods of treating COVID-19 it is to be understood that COVID-19 is the disease caused in patients by infection with the SARS-CoV-2 virus. The SARSCoV-2 virus is to be understood to encompass the initially ered strain of the virus as well as mutant strains which emerge, such as but not limited to, s such as B.1.1.7 (UK variant), B.1.351 (South African variant), P.1 (Brazilian variant) and B.1.427/B.1.429 (Califonia variants). The term “treatment”, as used herein, unless otherwise indicated, refers to the act of treating as ing” is defined immediately above.

The term “patient” refers to warm-blooded animals such as, for example, guinea pigs, mice, rats, gerbils, cats, rabbits, dogs, cattle, goats, sheep, horses, monkeys, chimpanzees, and humans. With respect to the treatment of COVID-19 the methods of the ion are particularly useful for the treatment of a human patient.

The term “pharmaceutically acceptable” means the substance or composition must be compatible, chemically and/or logically, with the other ingredients comprising a formulation, and/or the mammal being treated therewith.

The term “therapeutically effective amount” means an amount of a compound of the present invention that (i) treats or prevents the particular disease, condition, or disorder, (ii) attenuates, ameliorates, or eliminates one or more symptoms of the ular e, condition, or disorder, or (iii) prevents or delays the onset of one or more symptoms of the ular disease, condition, or disorder described herein.

The term "alkyl” as used herein refers to a linear or ed-chain saturated hydrocarbyl substituent (i.e., a substituent obtained from a hydrocarbon by removal of a hydrogen); in one embodiment containing from one to eight carbon atoms, in another one to six carbon atoms and in yet r one to three carbon atoms. Non -limiting examples of such substituents e methyl, ethyl, propyl (including yl and isopropyl), butyl (including n-butyl, isobutyl, sec-butyl and tert-butyl), pentyl, isoamyl, hexyl, heptyl, octyl and the like. In another embodiment containing one to three carbons and consisting of methyl, ethyl, n-propyl and pyl.

The term "alkynyl” as used herein refers to a linear or branched-chain saturated hydrocarbyl substituent that contains a carbon-carbon triple bond (i.e., a substituent ed from a triple bond-containing arbon by removal of a hydrogen); in one embodiment containing from two to six carbon atoms. Non-limiting examples of such substituents include propynyl, butynyl, pentynyl and hexynyl.

The term "alkoxy” refers to a linear or branched-chain saturated hydrocarbyl substituent attached to an oxygen radical (i.e., a substituent obtained from a arbon alcohol by removal of the hydrogen from the OH); in one embodiment containing from one to six carbon atoms. Non-limiting examples of such substituents include methoxy, ethoxy, y (including n-propoxy and isopropoxy), butoxy (including n-butoxy, isobutoxy, sec-butoxy and utoxy), pentoxy, hexoxy and the like. In another embodiment having one to three carbons and consisting of methoxy, ethoxy, n-propoxy and isopropoxy. An alkoxy group which is attached to an alkyl group is referred to as an alkoxyalkyl. An example of an alkoxyalkyl group is methoxymethyl.

The term "alkynyloxy” refers to a linear or branched-chain saturated hydrocarbyl substituent ning a carbon-carbon triple bond attached to an oxygen radical (i.e., a substituent obtained from a triple bond-containing hydrocarbon alcohol by removal of the hydrogen from the OH); in one embodiment containing from three to six carbon atoms. Non-limiting examples of such tuents e propynyloxy, butynyloxy and pentynyloxy and the like.

In some instances, the number of carbon atoms in a hydrocarbyl substituent (i.e., alkyl, cycloalkyl, etc.) is ted by the prefix “Cx-Cy-” or “Cx-y”, wherein x is the minimum and y is the maximum number of carbon atoms in the substituent. Thus, for example, “C1-C8 alkyl” or “C1-8 alkyl” refers to an alkyl substituent containing from 1 to 8 carbon atoms, “C1-C6 alkyl” or “C1-6 alkyl” refers to an alkyl substituent containing from 1 to 6 carbon atoms, “C1-C3 alkyl” or “C1-3 alkyl” refers to an alkyl substituent containing from 1 to 3 carbon atoms. Illustrating further, C 3-C6 cycloalkyl or C3cycloalkyl refers to a saturated cycloalkyl group containing from 3 to 6 carbon ring atoms.

The term "cycloalkyl” refers to a carbocyclic substituent ed by removing a hydrogen from a saturated carbocyclic molecule, for example one having three to seven carbon atoms. The term “cycloalkyl” includes monocyclic saturated carbocycles. The term “C3-C7 cycloalkyl” means a radical of a three- to seven-membered ring system which includes the groups cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. The term “C3-C6 cycloalkyl” means a radical of a three- to six-membered ring system which includes the groups cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. The cycloalkyl groups can also be bicyclic or yclic ycles. For example, the term “C3-C12 cycloalkyl” includes monocyclic carbocycles and bicyclic and spirocyclic cycloalkyl moieties such as bicyclopentyl, bicyclohexyl, oheptyl, bicyclooctyl, bicyclononyl, spiropentyl, exyl, spiroheptyl, spirooctyl and spirononyl.

The term “C3-C6 cycloalkoxy” refers to a three- to six-membered cycloalkyl group attached to an oxygen radical. Examples include cyclopropoxy, cyclobutoxy, cyclopentoxy and cyclohexoxy.

The term “aryl” refers to a carbocyclic aromatic system. The term “C6-C10 aryl” refers to carbocyclic aromatic systems with 3 to 10 atoms and includes phenyl and naphthyl.

In some instances, the number of atoms in a cyclic substituent containing one or more heteroatoms (i.e., heteroaryl or heterocycloalkyl) is indicated by the prefix “x- to ymembered” , wherein x is the minimum and y is the maximum number of atoms forming the cyclic moiety of the substituent. Thus, for e, “4- to 6-membered heterocycloalkyl” refers to a heterocycloalkyl containing from 4 to 6 atoms, including one to three heteroatoms, in the cyclic moiety of the heterocycloalkyl. Likewise, the phrase “5- to 6-membered heteroaryl” refers to a heteroaryl containing from 5 to 6 atoms, and “5- to bered heteroaryl” refers to a heteroaryl containing from 5 to 10 atoms, each including one or more atoms, in the cyclic moiety of the heteroaryl. Furthermore, the s “5-membered aryl” and “6-membered heteroaryl” refer to a five-membered aromatic ring system and a six-membered heteroaromatic ring system, respectively. The heteroatoms present in these ring systems are selected from N, O and S.

The term “hydroxy” or “hydroxyl” refers to –OH. When used in combination with r term(s), the prefix “hydroxy” indicates that the tuent to which the prefix is attached is substituted with one or more hydroxy substituents. Compounds bearing a carbon to which one or more hydroxy substituents include, for example, alcohols, enols and phenol. The terms cyano and nitrile refer to a -CN group. The term “oxo” means an oxygen which is attached to a carbon by a double bond (i.e., when R4 is oxo then R4 together with the carbon to which it is attached are a C=O moiety).

The term “halo” or “halogen” refers to fluorine (which may be depicted as -F), chlorine (which may be depicted as -Cl), bromine (which may be depicted as -Br), or iodine (which may be depicted as -I).

The term “heterocycloalkyl” refers to a substituent ed by removing a hydrogen from a saturated or partially saturated ring structure containing a total of the specified number of atoms, such as 4 to 6 ring atoms or 4 to 12 atoms, wherein at least one of the ring atoms is a heteroatom (i.e., oxygen, nitrogen, or ), with the remaining ring atoms being independently selected from the group consisting of carbon, , nitrogen, and sulfur. The sulfur may be oxidized [i.e., S(O) or S(O)2] or not. In a group that has a heterocycloalkyl substituent, the ring atom of the heterocycloalkyl substituent that is bound to the group may be a nitrogen heteroatom, or it may be a ring carbon atom. Similarly, if the heterocycloalkyl substituent is in turn substituted with a group or substituent, the group or substituent may be bound to a nitrogen heteroatom, or it may be bound to a ring carbon atom. It is to be understood that a heterocyclic group may be clic, bicyclic, clic or spirocyclic.

The term “heteroaryl” refers to an ic ring structure ning the specified number of ring atoms in which at least one of the ring atoms is a heteroatom (i.e., oxygen, nitrogen, or sulfur), with the remaining ring atoms being independently selected from the group consisting of carbon, oxygen, nitrogen, and sulfur. es of heteroaryl substituents include 6-membered heteroaryl substituents such as pyridyl, pyrazyl, pyrimidinyl, and pyridazinyl; and 5-membered heteroaryl substituents such as triazolyl, imidazolyl, furanyl, thiophenyl, pyrazolyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, 1,2,3-, 1,2,4-, 1,2,5-, or 1,3,4-oxadiazolyl and isothiazolyl. The aryl group can also be a ic heteroaromatic group such as l, benzofuranyl, benzothienyl, idazolyl, hiazolyl, benzoxazolyl, benzoisoxazolyl, oxazolopyridinyl, imidazopyridinyl, imidazopyrimidinyl and the like. In a group that has a heteroaryl substituent, the ring atom of the aryl substituent that is bound to the group may be one of the heteroatoms, or it may be a ring carbon atom. Similarly, if the heteroaryl substituent is in turn substituted with a group or substituent, the group or tuent may be bound to one of the heteroatoms, or it may be bound to a ring carbon atom. The term “heteroaryl” also includes pyridyl N-oxides and groups containing a pyridine N-oxide ring.

In addition, the heteroaryl group may contain an oxo group such as the one present in a pyridone group. Further examples include furyl, thienyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyridin-2(1H)-onyl, pyridazin-2(1H)-onyl, pyrimidin- 2(1H)-onyl, pyrazin-2(1H)-onyl, imidazo[1,2-a]pyridinyl, and pyrazolo[1,5-a]pyridinyl. The heteroaryl can be further substituted as defined herein.

Examples of single-ring heteroaryls and heterocycloalkyls include furanyl, dihydrofuranyl, tetrahydrofuranyl, thiophenyl, dihydrothiophenyl, tetrahydrothiophenyl, pyrrolyl, isopyrrolyl, pyrrolinyl, pyrrolidinyl, imidazolyl, isoimidazolyl, imidazolinyl, imidazolidinyl, lyl, pyrazolinyl, pyrazolidinyl, triazolyl, tetrazolyl, dithiolyl, oxathiolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, thiazolinyl, isothiazolinyl, thiazolidinyl, isothiazolidinyl, thiaoxadiazolyl, oxathiazolyl, oxadiazolyl (including oxadiazolyl, oxadiazolyl, 1,2,5-oxadiazolyl, or 1,3,4-oxadiazolyl), l ding 1,2-pyranyl or 1,4-pyranyl), dihydropyranyl, pyridinyl, piperidinyl, diazinyl ding pyridazinyl, pyrimidinyl, piperazinyl, triazinyl (including s-triazinyl, azinyl and v-triazinyl), oxazinyl (including 2H-1,2-oxazinyl, 6H-1,3-oxazinyl, or 2H- 1,4-oxazinyl), isoxazinyl (including o-isoxazinyl or p-isoxazinyl), oxazolidinyl, isoxazolidinyl, oxathiazinyl (including 1,2,5-oxathiazinyl or 1,2,6-oxathiazinyl), oxadiazinyl (including 2H-1,2,4-oxadiazinyl or 2H-1,2,5-oxadiazinyl), and morpholinyl.

The term oaryl” can also include, when specified as such, ring systems having two rings wherein such rings may be fused and wherein one ring is ic and the other ring is not fully part of the conjugated aromatic system (i.e., the heteroaromatic ring can be fused to a cycloalkyl or heterocycloalkyl ring). Non-limiting examples of such ring systems include 5,6,7,8-tetrahydroisoquinolinyl, 8- tetrahydroquinolinyl, hydro-5H-cyclopenta[b]pyridinyl, 6,7-dihydro-5H- cyclopenta[c]pyridinyl, 1,4,5,6-tetrahydrocyclopenta[c]pyrazolyl, 6- tetrahydrocyclopenta[c]pyrazolyl, 5,6-dihydro-4H-pyrrolo[1,2-b]pyrazolyl, 6,7-dihydro- 5H-pyrrolo[1,2-b][1,2,4]triazolyl, 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyridinyl, 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridinyl, 4,5,6,7-tetrahydro-1H-indazolyl and 4,5,6,7- tetrahydro-2H-indazolyl. It is to be understood that if a carbocyclic or heterocyclic moiety may be bonded or ise attached to a designated substrate h differing ring atoms without denoting a specific point of ment, then all possible points are intended, whether through a carbon atom or, for example, a trivalent nitrogen atom. For example, the term “pyridyl” means 2-, 3- or 4-pyridyl, the term “thienyl” means 2- or nyl, and so forth.

If substituents are described as “independently” having more than one variable, each instance of a substituent is selected independent of the other(s) from the list of variables available. Each substituent therefore may be identical to or different from the other substituent(s).

If substituents are described as being “independently selected” from a group, each instance of a substituent is selected independent of the other(s). Each substituent therefore may be identical to or different from the other substituent(s).

As used herein, the term “Formula I” , “Formula I’ ” or “Formula I” ” may be hereinafter referred to as a und(s) of the invention,” “the present ion,” and “compound(s) of Formula I, I’ or I”. Such terms are also defined to include all forms of the compound of a I, I’ and I” including hydrates, solvates, isomers, crystalline and non-crystalline forms, isomorphs, polymorphs, and metabolites thereof. For example, the compounds of the invention, or pharmaceutically acceptable salts thereof, may exist in unsolvated and ed forms. When the t or water is tightly bound, the complex will have a well-defined stoichiometry independent of humidity. When, however, the solvent or water is weakly bound, as in l solvates and hygroscopic compounds, the water/solvent content will be ent on humidity and drying conditions. In such cases, non-stoichiometry will be the norm.

The compounds of the invention may exist as clathrates or other complexes.

Included within the scope of the invention are complexes such as clathrates, drug-host inclusion complexes n the drug and host are present in stoichiometric or nonstoichiometric s. Also included are complexes of the compounds of the ion containing two or more organic and/or inorganic components, which may be in stoichiometric or non-stoichiometric amounts. The resulting complexes may be ionized, partially ionized, or non-ionized. For a review of such complexes, see J. Pharm. Sci., 64 (8), 1269-1288 by Haleblian (August 1975).

The compounds of the invention have asymmetric carbon atoms. The carbon bonds of the compounds of the invention may be depicted herein using a solid line ( ), a solid wedge ( ), or a dotted wedge ( ). The use of a solid line to depict bonds to asymmetric carbon atoms is meant to indicate that all possible stereoisomers (e.g., specific enantiomers, racemic mixtures, etc.) at that carbon atom are included. The use of either a solid or dotted wedge to depict bonds to asymmetric carbon atoms is meant to te that only the stereoisomer shown is meant to be included. It is possible that compounds of Formula I, I’ and I” may contain more than one asymmetric carbon atom. In those compounds, the use of a solid line to depict bonds to asymmetric carbon atoms is meant to indicate that all le stereoisomers are meant to be included. For example, unless stated otherwise, it is intended that the nds of Formula I, I’ and I” can exist as enantiomers and diastereomers or as racemates and es thereof. The use of a solid line to depict bonds to one or more asymmetric carbon atoms in a compound of Formula I, I’ and I” and the use of a solid or dotted wedge to depict bonds to other asymmetric carbon atoms in the same nd is meant to indicate that a e of diastereomers is present.

Stereoisomers of Formula I, I’ and I” include cis and trans isomers, l isomers such as R and S enantiomers, diastereomers, geometric isomers, rotational isomers, conformational isomers, and tautomers of the compounds of the invention, including compounds exhibiting more than one type of isomerism; and mixtures thereof (such as racemates and diastereomeric pairs). Also included are acid addition or base addition salts wherein the counterion is optically active, for example, D-lactate or L- , or racemic, for example, DL-tartrate or DL-arginine.

When any racemate llizes, ls of two different types are possible. The first type is the racemic compound (true racemate) ed to above wherein one homogeneous form of crystal is produced containing both omers in equimolar amounts. The second type is the racemic mixture or conglomerate wherein two forms of l are produced in equimolar amounts each comprising a single enantiomer.

The compounds of the invention such as those of Formula I, I’ and I” may exhibit the phenomenon of tautomerism; such tautomers are also regarded as compounds of the invention. All such tautomeric forms, and mixtures thereof, are included within the scope of compounds of Formula I, I’ and I”. Tautomers exist as mixtures o f a tautomeric set in solution. In solid form, usually one tautomer predominates. Even though one tautomer may be described, the present ion includes all ers of the compounds of Formula I, I’ and I” and salts thereof.

The phrase “pharmaceutically acceptable salts(s)”, as used herein, unless otherwise indicated, includes salts of acidic or basic groups which may be present in the compounds described . The compounds used in the methods of the invention that are basic in nature are capable of forming a wide variety of salts with various inorganic and organic acids. The acids that may be used to prepare pharmaceutically able acid addition salts of such basic compounds are those that form non-toxic acid addition salts, i.e., salts containing cologically acceptable anions, such as the acetate, benzenesulfonate, benzoate, bicarbonate, bisulfate, bitartrate, borate, bromide, calcium edetate, camsylate, carbonate, chloride, clavulanate, citrate, dihydrochloride, edetate, edislyate, estolate, esylate, ethylsuccinate, te, tate, gluconate, ate, hexylresorcinate, amine, hydrobromide, hydrochloride, iodide, isethionate, lactate, lactobionate, laurate, malate, maleate, mandelate, mesylate, methylsulfate, mucate, napsylate, nitrate, oleate, oxalate, pamoate (embonate), palmitate, pantothenate, phosphate/diphosphate, polygalacturonate, salicylate, stearate, subacetate, ate, tannate, tartrate, teoclate, te, triethiodode, and valerate salts.

With respect to the compounds of the invention used in the methods of the invention, if the compounds also exist as tautomeric forms then this invention relates to those tautomers and the use of all such tautomers and mixtures thereof.

The subject invention also includes compounds and methods of treatment of coronavirus infections such as COVID-19 and methods of inhibiting SARS-CoV-2 with isotopically labelled compounds, which are identical to those recited herein, but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number ent from the atomic mass or mass number usually found in nature.

Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine and chlorine, such as 2H, 3H, 13C, 14C, 15N, 18O, 17O, 31P, 32P, 35S, 18F, and 36CI, tively.

Compounds of the present invention, prodrugs thereof, and pharmaceutically acceptable salts of said compounds or of said prodrugs which contain the aforementioned isotopes and/or es of other atoms are with the scope of this ion. Certain isotopically ed compounds of the present invention, for example those into which radioactive isotopes such as 3H and 14C are incorporated, are useful in drug and/or substrate tissue distribution . Tritiated, i.e., 3H, and carbon-14, i.e., 14C, isotopes are particularly preferred for their ease of preparation and detectability.

Further, substitution with heavier isotopes such as deuterium, i.e., 2H, can afford certain therapeutic advantages resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirements and, hence, may be preferred in some circumstances. Isotopically labelled compounds used in the methods of this invention and prodrugs thereof can generally be prepared by carrying out the procedures for ing the compounds disclosed in the art by substituting a readily available isotopically labelled reagent for a non-isotopically labelled t.

This ion also encompasses methods using pharmaceutical compositions and methods of treating coronavirus infections such as COVID-19 infections through administering prodrugs of compounds of the invention. Compounds having free amino, amido or hydroxy groups can be ted into prodrugs. Prodrugs include compounds wherein an amino acid residue, or a polypeptide chain of two or more (e.g., two, three or four) amino acid residues is covalently joined through an ester bond to a y of compounds used in the methods of this invention. The amino acid residues include but are not limited to the 20 naturally occurring amino acids commonly designated by three letter symbols and also e oxyproline, hydroxylysine, desmosine, isodesmosine, 3-methylhistidine, norvalin, beta-alanine, gamma-aminobutyric acid, citrulline, homocysteine, homoserine, ornithine and methionine sulfone. Additional types of prodrugs are also encompassed. For instance, free hydroxy groups may be tized using groups including but not limited to ccinates, phosphate , dimethylaminoacetates, and phosphoryloxymethyloxycarbonyls, as outlined in ed Drug Delivery Reviews, 1996, 19, 115. Carbamate prodrugs of hydroxy and amino groups are also included, as are carbonate prodrugs, sulfonate esters and sulfate esters of y groups. Derivatization of hydroxy groups as (acyloxy)methyl and (acyloxy)ethyl ethers wherein the acyl group may be an alkyl ester, optionally substituted with groups including but not limited to ether, amine and carboxylic acid functionalities, or where the acyl group is an amino acid ester as described above, are also encompassed. Prodrugs of this type are described in J. Med. Chem., 1996, 29, . Free amines can also be derivatized as amides, amides or phosphonamides.

All of these prodrug moieties may incorporate groups ing but not limited to ether, amine and carboxylic acid functionalities.

The compounds of the present invention can be used in the s of the invention in combination with other drugs. For e, dosing a SARS-CoV-2 coronavirus-infected patient (i.e., a patient with COVID-19) with the SARS-CoV-2 coronavirus 3CL protease inhibitor of the invention and an interferon, such as interferon alpha, or a pegylated interferon, such as tron or Pegasus, may e a greater clinical benefit than dosing either the interferon, pegylated interferon or the SARS-CoV- 2 coronavirus inhibitor alone. Other additional agents that can be used in the methods of the present invention include thasone, azithromycin and ivir.

Examples of greater clinical benefits could include a larger reduction in COVID-19 symptoms, a faster time to alleviation of symptoms, reduced lung pathology, a larger reduction in the amount of SARS-CoV-2 coronavirus in the patient (viral load), and decreased mortality.

The SARS-CoV-2 coronavirus infects cells which express P-glycoprotein. Some of the SARS-CoV-2 coronavirus 3CL protease inhibitors of the invention are P- glycoprotein substrates. Compounds which inhibit the SARS-CoV-2 virus which are also P-glycoprotein substrates may be dosed with a P-glycoprotein inhibitor.

Examples of P-glycoprotein inhibitors are verapamil, vinblastine, ketoconazole, nelfinavir, ritonavir or cyclosporine. The P-glycoprotein inhibitors act by inhibiting the efflux of the SARS-CoV-2 virus inhibitors of the invention out of the cell. The inhibition of the P-glycoprotein-based efflux will prevent reduction of ellular concentrations of the SARS-CoV-2 coronavirus inhibitor due to P-glycoprotein efflux.

Inhibition of the P-glycoprotein efflux will result in larger intracellular concentrations of the oV-2 coronavirus inhibitors. Dosing a SARS-CoV-2 coronavirus-infected patient with the SARS-CoV-2 coronavirus 3CL protease inhibitors of the invention and a P-glycoprotein inhibitor may lower the amount of SARS-CoV-2 coronavirus 3CL protease inhibitor required to achieve an efficacious dose by sing the ellular concentration of the SARS-CoV-2 coronavirus 3CL se inhibitor.

Among the agents that may be used to increase the exposure of a mammal to a compound of the present invention are those that can act as inhibitors of at least one isoform of the cytochrome P450 (CYP450) enzymes. The isoforms of CYP450 that may be beneficially inhibited include, but are not limited to CYP1A2, CYP2D6, CYP2C9, CYP2C19 and . The compounds used in the methods of the invention include compounds that may be CYP3A4 ates and are metabolized by CYP3A4. Dosing a SARS-CoV-2 virus-infected patient with a SARS-CoV-2 coronavirus inhibitor which is a CYP3A4 substrate, such as SARS-CoV-2 coronavirus 3CL protease inhibitor, and a CYP3A4 inhibitor, such as ritonavir, avir or delavirdine, will reduce the metabolism of the oV-2 coronavirus inhibitor by . This will result in reduced clearance of the SARS-CoV-2 virus tor and sed SARS-CoV- 2 coronavirus inhibitor plasma concentrations. The reduced clearance and higher plasma concentrations may result in a lower efficacious dose of the SARS-CoV-2 coronavirus inhibitor.

Additional therapeutic agents that can be used in combination with the SARS-CoV-2 inhibitors in the methods of the present invention include the following: PLpro inhibitors, Apilomod, EIDD-2801, Ribavirin, Valganciclovir, β-Thymidine, Aspartame, Oxprenolol, Doxycycline, Acetophenazine, Iopromide, Riboflavin, Reproterol, 2,2′-Cyclocytidine, Chloramphenicol, Chlorphenesin carbamate, Levodropropizine, Cefamandole, Floxuridine, Tigecycline, Pemetrexed, scorbic acid, Glutathione, Hesperetin, Ademetionine, Masoprocol, Isotretinoin, lene, Sulfasalazine Anti-bacterial, Silybin, Nicardipine, Sildenafil, Platycodin, Chrysin, Neohesperidin, Baicalin, Sugetriol-3,9-diacetate, (–)-Epigallocatechin gallate, Phaitanthrin D, 2-(3,4-Dihydroxyphenyl)[[2-(3,4-dihydroxyphenyl)-3,4-dihydro-5,7- dihydroxy-2Hbenzopyranyl]oxy]-3,4-dihydro-2Hbenzopyran-3,4,5,7-tetrol, 2,2- di(3-indolyl)indolone, (S)-(1S,2R,4aS,5R,8aS)Formamido-1,4a-dimethyl ene((E)(2-oxo-2,5-dihydrofuranyl)ethenyl)decahydronaphthalenyl aminophenylpropanoate, Piceatannol, Rosmarinic acid, and Magnolol. 3CLpro inhibitors, Lymecycline, Chlorhexidine, Alfuzosin, Cilastatin, dine, Almitrine, Progabide, Nepafenac, Carvedilol, Amprenavir, Tigecycline, Montelukast, Carminic acid, ne, Flavin, Lutein, Cefpiramide, Phenethicillin, Candoxatril, Nicardipine, Estradiol te, Pioglitazone, Conivaptan, Telmisartan, Doxycycline, racycline, (1S,2R,4aS,5R,8aS)Formamido-1,4a-dimethylmethylene((E)- 2-(2-oxo-2,5-dihydrofuranyl)ethenyl)decahydronaphthalenyl5-((R)-1,2-dithiolan yl) pentanoate, Betulonal, ChrysinO-β-glucuronide, Andrographiside, (1S,2R,4aS,5R,8aS)Formamido-1,4a-dimethylmethylene((E)(2-oxo-2,5- dihydrofuranyl)ethenyl)decahydronaphthalenyl 2-nitrobenzoate, 2β-Hydroxy-3,4- seco-friedelolactoneoic acid (S)-(1S,2R,4aS,5R,8aS)Formamido-1,4a-dimethyl- 6-methylene((E)(2-oxo-2,5-dihydrofuranyl)ethenyl) decahydronaphthalenyl- 2-aminophenylpropanoate, Isodecortinol, Cerevisterol, Hesperidin, Neohesperidin, Andrograpanin, 2-((1R,5R,6R,8aS)Hydroxy(hydroxymethyl)-5,8a-dimethyl methylenedecahydronaphthalenyl)ethyl benzoate, Cosmosiin, Cleistocaltone A, 2,2-Di(3-indolyl)indolone, in, Gnidicin, emblinol, Theaflavin 3,3′-di-O- gallate, inic acid, Kouitchenside I, Oleanolic acid, Stigmastenol, Deacetylcentapicrin, and Berchemol.

RdRp inhibitors, Valganciclovir, Chlorhexidine, Ceftibuten, Fenoterol, Fludarabine, Itraconazole, Cefuroxime, Atovaquone, Chenodeoxycholic acid, Cromolyn, Pancuronium bromide, Cortisone, ne, ocin, Silybin, Idarubicin Bromocriptine, Diphenoxylate, penicilloyl G, Dabigatran etexilate, Betulonal, Gnidicin, 2β,30β-Dihydroxy-3,4-seco-friedelolactonelactone, 14-Deoxy-11,12-didehydroandrographolide, Gniditrin, Theaflavin 3,3′-di-O-gallate, (R)- ((1R,5aS,6R,9aS)-1,5a-Dimethylmethyleneoxo((E)(2-oxo-2,5-dihydrofuran- 3-yl)ethenyl)decahydro-1H-benzo[c]azepinyl)methyl2-aminophenylpropanoate, 2β-Hydroxy-3,4-seco-friedelolactoneoic acid, 2-(3,4-Dihydroxyphenyl)[[2-(3,4- dihydroxyphenyl)-3,4-dihydro-5,7-dihydroxy-2Hbenzopyranyl]oxy]-3,4-dihydro-2H- 1-benzopyran-3,4,5,7-tetrol, Phyllaemblicin B, 14-hydroxycyperotundone, Andrographiside, 2-((1R,5R,6R,8aS)Hydroxy(hydroxymethyl)-5,8a-dimethyl methylenedecahydro naphthalenyl)ethyl benzoate, Andrographolide, Sugetriol-3,9- ate, Baicalin, (1S,2R,4aS,5R,8aS)Formamido-1,4a-dimethylmethylene ((E)(2-oxo-2,5-dihydrofuranyl)ethenyl)decahydronaphthalenyl -((R)-1,2-dithiolanyl)pentanoate, 1,7-Dihydroxymethoxyxanthone, 1,2,6- Trimethoxy[(6-O-β-D-xylopyranosyl-β-D-glucopyranosyl)oxy]-9H-xanthenone, and hydroxymethoxy[(6-O-β-D-xylopyranosyl-β-D-glucopyranosyl)oxy]-9H- xanthenone, 8-(β-D-Glucopyranosyloxy)-1,3,5-trihydroxy-9H-xanthenone, Additional therapeutic agents that can be used in the methods of the invention include Diosmin, Hesperidin, MK-3207, Venetoclax, oergocristine, Bolazine, R428, Ditercalinium, Etoposide, Teniposide, UK-432097, Irinotecan, Lumacaftor, Velpatasvir, Eluxadoline, Ledipasvir, Lopinavir / Ritonavir + Ribavirin, Alferon, and prednisone. Other additional agents useful in the methods of the t invention include dexamethasone, azithromycin and remdesivir as well as boceprevir, umifenovir and favipiravir.

Other additional agents that can be used in the methods of the present invention include -ketoamides compounds designated as 11r, 13a and 13b, shown below, as described in Zhang, L.; Lin, D.; Sun, X.; Rox, K.; Hilgenfeld, R.; X-ray Structure of Main Protease of the Novel Coronavirus oV-2 Enables Design of -Ketoamide Inhibitors; bioRxiv nt doi: https://doi.org/10.1101/2020.02.17.952879 Additional agents that can be used in the methods of the present invention include RIG 1 pathway activators such as those described in US Patent No. 9,884,876.

Other additional eutic agents include protease inhibitors such as those described in Dai W, Zhang B, Jiang X-M, et al. Structure-based design of antiviral drug candidates targeting the oV-2 main protease. Science. 68(6497):1331 - 1335 including compounds such as the compound shown below and a compound designated as DC402234 Another embodiment of the present invention is a method of treating COVID-19 in a patient wherein in addition to administering a compound of the t invention (i.e. a compound of Formula I, I’ or I” or a solvate or hydrate thereof or a pharmaceutically able salt of the compound or solvate or hydrate thereof) an additional agent is administered and the additional agent is selected from antivirals such as remdesivir, sivir, favilavir/avifavir, molnupiravir (MK-4482/EIDD 2801), AT-527, AT-301, BLD-2660, favipiravir, camostat, SLV213 emtrictabine/tenofivir, clevudine, dalcetrapib, evir and ABX464, orticoids such as dexamethasone and hydrocortisone, convalescent plasma, a recombinant human plasma such as gelsolin (Rhu-p65N), monoclonal antibodies such as regdanvimab (Regkirova), ravulizumab (Ultomiris), VIR-7831/VIR-7832, BRII-196/BRII-198, COVIAMG /COVI DROPS 020), ivimab (LY-CoV555), imab, leronlimab (PRO140), AZD7442, lenzilumab, infliximab, adalimumab, JS 016, STI-1499 UARD), lanadelumab (Takhzyro), canakinumab (Ilaris), gimsilumab and otilimab, antibody cocktails such as casirivimab/imdevimab Cov2), recombinant fusion protein such as MK-7110 (CD24Fc/SACCOVID), anticoagulants such as heparin and apixaban, IL-6 receptor agonists such as tocilizumab (Actemra) and sarilumab (Kevzara), e tors such as apilimod dimesylate, RIPK1 tors such as DNL758, DC402234, VIP receptor agonists such as PB1046, SGLT2 inhibitors such as dapaglifozin, TYK inhibitors such as abivertinib, kinase inhibitors such as ATR-002, tinib, acalabrutinib, losmapimod, baricitinib and tofacitinib, H2 blockers such as famotidine, anthelmintics such as niclosamide, furin inhibitors such as diminazene.

The term “SARS-CoV-2 inhibiting agent” means any SARS-CoVrelated coronavirus 3C-like protease inhibitor compound described herein or a pharmaceutically acceptable salt, hydrate, prodrug, active metabolite or solvate thereof or a compound which inhibits replication of SARS-CoV-2 in any manner.

The term “interfering with or preventing” SARS-CoVrelated coronavirus (“SARS-CoV-2”) viral replication in a cell means to reduce SARS-CoV-2 replication or production of SARS-CoV-2 components necessary for progeny virus in a cell treated with a compound of this invention as compared to a cell not being treated with a compound of this invention. Simple and convenient assays to determine if SARS-CoV- 2 viral replication has been reduced include an ELISA assay for the presence, absence, or reduced presence of anti-SARS-CoV-2 antibodies in the blood of the subject f, et al., PNAS 88:5462-5466, 1991), RT-PCR (Yu, et al., in Viral Hepatitis and Liver Disease 574-577, Nishioka, Suzuki and o (Eds.); Springer-Verlag, Tokyo, 1994).

Such methods are well known to those of ordinary skill in the art. atively, total RNA from transduced and infected “control” cells can be isolated and subjected to analysis by dot blot or northern blot and probed with SARS-CoVspecific DNA to determine if oV-2 replication is reduced. Alternatively, reduction of SARS-CoV- 2 protein expression can also be used as an indicator of tion of SARS-CoV-2 replication. A greater than fifty percent reduction in SARS-CoV-2 replication as ed to control cells typically quantitates a prevention of SARS-CoV-2 replication.

If a SARS-CoV-2 inhibitor compound used in the method of the invention is a base, a desired salt may be prepared by any suitable method known to the art, including treatment of the free base with an inorganic acid (such as hydrochloric acid, hydrobromic acid, ic acid, nitric acid, phosphoric acid, and the like), or with an organic acid (such as acetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, malonic acid, c acid, oxalic acid, glycolic acid, salicylic acid, pyranosidyl acid (such as glucuronic acid or galacturonic acid), alpha-hydroxy acid (such as citric acid or tartaric acid), amino acid (such as ic acid or glutamic acid), aromatic acid (such as c acid or cinnamic acid), sulfonic acid (such as p-toluenesulfonic acid or ethanesulfonic acid), and the like.

If a SARS-CoV-2 inhibitor compound used in the method of the invention is an acid, a desired salt may be prepared by any suitable method known to the art, including treatment of the free acid with an inorganic or organic base [such as an amine (primary, secondary, or tertiary)], an alkali metal hydroxide, or alkaline earth metal hydroxide.

Illustrative examples of le salts include organic salts derived from amino acids (such as glycine and arginine), ammonia, y amines, secondary amines, ry amines, and cyclic amines (such as piperidine, morpholine, and piperazine), as well as inorganic salts d from , m, potassium, magnesium, manganese, iron, copper, zinc, aluminum and lithium.

In the case of SARS-CoV-2 inhibitor compounds, prodrugs, salts, or solvates that are , it is understood by those skilled in the art that the compound, prodrugs, salts, and solvates used in the method of the invention, may exist in different polymorph or crystal forms, all of which are intended to be within the scope of the present invention and specified formulas. In addition, the compound, salts, prodrugs and solvates used in the method of the invention may exist as tautomers, all of which are intended to be within the broad scope of the present invention.

Solubilizing agents may also be used with the compounds of the invention to increase the compounds’ solubility in water of logically acceptable solutions.

These solubilizing agents include cyclodextrins, propylene glycol, diethylacetamide, polyethylene glycol, Tween, ethanol and micelle-forming agents. Offered solubilizing agents are cyclodextrins, particularly beta-cyclodextrins and in ular hydroxypropyl beta-cyclodextrin and sulfobutylether beta-cyclodextrin.

In some cases, the SARS-CoV-2 inhibitor compounds, salts, prodrugs and solvates used in the method of the invention may have chiral centers. When chiral centers are present, the compound, salts, prodrugs and solvates may exist as single stereoisomers, racemates, and/or mixtures of enantiomers and/or reomers. All such single stereoisomers, racemates, and mixtures thereof are intended to be within the broad scope of the present invention.

As generally tood by those skilled in the art, an optically pure nd is one that is enantiomerically pure. As used herein, the term “optically pure” is intended to mean a compound sing at least a sufficient activity. Preferably, an optically pure amount of a single enantiomer to yield a nd having the desired pharmacologically pure nd of the invention comprises at least 90% of a single isomer (80% enantiomeric excess), more preferably at least 95% (90% e.e.), even more preferably at least 97.5% (95% e.e.), and most preferably at least 99% (98% e.e.).

The term “treating”, as used herein, unless otherwise indicated, means reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition.

The term “treatment”, as used herein, unless otherwise indicated, refers to the act of treating as “treating” is defined immediately above. In a preferred ment of the present invention, “treating” or “treatment” means at least the mitigation of a disease condition in a human, that is alleviated by the inhibition of the activity of the SARS-CoV- 2 3C-like protease which is the main protease of SARS-CoV-2, the ive agent for COVID-19. For patients ing from COVID-19, fever, fatigue, and dry cough are the main manifestations of the disease, while nasal congestion, runny nose, and other symptoms of the upper respiratory tract are rare. Beijing Centers for Diseases Control and Prevention indicated that the typical case of COVID-19 has a progressive aggravation process. COVID-19 can be classified into light, , severe, and critical types based on the severity of the disease. al Health Commission of the People’s Republic of China. Diagnosis and Treatment of Pneumonia Caused by 2019-nCoV (Trial Version 4). Available online: http://www.nhc.gov.cn/jkj/s3577/202002/573340613ab243b3a7f61df260551dd4/files/c7 91e5a7ea5149f680fdcb34dac0f54e.pdf : (1) Mild cases—the clinical symptoms were mild, and no pneumonia was found on the chest computed tomography (CT); (2) normal cases—fever, respiratory symptoms, and patients found to have imaging manifestations of pneumonia; (3) severe one of the following three ions: Respiratory distress, respiratory rate ≥ 30 times / min (in resting state, refers to oxygen saturation ≤ 93%), partial arterial oxygen pressure (PaO2)/oxygen absorption tration (FiO2) ≤300 mmHg (1 mm Hg = 0.133 kPa); (4) critical one of the following three conditions: atory failure and the need for ical ventilation, shock, or the associated failure of other organs requiring the intensive care unit. The current clinical data shows that the majority of deaths ed in the older patients. However, severe cases have been documented in young adults who have unique factors, particularly those with chronic diseases, such as diabetes or hepatitis B. Those with a long-term use of hormones or immunosuppressants, and decreased immune function, are likely to get severely infected.

Methods of treatment for mitigation of a coronavirus disease condition such as COVID-19 include the use of one or more of the compounds of the invention in any conventionally able manner. According to certain preferred embodiments of the invention, the compound or compounds used in the s of the present invention are administered to a , such as a human, in need thereof. Preferably, the mammal in need thereof is infected with a coronavirus such as the causative agent of COVID-19, namely SARS-CoV-2.

The present invention also includes prophylactic methods, comprising administering an effective amount of a SARS-CoV-2 inhibitor of the invention, or a pharmaceutically acceptable salt, prodrug, pharmaceutically active metabolite, or solvate thereof to a mammal, such as a human at risk for infection by SARS-CoV-2.

According to certain preferred embodiments, an effective amount of one or more compounds of the invention, or a pharmaceutically acceptable salt, prodrug, pharmaceutically active metabolite, or solvate f is administered to a human at risk for infection by SARS-CoV-2, the causative agent for COVID-19. The prophylactic methods of the invention include the use of one or more of the compounds in the invention in any tionally acceptable .

Certain of the compounds used in the methods of the invention, for example dexamethasone, azithromycin and remdesivir are known and can be made by methods known in the art.

Recent ce indicates that a new coronavirus SARS-CoV-2 is the ive agent of COVID-19. The nucleotide sequence of the SARS-CoV-2 coronavirus as well as the recently determined L- and S- subtypes have recently been determined and made publicly ble.

The activity of the inhibitor compounds as inhibitors of SARS-CoV-2 viral activity may be measured by any of the suitable methods available in the art, including in vivo and in vitro assays. The activity of the compounds of the present invention as inhibitors of coronavirus 3C-like protease activity (such as the 3C-like protease of the SARS-CoV- 2 coronavirus) may be measured by any of the le s known to those skilled in the art, including in vivo and in vitro assays. Examples of suitable assays for activity measurements include the antiviral cell culture assays described herein as well as the antiprotease assays described herein, such as the assays described in the Experimental section. stration of the SARS-CoV-2 inhibitor compounds and their pharmaceutically acceptable prodrugs, salts, active lites, and solvates may be performed according to any of the ed modes of administration available to those skilled in the art. Illustrative examples of le modes of administration include oral, nasal, pulmonary, eral, topical, intravenous, injected, transdermal, and rectal.

Oral, intravenous, aneous and nasal deliveries are preferred.

A SARS-CoVinhibiting agent may be administered as a pharmaceutical composition in any suitable pharmaceutical form. Suitable pharmaceutical forms include solid, semisolid, liquid, or lyophilized formulations, such as tablets, s, capsules, suppositories, suspensions, liposomes, and aerosols. The SARS-CoV inhibiting agent may be prepared as a solution using any of a variety of methodologies.

For example, SARS-CoVinhibiting agent can be dissolved with acid (e.g., 1 M HCI) and diluted with a ient volume of a solution of 5% dextrose in water (D5W) to yield the desired final concentration of SARS-CoVinhibiting agent (e.g., about 15 mM).

Alternatively, a solution of D5W containing about 15 mM HCI can be used to provide a solution of the SARS-CoVinhibiting agent at the appropriate concentration. Further, the SARS-CoVinhibiting agent can be prepared as a suspension using, for example, a 1% solution of carboxymethylcellulose (CMC).

Acceptable methods of preparing suitable pharmaceutical forms of the pharmaceutical itions are known or may be routinely determined by those skilled in the art. For example, pharmaceutical preparations may be prepared following conventional techniques of the pharmaceutical t involving steps such as mixing, granulating, and compressing when necessary for tablet forms, or mixing, filling and dissolving the ingredients as appropriate, to give the desired products for intravenous, oral, parenteral, topical, intravaginal, intranasal, intrabronchial, intraocular, intraaural, and/or rectal administration.

Typically, a compound of the ion is stered in an amount effective to treat a condition as described . The compounds of the invention are administered by any suitable route in the form of a pharmaceutical composition adapted to such a route, and in a dose ive for the treatment intended. Therapeutically effective doses of the compounds required to treat the progress of the medical condition are readily ascertained by one of ordinary skill in the art using preclinical and clinical approaches familiar to the medicinal arts.

The compounds of the invention may be administered orally. Oral administration may involve swallowing, so that the compound enters the gastrointestinal tract, or buccal or gual administration may be employed, by which the compound enters the blood stream directly from the mouth.

In another embodiment, the nds of the invention may also be administered directly into the blood stream, into muscle, or into an internal organ.

Suitable means for parenteral administration include intravenous, intraarterial, intraperitoneal, intrathecal, intraventricular, intraurethral, intrasternal, intracranial, intramuscular and aneous. Suitable devices for parenteral administration include needle (including microneedle) injectors, needle-free injectors and infusion techniques.

In another embodiment, the nds of the invention may also be administered topically to the skin or mucosa, that is, dermally or transdermally. In r embodiment, the nds of the invention can also be administered intranasally or by inhalation. In another embodiment, the nds of the invention may be administered rectally or lly. In another embodiment, the compounds of the invention may also be administered directly to the eye or ear.

The dosage n for the compounds and/or compositions containing the compounds is based on a variety of factors, ing the type, age, weight, sex and medical condition of the patient; the severity of the condition; the route of administration; and the activity of the particular compound employed. Thus the dosage regimen may vary widely. Dosage levels of the order from about 0.01 mg to about 100 mg per kilogram of body weight per day are useful in the treatment of the above- indicated conditions. In one embodiment, the total daily dose of a compound of the invention (administered in single or divided doses) is typically from about 0.01 to about 100 mg/kg. In another embodiment, total daily dose of the compound of the ion is from about 0.1 to about 50 mg/kg, and in another embodiment, from about 0.5 to about 30 mg/kg (i.e., mg compound of the invention per kg body weight). In one embodiment, dosing is from 0.01 to 10 day. In another embodiment, dosing is from 0.1 to 1.0 mg/kg/day. Dosage unit compositions may contain such amounts or submultiples thereof to make up the daily dose. In many instances, the administration of the compound will be repeated a plurality of times in a day (typically no r than 4 times). Multiple doses per day typically may be used to increase the total daily dose, if desired.

For oral administration, the compositions may be provided in the form of tablets containing from about 0.01 mg to about 500 mg of the active ingredient, or in another embodiment, from about 1 mg to about 100 mg of active ingredient. Intravenously, doses may range from about 0.1 to about 10 mg/kg/minute during a constant rate infusion.

Suitable ts according to the present invention include mammalian patients. s according to the present invention include, but are not limited to, canine, feline, bovine, e, equine, ovine, porcine, s, lagomorphs, primates, and the like, and encompass mammals in utero. In one embodiment, humans are suitable ts. Human patients may be of either gender and at any stage of development.

In another embodiment, the invention comprises the use of one or more compounds of the invention for the preparation of a medicament for the treatment of the conditions recited herein.

For the treatment of the conditions referred to above, the nd of the invention can be administered as compound per se. Alternatively, pharmaceutically able salts are suitable for medical applications because of their greater aqueous solubility relative to the parent compound.

In another embodiment, the present invention comprises ceutical compositions. Such pharmaceutical itions comprise a compound of the invention presented with a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier encompasses any suitable dosage form that is acceptable for administration to a patient. The r can be a solid, a liquid, or both, and may be formulated with the compound as a unit-dose ition, for example, a tablet, which can contain from 0.05% to 95% by weight of the active compounds. A compound of the invention may be d with suitable polymers as targetable drug carriers. Other pharmacologically active substances can also be present.

The compounds of the present invention may be administered by any suitable route, preferably in the form of a pharmaceutical composition adapted to such a route, and in a dose effective for the treatment intended. The active compounds and compositions, for example, may be administered orally, rectally, parenterally, or topically.

Oral administration of a solid dose form may be, for example, presented in discrete units, such as hard or soft capsules, pills, cachets, lozenges, or tablets, each containing a predetermined amount of at least one compound of the present invention.

In another embodiment, the oral administration may be in a powder or granule form. In another embodiment, the oral dose form is sub-lingual, such as, for example, a lozenge.

In such solid dosage forms, the compounds of the ion are ordinarily ed with one or more adjuvants. Such capsules or tablets may contain a controlled-release ation. In the case of capsules, tablets, and pills, the dosage forms also may comprise buffering agents or may be prepared with enteric coatings.

In another embodiment, oral administration may be in a liquid dose form. Liquid dosage forms for oral administration include, for example, pharmaceutically acceptable emulsions, ons, sions, syrups, and elixirs containing inert diluents commonly used in the art (e.g., water). Such compositions also may comprise nts, such as wetting, emulsifying, suspending, flavoring (e.g., sweetening), and/or perfuming agents.

In another embodiment, the present invention comprises a parenteral dose form.

"Parenteral administration" includes, for e, subcutaneous injections, intravenous injections, intraperitoneal injections, intramuscular injections, intrasternal injections, and on. Injectable preparations (e.g., sterile able aqueous or oleaginous suspensions) may be ated according to the known art using suitable dispersing, wetting agents, and/or suspending agents.

In another embodiment, the present invention comprises a l dose form.

"Topical administration" includes, for example, transdermal stration, such as via transdermal s or iontophoresis devices, intraocular administration, or intranasal or inhalation administration. Compositions for topical administration also e, for example, topical gels, sprays, ointments, and creams. A topical formulation may include a compound which enhances absorption or ation of the active ingredient through the skin or other affected areas. When the compounds of this invention are administered by a transdermal device, administration will be accomplished using a patch either of the reservoir and porous membrane type or of a solid matrix variety. l formulations for this purpose include gels, hydrogels, lotions, solutions, creams, ointments, dusting powders, dressings, foams, films, skin s, wafers, implants, sponges, fibers, bandages and microemulsions. mes may also be used. Typical carriers include alcohol, water, mineral oil, liquid petrolatum, white petrolatum, glycerin, polyethylene glycol and propylene glycol. Penetration enhancers may be incorporated; see, for example, J. Pharm. Sci., 88 (10), 955-958, by Finnin and Morgan (October 1999).

Formulations suitable for l administration to the eye include, for example, eye drops wherein the compound of this invention is dissolved or suspended in a suitable carrier. A typical ation suitable for ocular or aural stration may be in the form of drops of a micronized suspension or solution in isotonic, pH-adjusted, sterile saline. Other formulations suitable for ocular and aural administration include ointments, biodegradable (e.g., absorbable gel sponges, collagen) and non- biodegradable (e.g., silicone) implants, wafers, lenses and particulate or vesicular s, such as niosomes or liposomes. A polymer such as cross-linked polyacrylic acid, polyvinyl alcohol, onic acid, a cellulosic polymer, for example, hydroxypropylmethyl cellulose, hydroxyethyl cellulose, or methyl cellulose, or a heteropolysaccharide polymer, for example, gelan gum, may be orated together with a preservative, such as benzalkonium chloride. Such ations may also be delivered by iontophoresis.

For asal administration or administration by inhalation, the active nds of the invention are conveniently red in the form of a solution or suspension from a pump spray container that is squeezed or pumped by the patient or as an aerosol spray presentation from a pressurized ner or a nebulizer, with the use of a suitable propellant. Formulations suitable for intranasal administration are typically administered in the form of a dry powder (either alone, as a mixture, for example, in a dry blend with lactose, or as a mixed component particle, for example, mixed with phospholipids, such as phosphatidylcholine) from a dry powder inhaler or as an aerosol spray from a pressurized container, pump, spray, er (preferably an atomizer using electrohydrodynamics to produce a fine mist), or nebulizer, with or without the use of a suitable propellant, such as 1,1,1,2-tetrafluoroethane or 1,1,1,2,3,3,3-heptafluoropropane. For intranasal use, the powder may comprise a bioadhesive agent, for example, chitosan or cyclodextrin.

In another embodiment, the present invention comprises a rectal dose form.

Such rectal dose form may be in the form of, for example, a suppository. Cocoa butter is a traditional suppository base, but various alternatives may be used as appropriate.

Other r materials and modes of stration known in the pharmaceutical art may also be used. Pharmaceutical compositions of the invention may be prepared by any of the well-known techniques of pharmacy, such as effective formulation and administration procedures. The above considerations in regard to effective formulations and administration procedures are well known in the art and are bed in standard oks. Formulation of drugs is discussed in, for example, Hoover, John E., Remington’s Pharmaceutical Sciences, Mack Publishing Co., Easton, lvania, 1975; Liberman et al., Eds., Pharmaceutical Dosage Forms, Marcel Decker, New York, N.Y., 1980; and Kibbe et al., Eds., Handbook of Pharmaceutical ents (3rd Ed.), American Pharmaceutical Association, Washington, 1999.

The nds of the present invention can be used, alone or in combination with other therapeutic agents, in the treatment of various conditions or e states. The compound(s) of the present invention and other therapeutic agent(s) may be administered simultaneously (either in the same dosage form or in te dosage forms) or sequentially. Two or more compounds may be administered simultaneously, concurrently or sequentially. Additionally, simultaneous administration may be d out by mixing the compounds prior to administration or by administering the compounds at the same point in time but at different anatomic sites or using different routes of administration. The phrases “concurrent administration,” “co-administration,” “simultaneous administration,” and “administered simultaneously” mean that the compounds are administered in combination.

The present ion includes the use of a combination of a compound of the invention and one or more onal therapeutic agent(s). If a combination of active agents is administered, then they may be stered sequentially or simultaneously, in separate dosage forms or combined in a single dosage form. Accordingly, the present invention also includes pharmaceutical compositions comprising an amount of: (a) a first agent comprising a compound of the invention or a pharmaceutically acceptable salt of the nd; (b) a second therapeutic agent; and (c) a pharmaceutically acceptable r. Pharmaceutical compositions of the invention may also include suitable ents, diluents, vehicles, and carriers, as well as other pharmaceutically active agents, depending upon the intended use. Solid or liquid pharmaceutically acceptable carriers, diluents, vehicles, or excipients may be employed in the pharmaceutical compositions. Illustrative solid carriers e starch, lactose, calcium sulfate dihydrate, terra alba, sucrose, talc, gelatin, pectin, acacia, magnesium stearate, and stearic acid. Illustrative liquid carriers include syrup, peanut oil, olive oil, saline solution, and water. The carrier or diluent may include a le prolongedrelease al, such as glyceryl earate or glyceryl distearate, alone or with a wax. When a liquid carrier is used, the preparation may be in the form of a syrup, elixir, emulsion, soft gelatin capsule, sterile injectable liquid (e.g., solution), or a nonaqueous or aqueous liquid suspension.

A dose of the pharmaceutical composition may contain at least a therapeutically effective amount of a SARS-CoVinhibiting agent and preferably is made up of one or more pharmaceutical dosage units. The selected dose may be administered to a , for e, a human patient, in need of treatment ed by tion of SARS-CoV-2 related coronavirus activity, by any known or suitable method of administering the dose, including topically, for example, as an ointment or cream; orally; rectally, for example, as a suppository; parenterally by injection; intravenously; or continuously by intravaginal, asal, intrabronchial, intraaural, or intraocular infusion.

The phrases “therapeutically effective amount” and “effective amount” are intended to mean the amount of an ive agent that, when stered to a mammal in need of treatment, is sufficient to effect treatment for injury or disease conditions alleviated by the inhibition of SARS-CoV-2 viral replication. The amount of a given SARS-CoVinhibiting agent used in the method of the invention that will be therapeutically effective will vary depending upon factors such as the particular SARSCoVinhibiting agent, the disease condition and the severity thereof, the identity and characteristics of the mammal in need f, which amount may be routinely determined by those skilled in the art.

It will be appreciated that the actual dosages of the SARS-CoVinhibiting agents used in the pharmaceutical compositions of this invention will be selected according to the properties of the particular agent being used, the particular composition formulated, the mode of administration and the particular site, and the host and condition being treated. Optimal dosages for a given set of ions can be ascertained by those skilled in the art using conventional dosage-determination tests.

For oral administration, e.g., a dose that may be employed is from about 0.01 to about 1000 mg/kg body weight, preferably from about 0.1 to about 500 mg/kg body weight, and even more preferably from about 1 to about 500 mg/kg body weight, with courses of treatment ed at appropriate intervals. For intravenous dosing a dose of up to 5 grams per day may be employed. Intravenous administration can occur for intermittent periods during a day or continuously over a 24-hour period.

The terms “cytochrome P450-inhibiting amount” and “cytochrome P450 enzyme activity-inhibiting amount”, as used herein, refer to an amount of a compound required to decrease the activity of cytochrome P450 enzymes or a particular cytochrome P450 enzyme m in the presence of such compound. Whether a particular compound decreases cytochrome P450 enzyme ty, and the amount of such a compound required to do so, can be determined by methods know to those of ordinary skill in the art and the methods described herein.

Protein functions required for coronavirus replication and ription are encoded by the so-called “replicase” gene. Two overlapping polyproteins are translated from this gene and extensively processed by viral proteases. The C-proximal region is processed at eleven conserved interdomain junctions by the virus main or “3C- like” protease. The name “3C-like” protease derives from certain rities between the coronavirus enzyme and the well-known picornavirus 3C proteases. These include ate preferences, use of cysteine as an active site phile in catalysis, and similarities in their ve overall polypeptide folds. A comparison of the amino acid sequence of the SARS-CoVassociated coronavirus e protease to that of other known coronaviruses such as SARS-CoV shows the amino acid sequences have approximately 96% shared homology.

Amino acids of the substrate in the protease cleavage site are numbered from the N to the C terminus as follows: -P1-P1’-P2’-P3’, with cleavage occurring between the P1 and P1’ residues (Schechter & Berger, 1967). Substrate specificity is largely determined by the P2, P1 and P1’ positions. Coronavirus main protease cleavage site specificities are highly conserved with a requirement for glutamine at P1 and a small amino acid at P1’ [Journal of General Virology, 83, pp. 9 (2002)].

The compounds of the present invention can be prepared according to the methods set forth in Reaction Schemes 1 to 3 below.

The schemes ed below further illustrate and exemplify the compounds of the present invention and methods of preparing such compounds. It is to be understood that the scope of the present invention is not limited in any way by the scope of the following examples and preparations. In the following examples molecules with a single chiral center may exist as a single enantiomer or a racemic mixture. Those molecules with two or more chiral centers may exist as a single enantiomer, a racemic or otherwise mixture of two enantiomers, or as various mixtures of diastereomers. Such enantiomers, racemates, and diastereomers may be obtained and / or separated by methods known to those skilled in the art. It will be appreciated by one skilled in the art that certain synthetic manipulations may epimerize or racemize a stereocenter, and synthetic conditions may be selected to either promote or discourage such epimerization or zation.

Scheme 1 illustrates a synthetic sequence for the preparation of nds of Formula I as shown, wherein the N-BOC methyl ester of a 1 ( is converted to a primary amide of a 3 (N-BOC being -butoxycarbonyl).

This may be lished ly, for example by treatment with ammonia (NH3) in a sealed vessel in a solvent such as ol or ethanol, for example, optionally in the presence of additives such as calcium chloride (CaCl2) or magnesium dimethoxide, Mg(OMe)2.

Scheme 1 The transformation of the compound of a 1 to the compound of Formula 3 may also be carried out by prior conversion to the carboxylic acid of Formula 2 (WO 2005/113580). In this case the compound of Formula 2 may be converted to the compound of Formula 3 using methods well known to those skilled in the art. For example, the compound of Formula 2 may be treated with a reagent such as O-(7- azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU), isobutyl chloroformate, 1-[3-(dimethylamino)propyl]ethylcarbodiimide hydrochloride (EDCI) and ybenzotriazole (HOBt), or 1,1’-carbonyldiimidazole (CDI), optionally in the presence of a base such as N,N-diisopropylethylamine (DIEA), 4- methylmorpholine (NMM), or triethylamine (TEA), followed by treatment with NH3 administered as a gas or a solution in a reaction compatible solvent, or with a salt of NH3 such as ammonium e or ammonium chloride in the presence of a base such as N,N-diisopropylethylamine, 4-methylmorpholine, or triethylamine. Suitable solvents include, but are not limited to, dichloromethane (CH2Cl2), N,N-dimethylformamide (DMF), tetrahydrofuran (THF), or acetonitrile (CH3CN).

The compound of Formula 3 may be otected to e an amine of Formula 4 using methods well known to those skilled in the art for effecting such deprotections. Frequently acidic reagents such as hydrogen de, methanesulfonic acid, or trifluoroacetic acid are used, typically in a reaction compatible solvent such as CH2Cl2, 1,4-dioxane, 1,2-dichloroethane, or CH3CN. One skilled in the art will appreciate that the compound of Formula 4 will frequently be obtained as an acid addition salt. The compound of Formula 4 may then be transformed into a compound of Formula 6 by ent with an ected amino acid compound of Formula 5 under appropriate conditions. Such methods are well known to those d in the art, and in general rd peptide coupling conditions may be selected.

The compound of Formula 6 may be N-deprotected to provide an amine of Formula 7 using methods well known to those skilled in the art for effecting such deprotections. Frequently acidic reagents such as hydrogen chloride, methanesulfonic acid, or trifluoroacetic acid are used, typically in a reaction ible solvent such as CH2Cl2, 1,4-dioxane, 1,2-dichloroethane, or CH3CN. One skilled in the art will appreciate that the compound of Formula 7 will frequently be obtained as an acid addition salt. The compound of Formula 7 may then be transformed into a compound of Formula 9 by treatment with a carboxylic acid compound of Formula 8 under appropriate conditions.

Such methods are well known to those d in the art. For example, when X = a ne atom, the carboxylic acid compound is known as an acid chloride and the reaction is conducted in the presence of a base to consume the hydrogen halide HX produced as a by-product of the on. Examples of suitable bases include, but are not d to, tertiary amines such as ylmorpholine, 2,6-dimethylpyridine, or N,N- diisopropylethylamine, or inorganic bases such as magnesium oxide (MgO), sodium carbonate (Na2CO3), or potassium onate (KHCO3). Suitable solvents include, but are not limited to, CH2Cl2, DMF, THF, or CH3CN. When X = OH, it is customary to use a reagent or combination of reagents to facilitate the reaction of the ylic acid compound of Formula 8. One skilled in the art may choose to use, for example, a carbodiimide reagent such as 1-[3-(dimethylamino)propyl]ethylcarbodiimide hydrochloride (EDCI) or N,N’-dicyclohexyl carbodiimide (DCC), optionally in the presence of an auxiliary nucleophile such as hydroxybenzotriazole (HOBt) or oxypyridine-N- oxide (HOPO). Further, when X = OH, one skilled in the art may choose to use reagents that are suitable for the formation of mixed carboxyl / carbonic anhydrides, such as CDI, isobutyl or ethyl chloroformate, ntly in the presence of a base such as described above. Suitable solvents include, but are not limited to, CH2Cl2, THF, or CH3CN. Another approach commonly used by those skilled in the art when X = OH is to treat the carboxylic acid compound of Formula 8 with a carboxylic acid chloride, for example such as Me3CCOCl, in the ce of a base such as described above to generate a mixed carboxylic anhydride of the Formula R3C(O)O(O)CCMe3. Suitable solvents include, but are not limited to, CH2Cl2, THF, or CH3CN. In many cases it is possible to use a symmetric anhydride of the desired carboxylic acid compound of Formula 8 to effect the reaction, optionally in the presence of a base such as described above, in which case X = O(O)CR3 and the carboxylic acid compound of Formula 8 is therefore O(O)CR3. Suitable solvents include, but are not limited to, CH2Cl2, THF, or CH3CN.

The compound of Formula 9 may be transformed into the compound of Formula I by ent under dehydrating conditions well known to those skilled in the art.

Frequently this dehydration step may be accomplished using an excess of trifluoroacetic ide or phosphorus oxychloride, generally in the presence of a base such as pyridine, N,N-diisopropylethylamine, 4-methylmorpholine, or triethylamine.

One skilled in the art will know that the N-BOC protected amino acids of Formula are known in the chemical literature, are commercially available, and may be prepared from the corresponding known and commercially available amino acids by one skilled in the art using well established ures for the sis of N-protected amino acids.

Likewise, one skilled in the art will understand that the carboxylic acid compounds of Formula 8 may be known in the chemical literature, and / or are commercially available, and / or may be prepared by published methods or by analogy to hed methods.

One skilled in the art will iate that the bond-forming steps in Scheme 1 may be conducted in a different order with appropriate erations, for example as shown in Scheme 2.

Scheme 2 In Scheme 2, the compound of Formula 3 is converted into the compound of Formula 10 by treatment under dehydrating conditions well known to those skilled in the art. Frequently this dehydration step may be lished using an excess of trifluoroacetic anhydride or phosphorus oxychloride, generally in the ce of a base such as pyridine, N,N-diisopropylethylamine, 4-methylmorpholine, or triethylamine. The compound of Formula 10 is N-deprotected to provide an amine of Formula 11 using methods well known to those skilled in the art for effecting such ections.

Frequently, acidic reagents such as hydrogen chloride, methanesulfonic acid, or trifluoroacetic acid are used, typically in a reaction-compatible solvent such as CH2Cl2, oxane, 1,2-dichloroethane, or CH3CN. One skilled in the art will appreciate that the compound of Formula 11 will frequently be obtained as an acid addition salt. The compound of Formula 11 may then be transformed into a compound of Formula I by treatment with a compound of Formula 12 under appropriate ions. Such methods are well known to those skilled in the art, and in general standard peptide coupling conditions may be selected. Compounds of Formula 12 are exceptionally well known in the chemical literature, and one skilled in the art may choose to prepare any given compound of Formula 12 using methods analogous to those described in the al literature.

One skilled in the art will appreciate that the bond-forming steps in s 1 and 2 may be conducted in still further ent orders with appropriate considerations, for example as shown in Scheme 3.

Scheme 3 In Scheme 3, the compound of Formula 4 may then be transformed into a compound of Formula 9 by treatment with a compound of Formula 12 under appropriate conditions. Such methods are well known to those skilled in the art, and in general standard e coupling ions may be ed. Compounds of Formula 12 are exceptionally well known in the chemical literature, and one skilled in the art may choose to prepare any given compound of Formula 12 using methods analogous to those described in the chemical literature. The compound of Formula 9 is then converted into the compound of Formula I by treatment under dehydrating conditions well known to those skilled in the art. Frequently this dehydration step may be accomplished using an excess of trifluoroacetic anhydride or phosphorus oxychloride, generally in the presence of a base such as pyridine, N,N-diisopropylethylamine, 4-methylmorpholine, or triethylamine.

One skilled in the art will recognize that still further permutations of the bondforming steps and functional group manipulations in Schemes 1, 2 and 3 may be d with appropriate considerations. Such ations in the selection of step order are well known in the chemical ture and one skilled in the art may consult the chemical literature for further guidance if d. One skilled in the art will recognize that other ions of protecting groups and reagents for effecting the various transformations may be made.

EXAMPLES Experimental Procedures The ing illustrate the synthesis of various compounds of the t invention. Additional compounds within the scope of this invention may be prepared using the s rated in these Examples, either alone or in combination with techniques generally known in the art. All starting materials in these Preparations and Examples are either commercially available or can be ed by methods known in the art or as described herein.

All reactions were carried out using uous stirring under an atmosphere of nitrogen or argon gas unless otherwise noted. When appropriate, reaction apparatuses were dried under dynamic vacuum using a heat gun, and anhydrous solvents (Sure- SealTM products from Aldrich Chemical Company, Milwaukee, Wisconsin or DriSolvTM products from EMD Chemicals, Gibbstown, NJ) were employed. In some cases, commercial solvents were passed through columns packed with 4Å molecular sieves, until the following QC standards for water were attained: a) <100 ppm for dichloromethane, toluene, N,N-dimethylformamide, and tetrahydrofuran; b) <180 ppm for methanol, ethanol, 1,4-dioxane, and diisopropylamine. For very sensitive reactions, solvents were further d with metallic sodium, calcium hydride, or molecular sieves, and distilled just prior to use. Other commercial solvents and reagents were used without further cation. For syntheses ncing procedures in other Examples or Methods, reaction conditions (reaction time and temperature) may vary. Products were generally dried under vacuum before being carried on to further reactions or submitted for biological g.

When indicated, reactions were heated by microwave irradiation using e Initiator or Personal Chemistry Emrys Optimizer microwaves. Reaction progress was monitored using thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LCMS), high-performance liquid tography (HPLC), and/or gas tography-mass spectrometry (GCMS) analyses. TLC was performed on precoated silica gel plates with a fluorescence indicator (254 nm excitation wavelength) and visualized under UV light and/or with I2, KMnO4, CoCl2, phosphomolybdic acid, and/or ceric ammonium ate . LCMS data were acquired on an Agilent 1100 Series instrument with a Leap Technologies autosampler, Gemini C18 columns, acetonitrile/water gradients, and either trifluoroacetic acid, formic acid, or ammonium hydroxide modifiers. The column eluate was analyzed using a Waters ZQ mass spectrometer scanning in both positive and negative ion modes from 100 to 1200 Da.

Other similar instruments were also used. HPLC data were generally acquired on an Agilent 1100 Series instrument, using the columns indicated, acetonitrile/water nts, and either trifluoroacetic acid or ammonium hydroxide modifiers. GCMS data were acquired using a Hewlett Packard 6890 oven with an HP 6890 injector, HP-1 column (12 m x 0.2 mm x 0.33 µm), and helium carrier gas. The sample was analyzed on an HP 5973 mass selective detector scanning from 50 to 550 Da using electron ionization. Purifications were performed by medium mance liquid chromatography (MPLC) using Isco CombiFlash Companion, AnaLogix iFlash 280, Biotage SP1, or Biotage Isolera One instruments and pre-packed Isco RediSep or Biotage Snap silica cartridges. Chiral purifications were performed by chiral supercritical fluid chromatography (SFC), generally using Berger or Thar instruments; columns such as ChiralPAK-AD, -AS, -IC, Chiralcel-OD, or -OJ columns; and CO2 mixtures with methanol, ethanol, 2-propanol, or acetonitrile, alone or modified using trifluoroacetic acid or amine. UV detection was used to trigger fraction collection. For syntheses referencing procedures in other Examples or Methods, purifications may vary: in l, solvents and the t ratios used for eluents/gradients were chosen to provide appropriate Rfs or retention times.

Mass spectrometry data are reported from LCMS analyses. Mass spectrometry (MS) was performed via atmospheric pressure chemical ionization (APCI), ospray ionization (ESI), electron impact ionization (EI) or electron scatter ionization (ES) s. Proton nuclear magnetic spectroscopy (1H NMR) chemical shifts are given in parts per million downfield from tetramethylsilane and were recorded on 300, 400, 500, or 600 MHz Varian, Bruker, or Jeol spectrometers. Chemical shifts are expressed in parts per million (ppm, ) referenced to the deuterated solvent residual peaks (chloroform, 7.26 ppm; CD2HOD, 3.31 ppm; itrile-d2, 1.94 ppm; dimethyl ide-d5, 2.50 ppm; DHO, 4.79 ppm). The peak shapes are described as s: s, singlet; d, t; t, triplet; q, quartet; quin, quintet; m, let; br s, broad singlet; app, apparent. Analytical SFC data were generally acquired on a Berger analytical instrument as described above. Optical rotation data were acquired on a PerkinElmer model 343 polarimeter using a 1 dm cell. nalyses were performed by Quantitative Technologies Inc. and were within 0.4% of the calculated values.

Unless otherwise noted, chemical reactions were performed at room temperature (about 23 degrees Celsius).

Unless noted otherwise, all reactants were obtained commercially and used without further purification, or were prepared using s known in the literature.

The terms “concentrated”, “evaporated”, and “concentrated in vacuo” refer to the removal of solvent at reduced pressure on a rotary evaporator with a bath temperature less than 60 °C. The abbreviations “min” and “h” stand for “minutes” and “hours,” respectively. The term “TLC” refers to thin-layer tography, “room temperature or ambient temperature” means a temperature between 18 to 25 °C, “GCMS” refers to gas tography–mass spectrometry, “LCMS” refers to liquid tography–mass spectrometry, “UPLC” refers to ultra-performance liquid tography, “HPLC” refers to high-performance liquid chromatography, and “SFC” refers to supercritical fluid chromatography.

Hydrogenation may be performed in a Parr shaker under pressurized hydrogen gas, or in a -nano H-Cube flow hydrogenation apparatus at full hydrogen and a flow rate between 1–2 mL/min at specified temperature.

HPLC, UPLC, LCMS, GCMS, and SFC retention times were measured using the methods noted in the procedures.

In some examples, chiral separations were carried out to separate omers or diastereomers of certain compounds of the invention (in some examples, the separated enantiomers are designated as ENT-1 and ENT-2, according to their order of elution; similarly, separated diastereomers are designated as DIAST-1 and DIAST-2, according to their order of elution). In some es, the optical rotation of an enantiomer was measured using a polarimeter. According to its observed rotation data (or its specific rotation data), an enantiomer with a ise rotation was designated as the (+)-enantiomer and an omer with a counter-clockwise rotation was designated as the (-)-enantiomer. Racemic compounds are indicated either by the absence of drawn or described stereochemistry, or by the presence of (+/-) adjacent to the structure; in this latter case, the indicated stereochemistry ents just one of the two enantiomers that make up the racemic mixture.

The compounds and ediates described below were named using the naming tion provided with ACD/ChemSketch 2019.1.1, File Version C05H41, Build 110712 (Advanced Chemistry Development, Inc., Toronto, Ontario, Canada). The naming convention provided with ACD/ChemSketch 2019.1.1 is well known by those skilled in the art and it is believed that the naming convention provided with ACD/ChemSketch 2019.1.1 lly comports with the IUPAC (International Union for Pure and Applied try) recommendations on Nomenclature of Organic Chemistry and the CAS Index rules.

Example 1 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1) Step 1. Synthesis of methyl ,5S)[N-(tert-butoxycarbonyl)-L-valyl]-6,6-dimethyl- icyclo[3.1.0]hexanecarboxylate (C1).

A 0 °C solution of N-(tert-butoxycarbonyl)-L-valine (69.7 g, 321 mmol) in a mixture of itrile and methylformamide (10:1, 1.10 L) was treated with O-(7- azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 122 g, 321 mmol), followed by N,N-diisopropylethylamine (127 mL, 729 mmol). After the reaction mixture had been stirred for 5 minutes, methyl (1R,2S,5S)-6,6-dimethyl yclo[3.1.0]hexanecarboxylate, hydrochloride salt (60.0 g, 292 mmol) was added, and stirring was continued at 0 °C for 1 hour. The reaction mixture was then diluted with aqueous citric acid solution (1 N; 50 mL) and water (100 mL), stirred for 2 minutes, and concentrated in vacuo to approximately one-half of the initial volume. The resulting mixture was partitioned between ethyl acetate and water, and the aqueous layer was extracted three times with ethyl acetate. The combined organic layers were then washed three times with water and once with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was stirred in a l amount of ethyl e, and then filtered; the insoluble material was washed with ethyl acetate until it was white. The combined filtrates were concentrated under reduced pressure and then subjected to silica gel chromatography (Eluent: 1:1 ethyl acetate / heptane), affording C1 as a yellow oil. Yield: 109 g, quantitative. LCMS m/z 369.3 [M+H]+. 1H NMR (400 MHz, chloroform-d)  5.08 (d, J = 9.6 Hz, 1H), 4.45 (s, 1H), 4.11 (dd, J = 9.7, 7.8 Hz, 1H), 3.95 (d, half of AB quartet, J = .1 Hz, 1H), 3.86 (dd, component of ABX system, J = 10.2, 4.8 Hz, 1H), 3.74 (s, 3H), 2.04 – 1.93 (m, 1H), 1.50 – 1.41 (m, 2H), 1.40 (s, 9H), 1.04 (s, 3H), 1.00 (d, J = 6.8 Hz, 3H), 0.95 (d, J = 6.8 Hz, 3H), 0.93 (s, 3H).

Step 2. Synthesis of methyl (1R,2S,5S)-6,6-dimethylL-valyl yclo[3.1.0]hexanecarboxylate, hydrochloride salt (C2).

A solution of hydrogen chloride in 1,4-dioxane (4 M; 15 mL, 60 mmol) was added to a 0 °C solution of C1 (1.00 g, 2.71 mmol) in ethyl acetate (50 mL). The reaction mixture was stirred at 0 °C for 2 hours, whereupon additional hydrogen chloride in 1,4- dioxane solution (4 M; 10 mL, 40 mmol) was added, and stirring was continued at 0 °C for 3 hours, then at room ature for 1 hour. The reaction mixture was then treated with a solution of hydrogen chloride in 1,4-dioxane (4 M; 10 mL, 40 mmol) and ol (15 mL) and allowed to stir overnight at room temperature. Concentration in vacuo afforded C2 as a gum; this material was used in further chemistry without additional purification, and the reaction was assumed to be quantitative. LCMS m/z 269.3 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  8.24 (br s, 3H), 4.27 (s, 1H), 3.81 – 3.61 (m, 3H), 3.67 (s, 3H), 2.21 – 2.06 (m, 1H), 1.63 – 1.55 (m, 1H), 1.49 (d, component of AB quartet, J = 7.6 Hz, 1H), 1.09 – 0.88 (m, 12H).

Step 3. Synthesis of methyl (1R,2S,5S)-6,6-dimethyl[N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxylate (C3).

Triethylamine (1.55 mL, 11.1 mmol) was added to a 0 °C solution of C2 (1.0 g, 3.3 mmol) in dichloromethane (37 mL), followed by drop-wise addition of trifluoroacetic anhydride (0.57 mL, 4.0 mmol) over 30 minutes. The reaction mixture was stirred at 0 °C for 30 minutes, whereupon it was d with dichloromethane (100 mL), washed sequentially with 10% aqueous potassium bisulfate solution (50 mL) and saturated aqueous sodium chloride on (30 mL), dried over sodium e, ed, and concentrated in vacuo to provide C3 as a light-yellow oil. Yield: 1.2 g, 3.3 mmol, quantitative. LCMS m/z 365.2 [M+H]+. 1H NMR (400 MHz, chloroform-d)  7.04 (br d, J = 8.8 Hz, 1H), 4.54 (dd, J = 8.9, 6.3 Hz, 1H), 4.46 (s, 1H), 3.91 (dd, J = 10.1, 5.0 Hz, 1H), 3.80 – 3.73 (m, 1H), 3.76 (s, 3H), 2.25 – 2.13 (m, 1H), 1.55 – 1.47 (m, 2H), 1.09 – 1.03 (m, 6H), 0.94 (d, J = 6.8 Hz, 3H), 0.92 (s, 3H).

Step 4. Synthesis of (1R,2S,5S)-6,6-dimethyl[N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxylic acid (C4).

Concentrated hydrochloric acid (0.57 mL, 6.6 mmol) was added to a on of C3 (1.25 g, 3.43 mmol) in a e of acetic acid (40.8 mL) and water (8.2 mL). The reaction mixture was heated at 55 °C for 3 days, pon it was partitioned between water (50 mL) and ethyl acetate (100 mL). The aqueous layer was extracted with ethyl acetate (2 x 50 mL), and the combined organic layers were washed with saturated aqueous sodium de solution (50 mL), dried over sodium sulfate, filtered, and concentrated in vacuo to afford C4 as a white foam. Yield: 1.00 g, 2.85 mmol, 83%.

LCMS m/z 351.2 [M+H]+. 1H NMR (400 MHz, chloroform-d), characteristic peaks:  4.56 – 4.44 (m, 2H), 2.24 – 2.12 (m, 1H), [1.66 (d, component of AB quartet, J = 7.5 Hz) and 1.59 – 1.47 (m), total 2H], 1.10 – 1.01 (m, 6H), 0.96 – 0.91 (m, 6H).

Step 5. Synthesis of tert-butyl {(2S)aminooxo[(3S)oxopyrrolidinyl]propan- 2-yl}carbamate (C5).

A solution of ammonia in methanol (7.0 M; 150 mL, 1.0 mol) was added to a 0 °C solution of methyl N-(tert-butoxycarbonyl)[(3S)oxopyrrolidinyl]-L-alaninate (5.00 g, 17.5 mmol) in methanol (25 mL). After the reaction mixture had been stirred at room temperature for 3 days, it was concentrated in vacuo; the residue was diluted and reconcentrated sequentially with a mixture of ethyl acetate and heptane (1:1, 4 x 50 mL) followed by e (50 mL) to provide C5 as a solid (5.27 g, assumed quantitative) that contained residual solvent. A portion of this material was used in the following step.

LCMS m/z 216.2 [(M − 2-methylpropene)+H]+. 1H NMR (400 MHz, methanol-d4)  4.16 – 3.96 (m, 1H), 3.40 – 3.27 (m, 2H, assumed; lly obscured by t peak), 2.55 – 2.42 (m, 1H), 2.35 (dddd, J = 12.2, 8.6, 6.8, 3.3 Hz, 1H), 2.03 (ddd, J = 14.0, 11.0, 4.4 Hz, 1H), 1.93 – 1.81 (m, 1H), 1.74 (ddd, J = 14.2, 10.1, 4.3 Hz, 1H), 1.45 (s, Step 6. Synthesis of tert-butyl {(1S)cyano[(3S)oxopyrrolidin yl]ethyl}carbamate (C6). 2,6-Dimethylpyridine (2 mL, 17 mmol) and trifluoroacetic anhydride (0.94 mL, 6.6 mmol) were added to a 0 °C solution of C5 (from the previous step; 1.0 g, ≤3.3 mmol) in dichloromethane (12 mL). The on mixture was stirred at room temperature for 1.5 hours, whereupon it was treated with hydrochloric acid (1 M; 30 mL) and dichloromethane (60 mL). The organic layer was washed sequentially with saturated aqueous sodium de solution (30 mL) and saturated aqueous sodium bicarbonate solution (30 mL), dried over sodium sulfate, and concentrated in vacuo; chromatography on silica gel (Gradient: 40% to 100% ethyl acetate in heptane) afforded C6 as a solid. Yield: 737 mg, 2.91 mmol, 88% over 2 steps. LCMS m/z 254.3 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  4.72 (dd, J = 9.3, 6.8 Hz, 1H), 3.39 – 3.27 (m, 2H, assumed; partially obscured by solvent peak), 2.57 – 2.46 (m, 1H), 2.36 (dddd, J = 12.2, 8.6, 6.3, 3.4 Hz, 1H), 2.21 (ddd, J = 13.8, 9.3, 5.6 Hz, 1H), 1.92 – 1.79 (m, 2H), 1.47 (s, 9H).

Step 7. Synthesis of (2S)amino[(3S)oxopyrrolidinyl]propanenitrile, methanesulfonate salt (C7).

To a on of C6 (317 mg, 1.25 mmol) in 1,1,1,3,3,3-hexafluoropropanol (3 mL) was added methanesulfonic acid (81.2 µL, 1.25 mmol). After the reaction e had been stirred at room temperature for 45 minutes, it was concentrated in vacuo, then repeatedly taken up in a mixture of solvents and reconcentrated: acetonitrile and ethyl acetate (1:1, 2 x 10 mL) followed by ethyl acetate and heptane (1:1, 2 x 10 mL). The resulting C7 was obtained as a glass (423 mg), which was free of the e epimer via 1H and 13C NMR analysis. A portion of this material was used in further ons without additional purification. LCMS m/z 154.2 [M+H]+. 1H NMR (400 MHz, methanol- d4)  4.78 (t, J = 7.3 Hz, 1H), 3.42 – 3.36 (m, 2H), 2.82 – 2.68 (m, 1H), 2.70 (s, 3H), 2.50 – 2.39 (m, 1H), 2.20 (t, J = 7.3 Hz, 1H), 2.07 – 1.80 (m, 2H).

Step 8. Synthesis of (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- dimethyl[N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1).

A e of C7 (from the previous step; 98.8 mg, ≤0.292 mmol) and C4 (100 mg, 0.285 mmol) in acetonitrile (1.5 mL) was cooled to 0 °C. O-(7-Azabenzotriazol yl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU, 97%; 112 mg, 0.286 mmol) was added, followed by a solution of 4-methylmorpholine (94.0 µL, 0.855 mmol) in acetonitrile (0.5 mL), and the reaction mixture was stirred at 0 °C for approximately 2 hours. Saturated aqueous sodium bicarbonate solution (30 mL) was then added to the 0 °C on mixture, followed by dichloromethane (50 mL), and the organic layer was washed with hydrochloric acid (1 M; 30 mL). The combined aqueous layers were extracted with dichloromethane (60 mL), whereupon the ed organic layers were dried over sodium e, concentrated in vacuo, and subjected to silica gel chromatography (Gradient: 0% to 20% methanol in ethyl acetate). As the resulting material was judged by NMR and LCMS to be contaminated with an epimer of the product, it was then purified via reversed-phase HPLC (Column: Waters Sunfire C18, 19 x 100 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v); Gradient: 5% to 95% B over 8.54 minutes, then 95% B for 1.46 s; Flow rate: 25 mL/minute) to afford (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1). Yield: 14.6 mg, .1 µmol, 11%. LCMS m/z 486.5 [M+H]+. Retention time: 2.33 minutes (Analytical conditions. Column: Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: itrile containing 0.05% trifluoroacetic acid (v/v). Gradient: 5% to 95% B over 4.0 s, then 95% B for 1.0 minute. Flow rate: 2 mL/minute).

Alternate sis of C4 (1R,2S,5S)-6,6-Dimethyl[N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxylic acid (C4) Step 1. Synthesis of (1R,2S,5S)[N-(tert-butoxycarbonyl)-L-valyl]-6,6-dimethyl azabicyclo[3.1.0]hexanecarboxylic acid (C8).

An aqueous on of lithium hydroxide (2.0 M; 436 mL, 872 mmol) was added to a solution of C1 (107 g, 290 mmol) in tetrahydrofuran (730 mL). After the resulting mixture had been stirred at room ature for approximately 2 hours, it was diluted with water and ethyl e, then treated with 1 M aqueous sodium hydroxide solution. The aqueous layer was washed with ethyl e, and the combined organic layers were extracted three times with 1 M aqueous sodium ide solution, until LCMS analysis indicated that C8 had been completely removed from the organic layer. Acidification of the ed aqueous layers to pH 2 was carried out by addition of concentrated hydrochloric acid, whereupon the mixture was extracted three times with ethyl acetate.

The combined organic layers were washed with saturated aqueous sodium de solution, dried over sodium sulfate, filtered, and concentrated; trituration of the residue with heptane afforded C8 as a white solid. Yield: 92.8 g, 262 mmol, 90%. LCMS m/z 355.3 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  4.32 (s, 1H), 4.05 (d, half of AB quartet, J = 10.5 Hz, 1H), 4.01 (d, J = 9.0 Hz, 1H), 3.88 (dd, component of ABX system, J = 10.4, 5.3 Hz, 1H), 2.03 – 1.91 (m, 1H), 1.57 (dd, component of ABX system, J = 7.5, .2 Hz, 1H), 1.50 (d, half of AB quartet, J = 7.5 Hz, 1H), 1.41 (s, 9H), 1.08 (s, 3H), 0.99 (d, J = 6.8 Hz, 3H), 0.97 – 0.94 (m, 6H).

Step 2. Synthesis of (1R,2S,5S)-6,6-dimethylL-valylazabicyclo[3.1.0]hexane carboxylic acid, hydrochloride salt (C9).

To a solution of C8 (82.8 g, 234 mmol) in dichloromethane (230 mL) was added a solution of hydrogen chloride in 1,4-dioxane (4.0 M; 409 mL, 1.64 mol). The reaction mixture was stirred overnight at room ature, whereupon it was concentrated in vacuo, providing C9 as a white foam. This material was used directly in the following step. LCMS m/z 255.3 [M+H]+. 1H NMR (400 MHz, ol-d 4)  4.42 (s, 1H), 4.05 (d, J = 4.8 Hz, 1H), 3.89 (dd, component of ABX system, J = 10.5, 5.2 Hz, 1H), 3.74 (d, half of AB quartet, J = 10.5 Hz, 1H), 2.36 – 2.25 (m, 1H), 1.62 (dd, component of ABX system, J = 7.5, 5.1 Hz, 1H), 1.57 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.16 (d, J = 7.0 Hz, 3H), 1.10 (s, 3H), 1.04 (d, J = 6.9 Hz, 3H), 1.01 (s, 3H).

Step 3. Synthesis of (1R,2S,5S)-6,6-dimethyl[N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxylic acid (C4).

A solution of C9 (from the previous step; ≤234 mmol) in ol (230 mL) was cooled to 0 °C, treated with triethylamine (66.7 mL, 479 mmol), and stirred for 5 minutes, whereupon ethyl trifluoroacetate (36.1 mL, 303 mmol) was slowly added. After the reaction mixture had been allowed to stir at room temperature for 90 minutes, it was concentrated in vacuo. The residue was diluted with water, 1 M aqueous sodium hydroxide solution, and ethyl acetate, and the resulting organic layer was extracted twice with 1 M aqueous sodium hydroxide solution. The combined aqueous layers were acidified to pH 2 by addition of 1 M hydrochloric acid, then extracted three times with ethyl acetate. The combined organic layers were washed with water and with ted aqueous sodium chloride solution, dried over sodium sulfate, ed, and trated in vacuo, affording C4 as a white foam. Yield: 73.4 g, 210 mmol, 90% over 2 steps.

LCMS m/z 351.3 [M+H]+. 1H NMR (400 MHz, DMSO-d6)  12.65 (v br s, 1H), 9.82 (d, J = 7.7 Hz, 1H), 4.16 (dd, J = 9.9, 7.9 Hz, 1H), 4.12 (s, 1H), 3.86 (d, half of AB quartet, J = 10.4 Hz, 1H), 3.81 (dd, component of ABX system, J = 10.5, 5.0 Hz, 1H), 2.18 – 2.05 (m, 1H), 1.54 (dd, component of ABX system, J = 7.7, 4.6 Hz, 1H), 1.42 (d, half of AB quartet, J = 7.5 Hz, 1H), 1.02 (s, 3H), 0.95 (d, J = 6.7 Hz, 3H), 0.89 (d, J = 6.6 Hz, 3H), 0.84 (s, 3H).

Alternate Synthesis of Example 1 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1) Step 1. Synthesis of methyl 3-[(3S)oxopyrrolidinyl]-L-alaninate, methanesulfonate salt (C10).

To a solution of methyl t-butoxycarbonyl)[(3S)oxopyrrolidinyl]-L- alaninate (10.1 g, 35.3 mmol) in 1,1,1,3,3,3-hexafluoropropanol (70 mL) was added methanesulfonic acid (2.30 mL, 35.4 mmol). After the reaction mixture had been stirred at room temperature for 70 minutes, LCMS analysis indicated that the starting material had been converted to C10: LCMS m/z 187.2 [M+H]+. The reaction mixture was concentrated in vacuo, and the residue was redissolved twice, followed by concentration under reduced pressure, in a mixture of acetonitrile and ethyl acetate (1:1, 2 x 20 mL). The resulting material was taken up in a mixture of acetonitrile and ethyl e (1:1, 30 mL), trated, then twice redissolved in ethyl acetate (2 x 40 mL) and concentrated. The residue was triturated with ethyl e (60 mL) to afford C10. Yield: 9.87 g, 35.0 mmol, 99%. 1H NMR (400 MHz, methanol-d 4)  4.22 (dd, J = 9.7, 3.6 Hz, 1H), 3.86 (s, 3H), 3.41 – 3.36 (m, 2H), 2.84 – 2.74 (m, 1H), 2.70 (s, 3H), 2.41 (dddd, J = 12.3, 8.6, 5.1, 3.6 Hz, 1H), 2.25 (ddd, J = 15.1, 4.5, 3.6 Hz, 1H), 1.98 (ddd, J = 15.1, 9.6, 9.6 Hz, 1H), 1.87 (dddd, J = 12.6, 10.9, 9.2, 9.2 Hz, 1H).

Step 2. Synthesis of methyl R,2S,5S)-6,6-dimethyl[N-(trifluoroacetyl)-L-valyl] yclo[3.1.0]hexanyl}carbonyl)[(3S)oxopyrrolidinyl]-L-alaninate (C11).

To a 0 °C solution of C10 (2.76 g, 9.78 mmol) and C4 (3.43 g, 9.79 mmol) in acetonitrile (40 mL) was added 1-[3-(dimethylamino)propyl]ethylcarbodiimide hydrochloride (1.88 g, 9.81 mmol), followed by drop-wise addition of pyridine (2.37 mL, 29.3 mmol). The reaction mixture was d at 0 °C for 2.25 hours, whereupon it was treated with hydrochloric acid (1 M; 50 mL) and extracted with ethyl acetate (150 mL).

The organic layer was washed sequentially with saturated s sodium chloride solution (50 mL), saturated aqueous sodium onate solution (50 mL), and saturated s sodium chloride solution (50 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was taken up in methyl tert-butyl ether (30 mL) and concentrated under reduced pressure, and the ing glass was stirred with methyl tert-butyl ether (50 mL) at room temperature overnight. After filtration, the filter cake was washed with methyl tert-butyl ether (3 x 6 mL) to afford C11 as a solid, which by 1H NMR analysis contained substantial residual methyl tert-butyl ether. A portion of this material was used in the following step. Yield: 3.74 g; ted for residual methyl tert-butyl ether: 2.94 g, 5.67 mmol, 58%. LCMS m/z 519.5 [M+H]+. 1H NMR (400 MHz, methanol-d4)  4.55 (dd, J = 12.0, 3.8 Hz, 1H), 4.34 (s, 1H), 4.29 (d, J = 9.6 Hz, 1H), 3.97 (d, J = 3.1 Hz, 2H), 3.74 (s, 3H), 3.37 – 3.23 (m, 2H, d; partially obscured by solvent peak), 2.73 – 2.62 (m, 1H), 2.32 (dddd, J = 12.4, 8.8, 6.7, 2.4 Hz, 1H), 2.21 – 2.10 (m, 2H), 1.86 – 1.74 (m, 2H), 1.60 (dt, component of ABX2 system, J = 7.7, 3.1 Hz, 1H), 1.49 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.09 (s, 3H), 1.02 (d, J = 6.9 Hz, 3H), 0.99 – 0.95 (m, 6H).

Step 3. Synthesis of (1R,2S,5S)-N-{(2S)aminooxo[(3S)oxopyrrolidin yl]propanyl}-6,6-dimethyl[N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide (C12).

A solution of ammonia in methanol (7.0 M; 5 mL, 40 mmol) was added to a solution of C11 (from the previous step: 205 mg, 0.311 mmol) in methanol (1 mL). The resulting solution was stirred at room temperature for 1.5 hours, whereupon a solution of ammonia in methanol (7.0 M; 5 mL, 40 mmol) was again added, and stirring was continued overnight. The reaction mixture was then treated for a third time with the same quantity of ammonia in methanol; after a further 8 hours of reaction, it was concentrated in vacuo. The residue was diluted and entrated sequentially with ethyl acetate (2 x 20 mL) and a mixture of ethyl acetate and heptane (1:1, 2 x 20 mL).

The resulting material was dissolved in dichloromethane (50 mL), washed with hydrochloric acid (1 M; 30 mL) and with saturated aqueous sodium chloride solution (30 mL), dried over sodium e, filtered, and concentrated in vacuo to provide C12 as a solid. Yield: 87 mg, 0.17 mmol, 55%. LCMS m/z 504.5 [M+H]+. 1H NMR (400 MHz, methanol-d4)  8.68 (d, J = 7.9 Hz, <1H, incompletely exchanged with solvent), 4.44 (ddd, J = 11.9, 7.9, 4.0 Hz, 1H), 4.37 – 4.26 (m, 2H), 4.01 (dd, component of ABX system, J = 10.3, 5.1 Hz, 1H), 3.94 (d, half of AB quartet, J = 10.2 Hz, 1H), 3.39 – 3.24 (m, 2H, d; largely obscured by solvent peak), 2.72 – 2.62 (m, 1H), 2.38 – 2.28 (m, 1H), 2.21 – 2.08 (m, 2H), 1.90 – 1.72 (m, 2H), 1.58 (dd, component of ABX system, J = 7.5, 5 Hz, 1H), 1.54 (d, half of AB quartet, J = 7.7 Hz, 1H), 1.08 (s, 3H), 1.02 (d, J = 6.7 Hz, 3H), 0.97 (d, J = 6.7 Hz, 3H), 0.96 (s, 3H).

Step 4. Synthesis of (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- dimethyl[N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1).

Methyl N-(triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 88.4 mg, 0.371 mmol) was added to a on of C12 (85.0 mg, 0.17 mmol) in dichloromethane (4.0 mL), and the reaction mixture was d at room temperature.

After 3 hours, methyl N-(triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 20 mg, 84 µmol) was again added; 30 minutes later, the reaction mixture was diluted with ethyl acetate (60 mL), washed sequentially with hydrochloric acid (1 M; 30 mL), saturated aqueous sodium bicarbonate solution (30 mL), and saturated aqueous sodium chloride solution (30 mL), dried over sodium e, filtered, and concentrated in vacuo. The e was taken up in e and reconcentrated before being purified via silica gel chromatography (Gradient: 0% to 5% methanol in ethyl acetate). ,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[N- (trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (1) was isolated as a solid. Yield: 35 mg, 72 µmol, 42%. LCMS m/z 486.5 [M+H]+. 1H NMR (400 MHz, methanol-d4)  5.04 (dd, J = 10.7, 5.4 Hz, 1H), 4.28 (d, J = 9.6 Hz, 1H), 4.25 (s, 1H), 4.03 – 3.94 (m, 2H), 3.35 – 3.23 (m, 2H, assumed; largely obscured by solvent peak), 2.72 – 2.62 (m, 1H), 2.37 – 2.26 (m, 2H), 2.19 – 2.08 (m, 1H), 1.93 – 1.75 (m, 2H), 1.64 (ddd, J = 7.6, 4.2, 2.1 Hz, 1H), 1.41 (d, J = 7.6 Hz, 1H), 1.09 (s, 3H), 1.02 (d, J = 6.8 Hz, 3H), 1.00 – 0.95 (m, 6H).

Example 2 N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2-(pyrrolidinylacetyl)-L- leucinamide, trifluoroacetate salt (2) Step 1. Synthesis of benzyl 4-methyl-L-leucinate, p-toluenesulfonic acid salt (C13).

A suspension of 4-methyl-L-leucine (9.5 g, 65 mmol), benzyl alcohol (28.3 g, 262 mmol), and p-toluenesulfonic acid drate (14.9 g, 78.3 mmol) in toluene (200 mL) was heated at reflux overnight; a Dean-Stark trap was employed to azeotropically remove the resulting water. The reaction mixture was then concentrated in vacuo, whereupon the residue was d with diethyl ether (200 mL) and ethyl acetate (100 mL). The resulting suspension was stirred for 1.5 hours and filtered; the filter cake was washed with diethyl ether to provide C13 as a white solid. Yield: 24.9 g, 61.1 mmol, 94%. LCMS m/z 236.3 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  8.30 (br s, 3H), 7.47 (d, J = 8.1 Hz, 2H), 7.44 – 7.36 (m, 5H), 7.11 (d, J = 7.8 Hz, 2H), 5.23 (AB quartet, JAB = 12.3 Hz, ΔAB = 13.7 Hz, 2H), 4.02 (dd, J = 7.3, 4.5 Hz, 1H), 2.29 (s, 3H), 1.81 (dd, J = 14.5, 7.3 Hz, 1H), 1.57 (dd, J = 14.5, 4.6 Hz, 1H), 0.90 (s, 9H).

Step 2. sis of benzyl 4-methyl-N-(pyrrolidinylacetyl)-L-leucinate (C14).

A 0 °C mixture of C13 (800 mg, 1.96 mmol) and pyrrolidinylacetic acid (254 mg, 1.97 mmol) in N,N-dimethylformamide (4 mL) was treated with O-(7- azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 746 mg, 1.96 mmol), followed by a solution of 4-methylmorpholine (0.496 mL, 4.51 mmol) in dichloromethane (1 mL). After the reaction mixture had been stirred at 0 °C for 2 hours, saturated aqueous sodium bicarbonate solution (30 mL) was added at 0 °C; the ing e was ted with ethyl acetate (2 x 60 mL), and the combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo.

Purification via silica gel chromatography was carried out twice (Gradient: 0% to 20% ethyl acetate in heptane, followed by a second chromatographic purification using 0% to % ethyl acetate in heptane), to afford C14 as a gum (761 mg). This material was used directly in the following step. LCMS m/z 347.4 [M+H]+. 1H NMR (400 MHz, methanol-d4)  7.40 – 7.29 (m, 5H), 5.16 (AB quartet, JAB = 12.2 Hz, ΔAB = 11.1 Hz, 2H), 4.56 (dd, J = 9.0, 3.1 Hz, 1H), 3.76 (AB quartet, JAB = 15.6 Hz, ΔAB = 13.6 Hz, 2H), 3.17 – 3.06 (m, 4H), 2.03 – 1.93 (m, 4H), 1.81 (dd, J = 14.5, 3.1 Hz, 1H), 1.60 (dd, J = 14.5, 9.0 Hz, 1H), 0.95 (s, 9H).

Step 3. Synthesis of 4-methyl-N-(pyrrolidinylacetyl)-L-leucine (C15).

To a solution of C14 (from the previous step; 760 mg, ≤1.96 mmol) in methanol (5 mL) was added palladium on carbon (76.0 mg). The reaction e was stirred at room temperature under en (50 psi) overnight, whereupon LCMS analysis indicated conversion to C15: LCMS m/z 257.4 [M+H]+. The on mixture was filtered twice through a 0.15 µm , and the filtrate was concentrated in vacuo. The residue was twice dissolved in a mixture of ethyl acetate and heptane (1:1, 2 x 20 mL), followed by concentration under reduced pressure; this provided C15 as a solid (646 mg).

Portions of this material were used in subsequent chemistry without further purification. 1H NMR (400 MHz, DMSO-d 6)  8.46 (d, J = 8.3 Hz, 1H), 4.31 (ddd, J = 8.9, 8.6, 3.0 Hz, 1H), 3.74 – 3.60 (m, 2H), 3.00 br (s, 4H), 1.90 – 1.79 (m, 4H), 1.70 (dd, component of ABX system, J = 14.3, 3.0 Hz, 1H), 1.56 (dd, component of ABX system, J = 14.3, 9.2 Hz, 1H), 0.90 (s, 9H).

Step 4. Synthesis of N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-N2- (pyrrolidinylacetyl)-L-leucinamide, trifluoroacetate salt (2).

A mixture of C15 (from the previous step; 30 mg, ≤91 µmol) and C7 (from Step 7 of Example 1; 35.3 mg, ≤0.104 mmol) in N,N-dimethylformamide (1 mL) was cooled to 0 °C and treated with O-(7-azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium uorophosphate (HATU, 97%; 39.9 mg, 0.102 mmol), followed by a solution of 4- methylmorpholine (28.0 µL, 0.255 mmol) in dichloromethane (0.25 mL). After the reaction mixture had been stirred at 0 °C for about 1.5 hours, it was diluted with saturated aqueous sodium bicarbonate solution (3 mL) at 0 °C and extracted with dichloromethane (4 x 4 mL). The combined organic layers were concentrated in vacuo and ed via reversed-phase HPLC (Column: Waters Sunfire C18, 19 x 100 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v); Gradient: 5% to 25% B over 8.5 minutes, then 25% to 95% acetonitrile over 0.5 minutes, then 95% B for 1.0 minute; Flow rate: 25 mL/minute) to afford N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl} methyl-N2-(pyrrolidinylacetyl)-L-leucinamide, trifluoroacetate salt (2) as a gum. Yield: 8.1 mg, 16 µmol, 18% over 3 steps. LCMS m/z 392.6 [M+H]+. ion time: 1.47 minutes (Analytical conditions. : Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% oroacetic acid (v/v); Mobile phase B: acetonitrile ning 0.05% trifluoroacetic acid (v/v). Gradient: 5% to 95% B over 4.0 minutes, then 95% B for 1.0 minute. Flow rate: 2 mL/minute).

Example 3 N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(2,6-dichlorobenzoyl)methyl-L- leucinamide (3) Step 1. Synthesis of 3-[(3S)oxopyrrolidinyl]-L-alaninamide, methanesulfonate salt, (C16).

To a solution of C5 (6.13 g, ≤19 mmol) in 1,1,1,3,3,3-hexafluoropropanol (40 mL) was added methanesulfonic acid (1.83 g, 19 mmol). The reaction mixture was stirred at room ature for 1 hour, pon it was concentrated in vacuo, ended in a mixture of toluene and heptane, and concentrated once more, providing a hygroscopic glass (7.47 g). A portion of this material (6.47 g) was diluted and reconcentrated sequentially with the following: a mixture of dichloromethane and ethanol (2:3, 2 x 50 mL); ethyl acetate and l (2:3, 50 mL); ethyl acetate, heptane, and dichloromethane (4:4:1, 2 x 50 mL). The resulting material was dissolved in a mixture of acetonitrile and water (1:1, 22 mL) and lyophilized for 2 days to afford C16 as a glass. Yield: 3.23 g, 12.1 mmol, 73% over 2 steps. LCMS m/z 172.2 [M+H]+. 1H NMR (400 MHz, methanol-d4)  4.03 (dd, J = 9.1, 4.6 Hz, 1H), 3.43 – 3.35 (m, 2H), 2.82 – 2.72 (m, 1H), 2.71 (s, 3H), 2.49 – 2.38 (m, 1H), 2.12 – 1.96 (m, 2H), 1.94 – 1.81 (m, Step 2. Synthesis of N-(tert-butoxycarbonyl)methyl-L-leucyl[(3S)oxopyrrolidin yl]-L-alaninamide (C17).

A 0 °C on of C16 (1.34 g, 5.02 mmol) and N-(tert-butoxycarbonyl)methyl- L-leucine (1.28 g, 5.22 mmol) in N,N-dimethylformamide (7.0 mL) was treated with O- benzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU, 97%; 2.04 g, 5.20 mmol), followed by a solution of 4-methylmorpholine (1.43 mL, 13.0 mmol) in dichloromethane (3 mL). After the reaction e had been stirred at 0 °C for 2.25 hours, it was quenched at 0 °C by addition of hydrochloric acid (1 M; 30 mL) and then diluted with dichloromethane (50 mL). The organic layer was washed with saturated aqueous sodium bicarbonate solution (30 mL), and the combined aqueous layers were extracted with dichloromethane (60 mL). The combined organic layers were dried over sodium sulfate, filtered, concentrated in vacuo, and suspended / concentrated with heptane (3 x 10 mL). cation of the residue via silica gel chromatography (Gradient: 0% to 20% methanol in ethyl acetate) afforded C17 as a solid. Yield: 1.42 g, 3.56 mmol, 71%. LCMS m/z 399.4 [M+H]+. 1H NMR (400 MHz, methanol-d4)  6.83 (d, J = 7.4 Hz, <1H, incompletely exchanged with solvent), 4.43 (dd, J = 11.2, 4.2 Hz, 1H), 4.11 – 4.05 (m, 1H), 3.38 – 3.24 (m, 2H, assumed; partially obscured by t peak), 2.52 – 2.41 (m, 1H), 2.40 – 2.30 (m, 1H), 2.13 (ddd, J = 14.0, 11.2, 4.5 Hz, 1H), 1.91 – 1.75 (m, 2H), 1.71 (dd, component of ABX system, J = 14.4, 3.2 Hz, 1H), 1.51 (dd, component of ABX system, J = 14.4, 9.3 Hz, 1H), 1.45 (s, 9H), 0.97 (s, 9H).

Step 3. Synthesis of 4-methyl-L-leucyl[(3S)oxopyrrolidinyl]-L-alaninamide, methanesulfonate salt (C18).

Methanesulfonic acid (32.6 µL, 0.502 mmol) was added to a solution of C17 (200 mg, 0.502 mmol) in 1,1,1,3,3,3-hexafluoropropanol (1.5 mL). The reaction mixture was stirred at room temperature for 40 minutes, whereupon it was trated in vacuo, dissolved in ethyl acetate and concentrated once more, providing C18 as a solid (238 mg). Most of this material was used in the following step. LCMS m/z 299.4 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  4.53 (dd, J = 10.3, 5.0 Hz, 1H), 3.91 (dd, J = 7.6, 5.5 Hz, 1H), 3.41 – 3.27 (m, 2H, assumed; partially obscured by solvent peak), 2.70 (s, 3H), 2.57 – 2.47 (m, 1H), 2.41 (dddd, J = 12.0, 8.6, 7.0, 3.2 Hz, 1H), 2.15 (ddd, J = 14.0, .3, 5.0 Hz, 1H), 2.01 (dd, J = 14.4, 7.5 Hz, 1H), 1.96 – 1.85 (m, 1H), 1.78 (ddd, J = 14.1, 9.1, 5.0 Hz, 1H), 1.59 (dd, J = 14.3, 5.5 Hz, 1H), 1.01 (s, 9H).

Step 4. Synthesis of N-(2,6-dichlorobenzoyl)methyl-L-leucyl[(3S)oxopyrrolidin- 3-yl]-L-alaninamide (C19).

A 0 °C suspension of C18 (from the previous step: 234 mg, ≤0.49 mmol) in dichloromethane (2 mL) was treated with ylamine (170 µL, 1.2 mmol) followed by drop-wise addition of a on of 2,6-dichlorobenzoyl chloride (130 mg, 0.621 mmol) in dichloromethane (0.2 mL). The reaction mixture was stirred at room temperature for 1 hour, whereupon it was diluted with dichloromethane (60 mL), then washed with hydrochloric acid (1 M; 30 mL) followed by saturated aqueous sodium bicarbonate solution (30 mL). The organic layer was dried over sodium e, filtered, concentrated in vacuo, and subjected to chromatography on silica gel (Gradient: 0% to 30% methanol in ethyl acetate) to afford C19. Yield: 120 mg, 0.255 mmol, 52% over 2 steps. LCMS m/z 471.4 (dichloro isotope pattern observed) . 1H NMR (400 MHz, methanol-d 4)  8.45 (d, J = 7.9 Hz, <1H, incompletely exchanged with t), 7.45 – 7.35 (m, 3H), 4.59 (dd, J = 7.8, 4.5 Hz, 1H), 4.52 – 4.44 (m, 1H), 3.37 – 3.24 (m, 2H, assumed; partially obscured by solvent peak), 2.65 – 2.55 (m, 1H), 2.37 (dddd, J = 12.5, 8.8, 6.6, 2.8 Hz, 1H), 2.19 (ddd, J = 13.9, 11.3, 4.5 Hz, 1H), 1.91 – 1.72 (m, 3H), 1.66 (dd, component of ABX system, J = 14.4, 7.8 Hz, 1H), 1.03 (s, 9H).

Step 5. Synthesis of N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2-(2,6- dichlorobenzoyl)methyl-L-leucinamide (3).

A solution of C19 (90 mg, 0.19 mmol) and 1H-imidazole (33.8 mg, 0.496 mmol) in pyridine (1 mL) was cooled in an acetonitrile / dry ice bath (−35 °C). To this was added orus oxychloride (0.100 mL, 1.07 mmol), and the reaction e was stirred at −30 °C to −20 °C. After 30 minutes, pyridine (2 mL) was added to tate stirring; after 1 hour, dichloromethane (2 mL) was added for the same reason. At 2 hours of reaction, phosphorus oxychloride (0.100 mL, 1.07 mmol) was again added, and stirring was ued for 30 minutes at −30 °C, whereupon the reaction mixture was warmed to 0 °C and stirred for an additional 40 minutes. It was then treated with hydrochloric acid (1 M; 30 mL) and extracted with dichloromethane (2 x 60 mL). The combined organic layers were dried over sodium sulfate, filtered, concentrated in vacuo, and subjected to silica gel chromatography (Gradient: 0% to 15% methanol in ethyl acetate) to provide a solid (67 mg). This material was ed with the product (12 mg) from a similar reaction carried out using C19 (30 mg, 64 µmol) and twice taken up in ethyl acetate (2 x 3 mL) followed by concentration under reduced pressure. The residue was stirred with a mixture of ethyl acetate and heptane (1:3, 4 mL) at room temperature for 40 s and filtered; the filter cake was washed with a mixture of ethyl acetate and heptane (1:3, 5 x 2 mL), to e N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}-N2-(2,6-dichlorobenzoyl)methyl-L-leucinamide (3) as a solid.

Combined yield: 70 mg, 0.15 mmol, 59%. LCMS m/z 453.3 (dichloro isotope pattern observed) [M+H]+. 1H NMR (400 MHz, methanol-d 4)  7.45 – 7.34 (m, 3H), 5.05 (dd, J = .7, 5.4 Hz, 1H), 4.56 (dd, J = 7.0, 5.7 Hz, 1H), 3.37 – 3.23 (m, 2H, assumed; partially obscured by solvent peak), 2.70 – 2.59 (m, 1H), 2.42 – 2.29 (m, 2H), 1.95 – 1.77 (m, 3H), 1.67 (dd, component of ABX system, J = 14.4, 7.0 Hz, 1H), 1.04 (s, 9H).

Example 4 N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide (4) Step 1. Synthesis of methyl yl[(3S)oxopyrrolidinyl]-L-alaninate, hydrochloride salt (C20).

A solution of methyl N-(tert-butoxycarbonyl)-L-leucyl[(3S)oxopyrrolidinyl]- L-alaninate (see Prior, A.M., et al., Bioorg. Med. Chem. Lett. 2013, 23, 6317–6320; 2.0 g, 5.0 mmol) in a mixture of methanol (2 mL) and a solution of hydrogen chloride in ethyl acetate (4 M; 20 mL) was stirred at 25 °C for 1 hour. Concentration in vacuo afforded C20 as a white solid (1.92 g, assumed quantitative). 1H NMR (400 MHz, DMSO-d6), characteristic peaks:  9.09 – 8.98 (m, 1H), 8.39 (br s, 3H), 7.69 (s, 1H), 4.44 – 4.31 (m, 1H), 3.22 – 3.07 (m, 2H), 2.5 – 2.38 (m, 1H, assumed; partially obscured by solvent peak), 2.24 – 2.11 (m, 1H), 2.11 – 1.99 (m, 1H), 1.78 – 1.48 (m, 5H), 0.92 (d, J = 6.5 Hz, 3H), 0.89 (d, J = 6.5 Hz, 3H).

Step 2. Synthesis of methyl ethoxy-1H-indolecarbonyl)-L-leucyl[(3S) oxopyrrolidinyl]-L-alaninate (C21).

O-(7-Azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 494 mg, 1.30 mmol) and isopropylethylamine (388 mg, 3.00 mmol) were added to a 0 °C solution of C20 (from a smaller-scale experiment similar to Step 1; 336 mg, ≤0.840 mmol) and oxy-1H-indolecarboxylic acid (159 mg, 0.832 mmol) in N,N-dimethylformamide (6 mL). The solution was stirred at 0 °C for 1.5 hours, whereupon it was poured into water / ice (10 mL) and ted with ethyl acetate (3 x mL). The combined organic layers were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. Silica gel chromatography (Eluent: 10:1 dichloromethane / methanol) provided C21 as a yellow oil. Yield: 380 mg, 0.804 mmol, 97%. LCMS m/z 473.2 [M+H]+. 1H NMR (400 MHz, DMSO-d6)  11.59 – 11.53 (m, 1H), 8.53 (d, J = 8.0 Hz, 1H), 8.37 (d, J = 8.0 Hz, 1H), 7.65 (s, 1H), 7.37 – 7.33 (m, 1H), 7.09 (dd, J = 8, 8 Hz, 1H), 7.00 (d, component of AB t, J = 8.2 Hz, 1H), 6.50 (d, J = 7.6 Hz, 1H), 4.56 – 4.47 (m, 1H), 4.40 – 4.31 (m, 1H), 3.88 (s, 3H), 3.62 (s, 3H), 3.18 – 3.05 (m, 2H), 2.41 – 2.29 (m, 1H), 2.15 – 2.03 (m, 2H), 1.78 – 1.49 (m, 5H), 0.93 (d, J = 6.3 Hz, 3H), 0.89 (d, J = 6.4 Hz, 3H).

Step 3. Synthesis of N-(4-methoxy-1H-indolecarbonyl)-L-leucyl[(3S) oxopyrrolidinyl]-L-alanine (C22).

To a stirring mixture of calcium chloride (0.887 g, 7.99 mmol) and sodium ide (0.168 g, 4.20 mmol) in 2-propanol (7 mL) and water (3 mL) was added C21 (1.8 g, 3.8 mmol). The reaction mixture was stirred at 20 °C for 6 hours, whereupon it was concentrated in vacuo, diluted with water (4 mL), adjusted to pH 4 by addition of 1 M hydrochloric acid, and extracted with ethyl e (3 x 10 mL). The combined organic layers were washed with ted aqueous sodium chloride on, dried over sodium sulfate, ed, and concentrated in vacuo. Silica gel chromatography (Eluent: 10:1:0.1 romethane / methanol / acetic acid) afforded C22 as a yellow solid. Yield: 1.76 g, 3.84 mmol, 100%. LCMS m/z 459.2 [M+H]+. 1H NMR (400 MHz, chloroform-d), characteristic peaks:  6.51 – 6.43 (m, 1H), 4.80 – 4.66 (m, 1H), 4.60 – 4.45 (m, 1H), 3.92 (s, 3H), 3.36 – 3.18 (m, 2H), 2.59 – 2.44 (m, 1H).

Alternate Step 3. Synthesis of N-(4-methoxy-1H-indolecarbonyl)-L-leucyl[(3S) oxopyrrolidinyl]-L-alanine (C22).

A solution of C21 (20 mg, 42 µmol) in tetrahydrofuran (0.4 mL) was treated with an aqueous solution containing lithium hydroxide (14.2 mg, 0.593 mmol). After the reaction mixture had been stirred at room ature for 2.5 hours, it was diluted with ethyl acetate and washed with 10% aqueous potassium bisulfate solution. The organic layer was then dried over sodium sulfate, filtered, and concentrated in vacuo, providing C22 as a white solid. Yield: 20 mg, quantitative. LCMS m/z 459.2 [M+H]+. 1H NMR (400 MHz, methanol-d4)  7.27 (s, 1H), 7.14 (dd, component of ABX system, J = 8, 8 Hz, 1H), 7.02 (d, component of AB quartet, J = 8.3 Hz, 1H), 6.50 (d, J = 7.7 Hz, 1H), 4.66 (dd, J = 9.0, 5.9 Hz, 1H), 4.52 (dd, J = 11.7, 3.9 Hz, 1H), 3.92 (s, 3H), 3.30 – 3.18 (m, 2H), 2.65 – 2.52 (m, 1H), 2.38 – 2.26 (m, 1H), 2.21 (ddd, J = 14.0, 11.7, 4.1 Hz, 1H), 1.90 – 1.70 (m, 5H), 1.02 (d, J = 6.3 Hz, 3H), 0.99 (d, J = 6.3 Hz, 3H).

Step 4. Synthesis of ethoxy-1H-indolecarbonyl)-L-leucyl[(3S) oxopyrrolidinyl]-L-alaninamide (C23).

To a 0 °C solution of C22 (1.76 g, 3.84 mmol) and ammonium chloride (0.246 g, 4.60 mmol) in N,N-dimethylformamide (15 mL) were added O-(7-azabenzotriazolyl)- N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 1.90 g, 5.00 mmol) and N,N-diisopropylethylamine (1.49 g, 11.5 mmol). After the on mixture had been stirred at 0 °C for 1.5 hours, N,N-diisopropylethylamine (2.3 g, 18 mmol) was used to adjust the pH to 8. The reaction mixture was stirred for an additional 30 minutes, whereupon it was poured into a mixture of hydrochloric acid (1 M; 20 mL, 20 mmol) and ice. The resulting mixture was extracted with ethyl acetate (3 x 10 mL); the ed organic layers were washed sequentially with hydrochloric acid (1 M; 10 mL) and saturated aqueous sodium chloride solution (10 mL), dried over sodium sulfate, filtered, concentrated in vacuo, and purified via silica gel chromatography t: 10:1 dichloromethane / methanol), affording C23 as a yellow solid. Yield: 1.09 g, 2.38 mmol, 62%. LCMS m/z 458.0 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  11.62 – 11.55 (m, 1H), 8.42 (d, J = 7.9 Hz, 1H), 8.04 (d, J = 8.4 Hz, 1H), 7.60 (br s, 1H), 7.38 – 7.26 (m, 2H), 7.10 (dd, component of ABX system, J = 8, 8 Hz, 1H), 7.06 (br s, 1H), 7.00 (d, component of AB quartet, J = 8.2 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 4.54 – 4.41 (m, 1H), 4.34 – 4.22 (m, 1H), 3.88 (s, 3H), 3.17 – 3.01 (m, 2H), 2.31 – 1.95 (m, 3H), 1.76 – 1.45 (m, 5H), 0.92 (d, J = 6.1 Hz, 3H), 0.88 (d, J = 6.3 Hz, 3H).

Step 5. Synthesis of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- 4-methyloxopentanyl]methoxy-1H-indolecarboxamide (4).

To a 0 °C mixture of C23 (500 mg, 1.09 mmol) and N,N-diisopropylethylamine (565 mg, 4.37 mmol) in tetrahydrofuran (8 mL) was added 2,4,6-tripropyl-1,3,5,2,4,6- trioxatriphosphinane trioxide (50% solution by weight in ethyl acetate; 2.78 g, 4.37 mmol). After the reaction mixture had been stirred at 50 °C for 3 hours, it was concentrated in vacuo, d with water (5 mL), and extracted with ethyl acetate (3 x 5 mL). The combined organic layers were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, ed, and concentrated in vacuo; silica gel chromatography (Eluent: 10:1 dichloromethane / methanol) followed by reversedphase HPLC purification (Column: YMC-Actus Triart C18, 50 x 250 mm, 7 µm; Mobile phase A: water containing 0.225% formic acid; Mobile phase B: acetonitrile; Gradient: 18% to 58% B; Flow rate: 25 mL/minute) afforded N-[(2S)({(1S)cyano[(3S) oxopyrrolidinyl]ethyl}amino)methyloxopentanyl]methoxy-1H-indole carboxamide (4) as a yellow solid. Yield: 130 mg, 0.296 mmol, 27%. LCMS m/z 440.2 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  11.58 (br s, 1H), 8.90 (d, J = 8.0 Hz, 1H), 8.47 (d, J = 7.7 Hz, 1H), 7.71 (br s, 1H), 7.38 – 7.35 (m, 1H), 7.09 (dd, component of ABX system, J = 8, 8 Hz, 1H), 7.00 (d, component of AB quartet, J = 8.2 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 5.02 – 4.93 (m, 1H), 4.49 – 4.40 (m, 1H), 3.88 (s, 3H), 3.19 – 3.05 (m, 2H), 2.41 – 2.29 (m, 1H), 2.20 – 2.06 (m, 2H), 1.85 – 1.62 (m, 4H), 1.58 – 1.47 (m, 1H), 0.94 (d, J = 6.3 Hz, 3H), 0.89 (d, J = 6.3 Hz, 3H).

Alternate Synthesis of Example 4 N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy-1H-indolecarboxamide (4) Step 1. Synthesis of N-[(4-methoxy-1H-indolyl)carbonyl]-L-leucyl[(3S) oxopyrrolidinyl]-L-alaninamide (C23).

A solution of ammonia in methanol (7.0 M; 21 mL, 150 mmol) was added to a solution of C21 (500 mg, 1.06 mmol) in methanol (2.0 mL). After the reaction e had been stirred at room temperature for 6 hours, a solution of ammonia in methanol (7.0 M; 7.0 mL, 49 mmol) was again added, and stirring was continued overnight. A solution of ammonia in methanol (7.0 M; 7.0 mL, 49 mmol) was again added, and stirring was continued for 24 hours, whereupon a final treatment with a solution of ammonia in methanol (7.0 M; 7.0 mL, 49 mmol) was carried out. The reaction mixture was stirred for one more day, at which point it was concentrated in vacuo. The e was ed with the product of a similar reaction (350 mg of the 512 mg isolated) carried out using C21 (500 mg, 1.06 mmol), and the mixture was edly dissolved in ethyl acetate (5 x 10 mL) and concentrated under reduced pressure, providing C23 (835 mg). This material was used directly in the following step. LCMS m/z 458.4 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  7.29 (d, J = 0.9 Hz, 1H), 7.15 (dd, component of ABX system, J = 8, 8 Hz, 1H), 7.03 (br d, component of AB t, J = 8.3 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 4.59 (dd, J = 9.7, 5.0 Hz, 1H), 4.45 (dd, J = 11.3, 4.2 Hz, 1H), 3.93 (s, 3H), 3.34 – 3.19 (m, 2H, assumed; lly obscured by solvent peak), 2.57 – 2.47 (m, 1H), 2.31 (dddd, J = 12.6, 8.5, 6.8, 2.8 Hz, 1H), 2.15 (ddd, J = 14.0, 11.4, 4.6 Hz, 1H), 1.88 – 1.67 (m, 5H), 1.02 (d, J = 6.1 Hz, 3H), 0.98 (d, J = 6.1 Hz, 3H).

Step 2. Synthesis of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- yloxopentanyl]methoxy-1H-indolecarboxamide (4).

A solution of C23 (from the previous step; 835 mg, ≤1.78 mmol) and 1H- imidazole (323 mg, 4.74 mmol) in a mixture of pyridine (4 mL) and dichloromethane (4 mL) was cooled to −35 °C using an acetonitrile / dry ice bath, whereupon phosphorus oxychloride (0.956 mL, 10.2 mmol) was added in a drop-wise manner over 5 minutes.

The reaction was stirred at a temperature between −30 °C and −20 °C for about 1.5 hours, then treated with hydrochloric acid (1 M; 50 mL) and stirred for 1 hour. After tion with dichloromethane (3 x 60 mL), the resulting organic layers were combined, dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was combined with purified 4 from a different batch (75 mg, 0.17 mmol) and subjected to silica gel chromatography (Gradient: 0% to 5% methanol in ethyl acetate) to provide 4 as a solid (800 mg). This al was ed with the product (80 mg) from a similar reaction d out using C23 (161 mg, 0.352 mmol); the resulting material was d in diethyl ether (25 mL) for 3 days, whereupon it was filtered. The filter cake was washed with a mixture of diethyl ether and heptane (1:1, 4 x 2 mL) to afford N-[(2S) ({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyloxopentanyl] methoxy-1H-indolecarboxamide (4) as a solid. Combined yield: 519 mg, 1.18 mmol, approximately 50% over 2 steps. LCMS m/z 440.5 [M+H]+. 1H NMR (400 MHz, DMSO- d6)  11.57 (d, J = 2.3 Hz, 1H), 8.90 (d, J = 8.1 Hz, 1H), 8.46 (d, J = 7.7 Hz, 1H), 7.70 (s, 1H), 7.37 (d, J = 2.3 Hz, 1H), 7.10 (dd, component of ABX system, J = 8, 8 Hz, 1H), 7.00 (d, component of AB t, J = 8.2 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 5.03 – 4.92 (m, 1H), 4.51 – 4.39 (m, 1H), 3.88 (s, 3H), 3.19 – 3.05 (m, 2H), 2.42 – 2.30 (m, 1H), 2.20 – 2.06 (m, 2H), 1.80 (ddd, J = 13.2, 9.3, 6.7 Hz, 1H), 1.75 – 1.63 (m, 3H), 1.58 – 1.47 (m, 1H), 0.94 (d, J = 6.2 Hz, 3H), 0.89 (d, J = 6.2 Hz, 3H).

Examples 5 and 6 N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide (5) and N- [(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyloxopentan- 2-yl]methoxy(trifluoromethyl)-1H-indolecarboxamide (6) To a pressure release vial containing zinc(II) trifluoromethanesulfinate (98%, 2.44 mg, 7.21 µmol) were sequentially added a solution of 4 (0.79 mg, 1.8 µmol) in dimethyl sulfoxide (60 µL), trifluoroacetic acid (0.56 µL, 7.3 µmol), and tert-butyl hydroperoxide (70% in water; 1.25 uL, 9.03 µmol). The vial was capped and heated to 50 °C overnight, whereupon the reaction mixture was cooled and diluted with acetonitrile and a 1% solution of formic acid in water, to a volume of approximately 2 to 3 mL. The final solvent composition was such that the resulting mixture appeared clear, lly about 20% to 30% acetonitrile. The entire mixture was ted to reversed- phase HPLC (Column: enex Luna C18 ,10 x 250 mm, 10 µm; Mobile phase A: 0.5% acetic acid in water; Mobile phase B: 9:1 acetonitrile / methanol; Gradient: 15% B for 5 minutes, then 15% to 70% B linear gradient over 84 minutes, then 70% to 95% B over 1 minute, then 95% B for 9 s; Flow rate: 2 mL/min). The eluate was passed through a UV/VIS detector and then was split at approximately 15:1 between a fraction collector and an ion trap mass spectrometer. ons were ted every 20 seconds and those potentially containing products of interest were evaluated by UHPLC-UV-HRMS before pooling. The two products eluted at approximately 71 and 75 minutes. The first-eluting product was 5 {N-[(2S)({(1S)cyano[(3S) oxopyrrolidinyl]ethyl}amino)methyloxopentanyl]methoxy (trifluoromethyl)-1H-indolecarboxamide}, and the second-eluting was 6 {N-[(2S) cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyloxopentanyl] methoxy(trifluoromethyl)-1H-indolecarboxamide}.

– Yield: 0.101 mg, 0.199 µmol, 11%. High-resolution MS m/z 508.2171 [M+H]+; calculated for C24H29F3N5O4, 508.2172. 1H NMR (600 MHz, DMSO-d 6)  12.22 (br s, 1H), 9.01 (d, J = 7.6 Hz, 1H), 8.96 (d, J = 7.9 Hz, 1H), 7.73 (s, 1H), 7.21 (dd, J = 8, 8 Hz, 1H), 7.08 (d, J = 8.2 Hz, 1H), 6.69 (d, J = 7.8 Hz, 1H), 5.03 – 4.95 (m, 1H), 4.49 – 4.40 (m, 1H), 3.87 (s, 3H), 3.22 – 3.08 (m, 2H), 2.43 – 2.34 (m, 1H), 2.23 – 2.10 (m, 2H), 1.82 (ddd, J = 13.7, 9.3, 6.8 Hz, 1H), 1.78 – 1.66 (m, 2H), 1.62 (ddd, J = 14.6, 9.7, .2 Hz, 1H), 1.49 (ddd, J = 13.8, 8.8, 5.5 Hz, 1H), 0.97 – 0.88 (m, 6H). ion time: 8.43 minutes (Analytical conditions. Column: Phenomenex Kinetex XB-C18, 2.1 x 100 mm, 2.6 µm; Mobile phase A: water containing 0.1% formic acid; Mobile phase B: acetonitrile; Gradient: 5% B for 0.5 minutes, then 5% to 70% B over 10.5 minutes, then 70% to 95% B over 2 minutes; Flow rate: 0.4 ). 6 – Yield: 14.7 µg, 0.029 µmol, 1.6%. High-resolution MS m/z 508.2178 [M+H]+; calculated for C24H29F3N5O4, 508.2172. 1H NMR (600 MHz, DMSO-d 6)  11.47 (br s, 1H), 9.00 (d, J = 7.9 Hz, 1H), 8.79 (d, J = 7.8 Hz, 1H), 7.70 (s, 1H), 7.55 (d, J = 8.2 Hz, 1H), 7.35 (s, 1H), 6.72 (d, J = 8.3 Hz, 1H), 5.02 – 4.94 (m, 1H), 4.56 – 4.48 (m, 1H), 3.97 (s, 3H), 3.18 – 3.05 (m, 2H), 2.39 – 2.30 (m, 1H), 2.18 – 2.08 (m, 2H), 1.86 – 1.77 (m, 1H), 1.75 – 1.64 (m, 3H), 1.61 – 1.52 (m, 1H), 0.95 (d, J = 6.1 Hz, 3H), 0.90 (d, J = 6.1 Hz, 3H). Retention time: 8.92 minutes (Analytical conditions cal to those used for 5).

Alternate Synthesis of Example 6 N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyl oxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide (6) Step 1. Synthesis of trifluoromethylated 4-methoxy-1H-indolecarboxylic acid (C24).

A mixture of 4-methoxy-1H-indolecarboxylic acid (100 mg, 0.523 mmol) and zinc(II) trifluoromethanesulfinate (120 mg, 0.362 mmol) was treated with dimethyl sulfoxide (1.5 mL) followed by trifluoroacetic acid (56 µL, 0.727 mmol). After the reaction mixture had been cooled to 0 °C, utyl hydroperoxide (70% in water; 143 µL, 1.03 mmol) was added, and stirring was continued at 0 °C for 20 minutes, then at room temperature for 25 minutes. The reaction mixture was subsequently heated at 52 °C for 2 hours, whereupon it was cooled to room temperature and treated in a dropwise manner with aqueous sodium bicarbonate solution until bubbling had ceased. After the ing mixture had been partitioned between s sodium bicarbonate solution and ethyl acetate, the s layer was extracted once with ethyl acetate and the organic layers were discarded. The s layer was then acidified to pH 7 with 1 M hydrochloric acid; ethyl acetate was added, and the mixture was stirred while the pH was adjusted to 1 by addition of 1 M hloric acid. After the biphasic mixture had been stirred for 10 minutes, the organic layer was washed with saturated aqueous sodium chloride solution, dried over magnesium sulfate, filtered, and concentrated in vacuo. By LCMS analysis, the e (115 mg) contained a mixture of starting material and rifluoromethylated products, as well as a small amount of ditrifluoromethylated material. The bulk of this mixture was used in Step 4. Yield: 115 mg, <0.4 mmol. LCMS m/z 189.8, 257.8, 325.8 (minor) [M−H]−. 1H NMR (400 MHz, methanol-d4), characteristic peaks from the three major components:  7.07 (br d, J = 8.4 Hz), 7.02 (br d, J = 8.4 Hz), 6.81 (d, J = 7.8 Hz), 6.66 (d, J = 7.8 Hz), 6.51 (d, J = 7.7 Hz), 4.06 (s, -OMe), 3.93 (s, -OMe), 3.92 (s, -OMe).

Step 2. Synthesis of N-(tert-butoxycarbonyl)-L-leucyl[(3S)oxopyrrolidinyl]-L- alaninamide (C25).

To a 0 °C on of methyl N-(tert-butoxycarbonyl)-L-leucyl[(3S) oxopyrrolidinyl]-L-alaninate (see Prior, A.M., et al., Bioorg. Med. Chem. Lett. 2013, 23, 6317–6320; 1.5 g, 3.8 mmol) in methanol (5 mL) was added a solution of ammonia in ol (7 M; 43 mL, 300 mmol). After the reaction vessel had been capped, the reaction mixture was stirred overnight at room temperature. A solution of ammonia in ol (7 M; 10.7 mL, 74.9 mmol) was again added, and the reaction was allowed to continue at room temperature for 3 days, whereupon it was concentrated in vacuo. The residue was taken up twice in diethyl ether (40 mL) and concentrated under reduced pressure, affording C25 as a white solid. Yield: 1.46 g, 3.80 mmol, quantitative. LCMS m/z 385.4 [M+H]+. 1H NMR (400 MHz, chloroform-d)  8.29 – 8.17 (m, 1H), 7.23 (br s, 1H), 5.64 (br s, 1H), 5.32 (br s, 1H), 5.02 (d, J = 6.1 Hz, 1H), 4.50 – 4.38 (m, 1H), 4.05 (ddd, J = 10.3, 6.3, 4.5 Hz, 1H), 3.44 – 3.32 (m, 2H), 2.51 – 2.35 (m, 2H), 2.16 – 1.98 (m, 2H), 1.97 – 1.83 (m, 1H), 1.76 – 1.6 (m, 2H, assumed; partially obscured by water peak), 1.49 – 1.39 (m, 1H), 1.45 (s, 9H), 0.94 (d, J = 6.4 Hz, 3H), 0.94 (d, J = 6.3 Hz, Step 3. Synthesis of yl[(3S)oxopyrrolidinyl]-L-alaninamide, methanesulfonate salt (C26).

A solution of methanesulfonic acid (0.861 mL, 13.3 mmol) in 1,1,1,3,3,3- hexafluoropropanol (5 mL) was slowly added to a solution of C25 (5.1 g, 13 mmol) in 1,1,1,3,3,3-hexafluoropropanol (43 mL). After 30 minutes, LCMS analysis indicated conversion to C26: LCMS m/z 285.3 [M+H]+. The on mixture was concentrated in vacuo, then taken up in the following solvent mixtures and entrated: a mixture of acetonitrile and ethyl acetate (1:1, 2 x 20 mL), then a mixture of ethyl acetate and heptane, (1:1, 2 x 20 mL). The resulting solid was azeotroped twice with a mixture of acetonitrile and ethyl acetate, then twice with a mixture of ethyl acetate and heptane, affording C26 as a white solid (6.05 g) that retained solvents by 1H NMR is. Yield: assumed quantitative. 1H NMR (600 MHz, methanol-d 4)  4.50 (dd, J = 10.7, 4.9 Hz, 1H), 3.91 (dd, J = 8.6, 5.5 Hz, 1H), 3.39 – 3.28 (m, 2H, assumed; partially obscured by solvent peak), 2.70 (s, 3H), 2.53 – 2.46 (m, 1H), 2.43 – 2.36 (m, 1H), 2.14 (ddd, J = 14.0, 10.7, 5.0 Hz, 1H), 1.95 – 1.86 (m, 1H), 1.82 – 1.71 (m, 3H), 1.70 – 1.64 (m, 1H), 1.02 (d, J = 6.3 Hz, 3H), 1.01 (d, J = 6.1 Hz, 3H).

Step 4. Synthesis of N-{[4-methoxy(trifluoromethyl)-1H-indolyl]carbonyl}-L-leucyl- 3-[(3S)oxopyrrolidinyl]-L-alaninamide (C27).

A solution of C24 (from Step 1; 101 mg, <0.35 mmol) and C26 (from the previous step; 204 mg, ≤0.438 mmol) in itrile (1.7 mL) and N,N-dimethylformamide (1 mL) was cooled to 0 °C and treated with O-(7-azabenzotriazolyl)-N,N,N’,N’- tetramethyluronium hexafluorophosphate (HATU; 163 mg, 0.429 mmol) followed by 4- methylmorpholine (0.129 mL, 1.17 mmol). The reaction mixture was stirred at 0 °C for 40 minutes, whereupon a 1:1 mixture of s sodium bicarbonate on and ice was slowly added until a cloudy precipitate . Ethyl acetate was then added, and the biphasic mixture was stirred for 5 minutes. The aqueous layer was extracted once with ethyl acetate, and the combined organic layers were washed with saturated aqueous sodium de solution, dried over magnesium sulfate, filtered, and concentrated in vacuo. Purification via silica gel tography was carried out twice (Gradient #1: 0% to 10% methanol in dichloromethane; nt #2: 5% to 10% methanol in dichloromethane) to afford C27. The regiochemistry of this material was confirmed by 2D NMR experiments. Yield: 19 mg, 36 µmol, approximately 10%. LCMS m/z 526.5 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  7.53 (br d, J = 8.2 Hz, 1H), 7.41 (s, 1H), 6.68 (d, J = 8.3 Hz, 1H), 4.60 (dd, J = 9.5, 5.1 Hz, 1H), 4.45 (dd, J = 11.4, 4.2 Hz, 1H), 4.01 (s, 3H), 3.3 – 3.21 (m, 2H, assumed; partially obscured by solvent peak), 2.60 – 2.49 (m, 1H), 2.36 – 2.26 (m, 1H), 2.15 (ddd, J = 14.1, 11.5, 4.6 Hz, 1H), 1.89 – 1.68 (m, 5H), 1.03 (d, J = 6.1 Hz, 3H), 0.99 (d, J = 6.2 Hz, 3H).

Step 5. Synthesis of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- 4-methyloxopentanyl]methoxy(trifluoromethyl)-1H-indolecarboxamide (6).

Methyl N-(triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 17.2 mg, 72.2 µmol) was added to a solution of C27 (19 mg, 36 µmol) in a mixture of dichloromethane (0.5 mL) and acetonitrile (0.2 mL). After the on mixture had been stirred at room temperature for 1 hour, it was diluted with ethyl acetate and washed with a 1:1 mixture of aqueous sodium bicarbonate solution and ice. The aqueous layer was extracted with ethyl acetate, and the combined organic layers were washed with saturated aqueous sodium chloride solution, and passed through a solid-phase extraction cartridge packed with ium sulfate. tration of the filtrate in vacuo provided a residue, which was purified via reversed-phase HPLC (Column: Waters Sunfire C18, 19 x 100 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v); Gradient: 25% to 65% B over 8.5 minutes, then 65% to 95% B over 0.5 minutes, then 95% B for 1.0 ; Flow rate: 25 mL/minute) to afford N-[(2S)({(1S)- 1-cyano[(3S)oxopyrrolidinyl]ethyl}amino)methyloxopentanyl] methoxy(trifluoromethyl)-1H-indolecarboxamide (6). Yield: 4.3 mg, 8.5 µmol, 24%.

LCMS m/z 508.6 [M+H]+. Retention time: 2.83 minutes n: Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: itrile containing 0.05% trifluoroacetic acid (v/v); nt: 5% to 95% B over 4.0 minutes, then 95% B for 1.0 minute; Flow rate: 2 mL/minute).

Example 7 N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methylimidazo[2,1-b][1,3]thiazolecarboxamide (7) Step 1. Synthesis of N2-(tert-butoxycarbonyl)-N-{(1S)cyano[(3S)oxopyrrolidin yl]ethyl}methyl-L-leucinamide (C28).

A solution of C17 (560 mg, 1.41 mmol) and 1H-imidazole (249 mg, 3.65 mmol) in a mixture of pyridine (3 mL) and dichloromethane (3 mL) was cooled to −35 °C using an acetonitrile / dry ice bath. Phosphorus oxychloride (0.74 mL, 7.94 mmol) was added in a drop-wise manner, over 4 minutes, followed by additional dichloromethane (2 mL), and ng was continued at −30 °C to −20 °C. After 1 hour, the reaction mixture was diluted with dichloromethane (2 mL). After approximately 1.5 hours, hydrochloric acid (1 M; 30 mL) was added; the ing mixture was d for 30 minutes, and then extracted with dichloromethane (2 x 60 mL). The combined organic layers were dried over sodium e, ed, and concentrated in vacuo, affording C28 as a solid. Yield: 492 mg, 1.29 mmol, 91%. LCMS m/z 381.4 [M+H]+. 1H NMR (400 MHz, methanol-d4)  .03 (dd, J = 10.4, 5.7 Hz, 1H), 4.09 (dd, J = 8.7, 4.2 Hz, 1H), 3.39 – 3.25 (m, 2H, assumed; partially ed by solvent peak), 2.64 – 2.52 (m, 1H), 2.40 – 2.27 (m, 2H), 1.97 – 1.78 (m, 2H), 1.70 (dd, component of ABX system, J = 14.3, 4.1 Hz, 1H), 1.54 (dd, component of ABX system, J = 14.3, 8.7 Hz, 1H), 1.45 (s, 9H), 1.00 (s, 9H).

Step 2. Synthesis of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- 4,4-dimethyloxopentanyl]methylimidazo[2,1-b][1,3]thiazolecarboxamide (7).

A solution of hydrogen chloride in 1,4-dioxane (4.0 M; 0.3 mL, 1.2 mmol) was added to a on of C28 (100 mg, 0.263 mmol) in a mixture of acetonitrile (1.5 mL) and methanol (1.0 mL). The reaction mixture was stirred at room temperature for 30 minutes, whereupon it was treated with 4-methylmorpholine (0.144 mL, 1.31 mmol).

After solvents had been removed in vacuo, the residue was twice resuspended in a mixture of dichloromethane and heptane (1:1, 2 x 10 mL) and concentrated under d pressure. The residue was combined with 3-methylimidazo[2,1-b][1,3]thiazole- 2-carboxylic acid (47.9 mg, 0.263 mmol) in N,N-dimethylformamide (3.3 mL), cooled to 0 °C, and treated with O-(7-azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 99.9 mg, 0.263 mmol) followed by a solution of 4- methylmorpholine (72 µL, 0.655 mmol) in dichloromethane (0.2 mL). After the reaction mixture had been stirred at 0 °C for approximately 2 hours, it was treated at 0 °C with hydrochloric acid (1 M; 30 mL), and the resulting mixture was extracted with romethane (2 x 60 mL). The aqueous layer was then basified to pH 9 by on of saturated aqueous sodium bicarbonate solution, whereupon it was extracted with dichloromethane (3 x 60 mL). The combined organic layers were washed with ted aqueous ammonium chloride solution (50 mL), dried over sodium e, ed, and concentrated in vacuo. 1H NMR analysis of this material indicated the presence of a minor epimer, presumed to arise from partial racemization at the center bearing the nitrile. The major product was isolated using silica gel chromatography (Gradient: 0% to % methanol in ethyl acetate), providing N-[(2S)({(1S)cyano[(3S) oxopyrrolidinyl]ethyl}amino)-4,4-dimethyloxopentanyl]methylimidazo[2,1- b][1,3]thiazolecarboxamide (7) as a solid. Yield: 56 mg, 0.13 mmol, 49%. LCMS m/z 445.4 [M+H]+. 1H NMR (400 MHz, methanol-d 4)  7.73 (d, J = 1.6 Hz, 1H), 7.37 (d, J = 1.6 Hz, 1H), 5.04 (dd, J = 10.3, 5.9 Hz, 1H), 4.53 (dd, J = 7.8, 5.0 Hz, 1H), 3.36 – 3.24 (m, 2H; d; partially obscured by solvent peak), 2.70 (s, 3H), 2.67 – 2.57 (m, 1H), 2.38 – 2.27 (m, 2H), 1.93 (ddd, J = 14.0, 9.4, 6.0 Hz, 1H), 1.88 – 1.78 (m, 3H), 1.03 (s, Examples 8 and 9 N-{1-Cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[cyclohexyl(methoxy)acetyl]methyl- L-leucinamide, DIAST-1 (8) and N-{1-Cyano[(3S)oxopyrrolidinyl]ethyl}-N2- [cyclohexyl(methoxy)acetyl]methyl-L-leucinamide, DIAST-2 (9) Step 1. Synthesis of N-{1-cyano[(3S)oxopyrrolidinyl]ethyl}methyl-L- leucinamide (C29).

To a solution of C28 (114 mg, 0.300 mmol) in a mixture of acetonitrile (1 mL) and methanol (1 mL) was added a solution of hydrogen chloride in 1,4-dioxane (4 M; 0.4 mL, 1.6 mmol). The reaction mixture was stirred at room temperature for 30 minutes, whereupon 4-methylmorpholine (0.165 mL, 1.50 mmol) was added, ng the pH to 7 to 8. After solvents were removed in vacuo, the residue was twice taken up in a mixture of ethyl acetate and heptane (1:1, 2 x 10 mL) and concentrated under reduced pressure to provide C29 as a solid (269 mg); by 1H NMR analysis, this consisted of a mixture of epimers, presumed to be at the center bearing the nitrile, in a ratio of 2–3 to 1. A portion of this al was used in the ing step. LCMS m/z 281.3 [M+H]+. 1H NMR (400 MHz, methanol-d4), characteristic peaks:  [5.11 (dd, J = 8.8, 7.3 Hz, major) and 5.01 (dd, J = 6.5, 6.5 Hz, minor), total 1H], [2.75 – 2.65 (m, minor) and 2.64 – 2.54 (m, major), total 1H], 2.48 – 2.38 (m, 1H), 2.30 – 2.20 (m, 1H), 2.06 – 1.83 (m, 3H), 1.64 (dd, J = 14.1, 4.8 Hz, 1H), [1.04 (s, major), 1.01 (s, minor), total 9H].

Step 2. Synthesis of N-{1-cyano[(3S)oxopyrrolidinyl]ethyl}-N2- [cyclohexyl(methoxy)acetyl]methyl-L-leucinamide, DIAST-1 (8) and N-{1-cyano 2-oxopyrrolidinyl]ethyl}-N2-[cyclohexyl(methoxy)acetyl]methyl-L-leucinamide, DIAST-2 (9).

To a 0 °C solution of C29 (from the previous step; 83.4 mg, ≤93 µmol) and cyclohexyl(methoxy)acetic acid (17.2 mg, 99.9 µmol) in N,N-dimethylformamide (1 mL) was added O-(7-azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 38.0 mg, 0.100 mmol), followed by a on of 4- methylmorpholine (30.8 µL, 0.280 mmol) in dichloromethane (0.2 mL). After the reaction mixture had been stirred at 0 °C for about 2 hours, it was d with saturated aqueous sodium bicarbonate solution (3 mL) at 0 °C, and extracted with dichloromethane (4 x 4 mL). The combined organic layers were concentrated in vacuo; by LCMS analysis, the residue consisted of two components, assumed to correspond to the two epimers at the center bearing the nitrile. These diastereomers were ted via ed-phase HPLC n: Waters XBridge C18, 19 x 100 mm, 5 µm; Mobile phase A: water; Mobile phase B: acetonitrile; Gradient: 5% to 95% B over 8.54 minutes, then 95% B for 1.46 minutes; Flow rate: 25 mL/minute). The first-eluting diastereomer was designated as 8 (N-{1-cyano[(3S)oxopyrrolidinyl]ethyl}-N2- [cyclohexyl(methoxy)acetyl]methyl-L-leucinamide, DIAST-1), and the second-eluting diastereomer as 9 (N-{1-cyano[(3S)oxopyrrolidinyl]ethyl}-N2- [cyclohexyl(methoxy)acetyl]methyl-L-leucinamide, DIAST-2). 8 – Yield: 12.8 mg, 29.4 µmol, 32% over 2 steps. LCMS m/z 435.6 [M+H]+. Retention time: 2.63 minutes (Analytical conditions. Column: Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% oroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% oroacetic acid (v/v). Gradient: 5% to 95% B over 4.0 minutes, then 95% B for 1.0 minute. Flow rate: 2 mL/minute). 9 – Yield: 10 mg, 23.0 µmol, 25% over 2 steps. LCMS m/z 435.6 [M+H]+. Retention time: 2.72 minutes (Analytical conditions identical to those used for 8).

N-[(2S)({(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4-dimethyl oxopentanyl]methoxy-1H-indolecarboxamide (10) Step 1. Synthesis of N-[(4-methoxy-1H-indolyl)carbonyl]methyl-L-leucyl[(3S) oxopyrrolidinyl]-L-alaninamide (C30).

To a 0 °C solution of C18 (200 mg, ≤0.46 mmol) and 4-methoxy-1H-indole carboxylic acid (88.2 mg, 0.460 mmol) in acetonitrile (2 mL) was added O-(7- azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 175 mg, 0.460 mmol), followed by a solution of 4-methylmorpholine (0.127 mL, 1.16 mmol) in acetonitrile (0.2 mL). The reaction mixture was stirred at 0 °C for 2.5 hours, whereupon it was diluted with saturated aqueous sodium bicarbonate solution (30 mL) at 0 °C, then extracted with dichloromethane (50 mL). The organic layer was washed with hydrochloric acid (1 M; 30 mL), and the aqueous layers were extracted with dichloromethane (60 mL). After the combined organic layers had been dried over sodium sulfate, filtered, and concentrated in vacuo, the residue was purified via silica gel chromatography (Gradient: 0% to 30% methanol in ethyl acetate) to provide C30 as a solid. Yield: 148 mg, 0.314 mmol, 68% over 2 steps. LCMS m/z 472.4 [M+H]+. 1H NMR (400 MHz, methanol-d4)  7.25 (d, J = 0.9 Hz, 1H), 7.15 (dd, J = 8, 8 Hz, 1H), 7.03 (br d, ent of AB quartet, J = 8.3 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 4.65 (dd, J = 9.2, 3.4 Hz, 1H), 4.44 (dd, J = 11.2, 4.2 Hz, 1H), 3.93 (s, 3H), 3.29 – 3.15 (m, 2H), 2.54 – 2.44 (m, 1H), 2.29 (dddd, J = 12.6, 8.6, 7.0, 2.7 Hz, 1H), 2.14 (ddd, J = 14.0, 11.2, 4.6 Hz, 1H), 1.89 (dd, component of ABX system, J = 14.5, 3.4 Hz, 1H), 1.85 – 1.74 (m, 3H), 1.02 (s, 9H).

Step 2. Synthesis of N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)- 4,4-dimethyloxopentanyl]methoxy-1H-indolecarboxamide (10).

A solution of C30 (143 mg, 0.303 mmol) and 1H-imidazole (53.7 mg, 0.789 mmol) in a mixture of ne (1 mL) and dichloromethane (1 mL) was cooled in an acetonitrile / dry ice bath (−35 °C). Phosphorus oxychloride (0.159 mL, 1.71 mmol) was added in a drop-wise manner over 5 minutes, and the reaction mixture was d at −30 °C to −20 °C for 2 hours, whereupon it was treated with hydrochloric acid (1 M; 30 mL), stirred for 20 minutes, and extracted with dichloromethane (2 x 60 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Chromatography on silica gel ent: 0% to 10% methanol in ethyl acetate) ed N-[(2S)({(1S)cyano[(3S)oxopyrrolidinyl]ethyl}amino)-4,4- dimethyloxopentanyl]methoxy-1H-indolecarboxamide (10) as a solid. Yield: 68 mg, 0.15 mmol, 50%. LCMS m/z 454.5 . 1H NMR (400 MHz, methanol-d4)  7.24 (d, J = 0.9 Hz, 1H), 7.14 (dd, J = 8, 8 Hz, 1H), 7.02 (br d, component of AB quartet, J = 8.3 Hz, 1H), 6.51 (d, J = 7.7 Hz, 1H), 5.03 (dd, J = 10.1, 6.0 Hz, 1H), 4.64 (dd, J = 8.6, 4.3 Hz, 1H), 3.93 (s, 3H), 3.30 – 3.17 (m, 2H), 2.63 – 2.52 (m, 1H), 2.37 – 2.21 (m, 2H), 1.95 – 1.74 (m, 4H), 1.03 (s, 9H).

N2-[(4-Bromoethylmethyl-1H-pyrazolyl)carbonyl]-N-{(1S)cyano[(3S) oxopyrrolidinyl]ethyl}methyl-L-leucinamide (11) To a 0 °C slurry of C18 (43.4 mg, ≤0.10 mmol) and 4-bromoethylmethyl- 1H-pyrazolecarboxylic acid (23.3 mg, 0.100 mmol) in acetonitrile (1.0 mL) was added O-(7-azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 38.0 mg, 0.100 mmol), followed by a solution of 4-methylmorpholine (30 µL, 0.27 mmol) in itrile (0.2 mL). After the on mixture had been stirred at 0 °C for approximately 80 minutes, methyl N-(triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 71.5 mg, 0.300 mmol) was added, and stirring was continued. After approximately 2.75 hours, methyl ethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 71.5 mg, 0.300 mmol) was again added, and the reaction was allowed to proceed for 1.5 hours, whereupon it was treated with saturated aqueous sodium bicarbonate solution (3 mL) at 0 °C, and extracted with dichloromethane (2 x 8 mL). The combined organic layers were concentrated in vacuo, then dissolved in acetonitrile (4 mL) and concentrated again using a Genevac evaporator to provide the crude t (138 mg). A portion of this al (80 mg) was purified via reversed- phase HPLC (Column: Waters Sunfire C18, 19 x 100 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v); Gradient: 5% to 95% B over 8.54 minutes, then 95% B for 1.46 minutes; Flow rate: 25 mL/minute) to afford N2-[(4-bromoethylmethyl-1H- pyrazolyl)carbonyl]-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}methyl-L- leucinamide (11). Yield: 24.7 mg, 49.8 µmol, 86% over 2 steps. LCMS m/z 495.5 (bromine isotope pattern observed) [M+H]+. Retention time: 2.48 minutes (Analytical ions. Column: Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v). Gradient: 5% to 95% B over 4.0 s, then 95% B for 1.0 . Flow rate: 2 mL/minute).

Example 12 N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(3,3-difluorocyclobutyl)acetyl] methyl-L-leucinamide (12) Step 1. Synthesis of 4-methyl-L-leucyl[(3S)oxopyrrolidinyl]-L-alaninamide, hydrochloride salt (C18, HCl salt).

A solution of hydrogen chloride in 1,4-dioxane (4 M; 1.7 mL, 6.8 mmol) was added to a solution of C17 (260 mg, 0.652 mmol) in acetonitrile (3 mL). The reaction mixture was stirred at room temperature for 1.5 hours, whereupon it was concentrated in vacuo, then repeatedly dissolved in a mixture of dichloromethane and e (1:1, 3 x 10 mL) and re-concentrated, affording C18, HCl salt (242 mg) as a glass. A n of this material was used in the following step. LCMS m/z 299.3 [M+H]+. 1H NMR (400 MHz, methanol-d4)  4.53 (dd, J = 10.3, 5.0 Hz, 1H), 3.91 (dd, J = 7.5, 5.4 Hz, 1H), 3.41 – 3.26 (m, 2H, assumed; partially obscured by solvent peak), 2.57 – 2.47 (m, 1H), 2.41 (dddd, J = 12.0, 8.7, 7.0, 3.1 Hz, 1H), 2.15 (ddd, J = 13.9, 10.3, 4.9 Hz, 1H), 2.05 – 1.97 (m, 1H), 1.97 – 1.85 (m, 1H), 1.78 (ddd, J = 14.1, 9.1, 5.0 Hz, 1H), 1.60 (dd, J = 14.3, .4 Hz, 1H), 1.01 (s, 9H).

Step 2. Synthesis of )cyano[(3S)oxopyrrolidinyl]ethyl}-N2-[(3,3- difluorocyclobutyl)acetyl]methyl-L-leucinamide (12).

A slurry of C18, HCl salt (from the previous step; 37.2 mg, ≤0.100 mmol) and (3,3-difluorocyclobutyl)acetic acid (15.8 mg, 0.105 mmol) in tetrahydrofuran (1.0 mL) was treated with 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphinane 2,4,6-trioxide trioxide (50% solution by weight in ethyl acetate; 65.5 µL, 0.110 mmol) and 4-methylmorpholine (27.5 µL, 0.250 mmol). After the on e had been stirred at room temperature overnight, it was heated at 50 °C for 4.5 hours, whereupon 2,4,6-tripropyl-1,3,5,2,4,6- trioxatriphosphinane 2,4,6-trioxide trioxide (50% solution by weight in ethyl e; 2.2 equivalents) and 4-methylmorpholine (5 equivalents) were again added. After the reaction mixture had been stirred at 50 °C for 3 additional days, it was treated with saturated aqueous sodium bicarbonate solution (3 mL) and extracted with dichloromethane (4 x 4 mL). The combined organic layers were concentrated in vacuo and purified via reversed-phase HPLC (Column: Waters XBridge C18, 19 x 100 mm, 5 µm; Mobile phase A: water; Mobile phase B: acetonitrile; Gradient: 20% to 40% B over 8.5 s, then 40% to 95% B over 0.5 minutes, then 95% B for 1.0 ; Flow rate: 25 mL/minute) to afford N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-N2- [(3,3-difluorocyclobutyl)acetyl]methyl-L-leucinamide (12). Yield: 10.1 mg, 24.5 µmol, 24% over 2 steps. LCMS m/z 413.5 [M+H]+. Retention time: 1.96 minutes (Analytical conditions. Column: Waters Atlantis C18, 4.6 x 50 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% trifluoroacetic acid (v/v). Gradient: 5% to 95% B over 4.0 minutes, then 95% B for 1.0 minute. Flow rate: 2 mL/minute).

Example 13 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (13) Step 1. Synthesis of methyl (1R,2S,5S)[N-(tert-butoxycarbonyl)methyl-L-valyl]-6,6- dimethylazabicyclo[3.1.0]hexanecarboxylate (C31).

O-(7-Azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 7.92 g, 20.8 mmol) was added to a 0 °C mixture of N-(tert-butoxycarbonyl) methyl-L-valine (4.38 g, 18.9 mmol) and methyl (1R,2S,5S)-6,6-dimethyl azabicyclo[3.1.0]hexanecarboxylate, hydrochloride salt (3.9 g, 19 mmol) in N,N- dimethylformamide (95 mL). After the reaction mixture had been stirred for 5 minutes, isopropylethylamine (8.25 mL, 47.4 mmol) was added; stirring was continued at 0 °C for 2 hours, whereupon aqueous citric acid solution (1 N, 20 mL) and water (40 mL) were added. The resulting mixture was stirred for 2 minutes, and then diluted with ethyl acetate (250 mL). The organic layer was washed with water (3 x 150 mL) and with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. Purification via silica gel chromatography ent: 0% to 100% ethyl acetate in heptane) afforded C31 as an oil. Yield: 3.60 g, 9.41 mmol, 50%. 1H NMR (400 MHz, methanol-d4)  6.42 (d, J = 9.7 Hz, <1H; incompletely exchanged with solvent), 4.35 (s, 1H), 4.21 (d, J = 9.7 Hz, 1H), 4.02 (d, half of AB quartet, J = 10.4 Hz, 1H), 3.91 (dd, component of ABX , J = 10.3, 5.3 Hz, 1H), 3.73 (s, 3H), 1.57 (dd, component of ABX system, J = 7.5, 5.1 Hz, 1H), 1.47 (d, half of AB quartet, J = 7.5 Hz, 1H), 1.41 (s, 9H), 1.07 (s, 3H), 1.02 (s, 9H), 0.93 (s, 3H).

Step 2. Synthesis of (1R,2S,5S)[N-(tert-butoxycarbonyl)methyl-L-valyl]-6,6- dimethylazabicyclo[3.1.0]hexanecarboxylic acid (C32).

Aqueous lithium ide on (1.0 M; 14.7 mmol, 14.7 mL) was added in a drop-wise manner to a 0 °C solution of C31 (3.60 g, 9.41 mmol) in a mixture of tetrahydrofuran and methanol (1:1, 30 mL). After the reaction mixture had been d at 0 °C for 1 hour, it was allowed to warm to room temperature and stirred for 1 hour, whereupon LCMS analysis indicated conversion to C32: LCMS m/z 367.3 [M−H]−.

Adjustment to pH 3 was carried out via addition of 1 M hydrochloric acid, after which the mixture was diluted with water (30 mL). The s layer was ted with ethyl acetate (2 x 75 mL), and the combined c layers were dried over sodium sulfate, filtered, and trated under reduced pressure to provide C32 as an off-white solid.

Yield: 3.10 g, 8.41 mmol, 89%. 1H NMR (400 MHz, methanol-d 4)  6.39 (d, J = 9.7 Hz, approximately 0.5H; incompletely exchanged with solvent), 4.33 (s, 1H), [4.21 (d, J = 9.6 Hz) and 4.21 (s), total 1H], 4.01 (d, half of AB quartet, J = 10.5 Hz, 1H), 3.91 (dd, component of ABX system, J = 10.4, 5.2 Hz, 1H), 1.56 (dd, component of ABX system, J = 7.5, 5.0 Hz, 1H), 1.50 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.42 (s, 9H), 1.07 (s, 3H), 1.02 (s, 9H), 0.93 (s, 3H).

Step 3. Synthesis of tert-butyl {(2S)[(1R,2S,5S)({(1S)cyano[(3S) oxopyrrolidinyl]ethyl}carbamoyl)-6,6-dimethylazabicyclo[3.1.0]hexanyl]-3,3- dimethyloxobutanyl}carbamate (C33).

A 0 °C mixture of C7 (31.9 mg, ≤94 µmol) and C32 (34 mg, 92 µmol) in acetonitrile (1 mL) was treated with O-(7-azabenzotriazolyl)-N,N,N’,N’- tetramethyluronium hexafluorophosphate (HATU, 97%; 36.2 mg, 92.3 µmol) followed by a solution of 4-methylmorpholine (25 µL, 0.23 mmol) in acetonitrile (0.25 mL). After the reaction mixture had been stirred at 0 °C for approximately 1 hour, it was diluted with saturated aqueous sodium bicarbonate solution (3 mL) at 0 °C, and extracted with dichloromethane (4 x 4 mL). The combined organic layers were concentrated in vacuo to provide C33 as a gum (48 mg). Most of this material was used in the following step.

LCMS m/z 504.6 .

Step 4. Synthesis of (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- yl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide (13).

A stock solution of methanesulfonic acid (60 µL) in 1,1,1,3,3,3-hexafluoropropan- 2-ol (940 µL) was prepared. To a solution of C33 (from the previous step; 47 mg, ≤90 µmol) in 1,1,1,3,3,3-hexafluoropropanol (1 mL) was added a portion of the esulfonic acid stock solution (0.1 mL; 100 µmol). After the on mixture had been stirred at room temperature for 1 hour, it was concentrated in vacuo, then taken up in the following solvent es and reconcentrated: a mixture of acetonitrile and ethyl acetate (1:1, 2 x 10 mL), and then a mixture of ethyl acetate and heptane (1:1, 2 x mL). The residue was dissolved in dichloromethane (1 mL) and treated with 4- methylmorpholine (30.8 µL, 0.280 mmol), followed by trifluoroacetic anhydride (0.143 mL, 1.01 mmol). The reaction mixture was stirred at room ature for 40 minutes, whereupon it was treated with 4-methylmorpholine (30.8 µL, 0.280 mmol) followed by oroacetic anhydride (0.143 mL, 1.01 mmol); after 30 minutes, 4-methylmorpholine (30.8 µL, 0.280 mmol) was again added, followed by trifluoroacetic anhydride (0.143 mL, 1.01 mmol). After an additional 15 minutes of stirring, the reaction mixture was d with hydrochloric acid (1 M; 3 mL), and the resulting mixture was extracted with dichloromethane (3 x 4 mL); the combined organic layers were concentrated in vacuo and purified using reversed-phase HPLC (Waters Sunfire C18, 19 x 100 mm, 5 µm; Mobile phase A: water containing 0.05% trifluoroacetic acid (v/v); Mobile phase B: acetonitrile containing 0.05% oroacetic acid (v/v). Gradient: 20% to 60% B over 8.5 minutes, then 60% to 95% B over 0.5 minutes, then 95% B for 1 minute; Flow rate: 25 mL/minute) to afford (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane amide (13). Yield: 7.5 mg, 15 µmol, 17% over 2 steps. LCMS m/z 500.5 [M+H]+. ion time: 2.66 minutes (Analytical conditions. Column: Waters Atlantis dC18, 4.6 x 50 mm, 5 µm; Mobile phase A: 0.05% trifluoroacetic acid in water (v/v); Mobile phase B: 0.05% trifluoroacetic acid in acetonitrile (v/v); Gradient: 5.0% to 95% B over 4.0 minutes, then 95% B for 1.0 minute; Flow rate: 2 mL/minute).

Alternate Synthesis of e 13, methyl tert-butyl ether solvate; Generation of 13, methyl tert-butyl ether solvate, Solid Form 2 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide, methyl utyl ether solvate (13, methyl tert-butyl ether solvate), Solid Form 2 Step 1. Synthesis of tert-butyl 1-aminooxo[(3S)oxopyrrolidinyl]propan- 2-yl}carbamate (C5).

This experiment was carried out in 2 parallel batches. A solution of ammonia in methanol (7 M; 2.4 L, 17 mol) was added to methyl N-(tert-butoxycarbonyl)[(3S) oxopyrrolidinyl]-L-alaninate (600 g, 2.10 mol) and the reaction mixture was stirred at °C for 40 hours. Concentration in vacuo and combination of the 2 batches provided C5 as a yellow solid. Combined yield: 1.10 kg, 4.05 mol, 96%. 1H NMR (400 MHz, 6)  7.63 (br s, 1H), 7.29 (br s, 1H), 7.01 (br s, 1H), 6.89 (d, J = 8.5 Hz, 1H), 3.96 – 3.85 (m, 1H), 3.22 – 3.06 (m, 2H, assumed; partially obscured by water peak), 2.28 – 2.08 (m, 2H), 1.89 (ddd, J = 14.6, 10.8, 4.0 Hz, 1H), 1.74 – 1.60 (m, 1H), 1.56 – 1.43 (m, 1H), 1.36 (s, 9H).

Step 2. Synthesis of 3-[(3S)oxopyrrolidinyl]-L-alaninamide, hydrochloride salt (C16, HCl salt).

This experiment was carried out in 3 parallel s. To a 0 °C solution of C5 (840 g, 3.10 mol) in dichloromethane (2.0 L) was added a solution of hydrogen chloride in 1,4-dioxane (4 M; 2 L, 8 mol). The reaction mixture was stirred at 25 °C for 2 hours, whereupon it was concentrated in vacuo; combination of the 3 batches afforded C16, HCl salt as a white solid. ed yield: 1.20 kg, 5.78 mol, 62%. MS m/z 172.1 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  8.52 – 8.35 (br s, 3H), 8.12 (s, 1H), 7.95 (s, 1H), 7.57 (s, 1H), 3.88 – 3.76 (m, 1H), 3.24 – 3.10 (m, 2H), 2.59 – 2.5 (m, 1H, assumed; partially obscured by solvent peak), 2.35 – 2.24 (m, 1H), 2.01 (ddd, J = 14.9, 9.2, 6.1 Hz, 1H), 1.80 – 1.68 (m, 2H).

A sample of C16, HCl salt was triturated in 2-propanol for 1.5 hours, pon it was collected via filtration and rinsed with 2-propanol. The collected solid was dried ght under high vacuum to obtain a sample for powder X-ray diffraction study. The powder X-ray diffraction pattern for this material is given in Figure 10; characteristic peaks are listed in Table Q.

Collection of powder X-ray diffraction data The powder X-ray diffraction analysis was conducted using a Bruker AXS D4 Endeavor diffractometer equipped with a Cu ion source. The divergence slit was set at 0.6 mm while the secondary optics used variable slits. Diffracted radiation was detected by a PSD-Lynx Eye detector. The X-ray tube voltage and amperage were set to 40 kV and 40 mA respectively. Data was collected in the Theta-2Theta goniometer at the Cu ngth from 3.0 to 40.0 degrees 2-Theta using a step size of 0.020 degrees and a step time of 0.3 second. Samples were prepared by placing them in a n low background sample holder and d during collection.

The powder X-ray diffraction analysis was conducted using a Bruker AXS D8 Advance diffractometer equipped with a Cu radiation source. Diffracted radiation was detected by a LYNXEYE_EX detector with motorized slits. Both primary and secondary ed with 2.5 soller slits. The X-ray tube e and amperage were set at 40kV and 40 mA respectively. Data was collected in the Theta-Theta goniometer in a locked couple scan at Cu K-alpha (average) wavelength from 3.0 to 40.0 degrees 2-Theta with an increment of 0.02 degrees, using a scan speed of 0.5 seconds per step. Samples were prepared by placement in a silicon low background sample holder.

Data were collected with both instruments using Bruker DIFFRAC Plus software and analysis was performed by EVA DIFFRAC plus software. The PXRD data file was not processed prior to peak searching. Using the peak search algorithm in the EVA software, peaks selected with a threshold value of 1 were used to make preliminary peak assignments. To ensure validity, adjustments were manually made; the output of automated assignments was visually checked, and peak positions were adjusted to the peak maximum. Peaks with relative ity of ≥ 3% were generally chosen. Typically, the peaks which were not resolved or were consistent with noise were not selected. A typical error associated with the peak on from PXRD stated in USP up to +/- 0.2° 2- Theta (USP-941).

Table Q. Selected powder X-ray diffraction peaks for C16, HCl salt Angle (°2 theta) Rel. ity Angle (°2 theta) Rel. Intensity 9.97 3 29.24 13 11.67 1 30.98 6 14.17 1 31.78 2 16.08 1 32.32 23 16.35 1 32.79 10 17.10 14 33.10 1 17.27 3 33.50 6 18.23 24 33.70 4 19.21 4 33.90 3 .83 20 35.27 3 22.20 58 36.20 3 22.97 12 36.42 6 23.35 34 36.75 6 23.79 2 36.95 7 24.62 3 37.83 3 .10 100 38.58 2 26.85 11 39.44 7 28.39 14 39.75 1 Alternate Synthesis of 3-[(3S)oxopyrrolidinyl]-L-alaninamide, hydrochloride salt, C16 HCl salt An alternate ation of the compound C16, HCl salt is depicted in the reaction scheme below.

To a solution of ammonia in methanol (7.0 M; 100 mL, 725.4 mmol) was added methyl amino((S)oxopyrrolidinyl)propanoate 4-methylbenzenesulfonate (20 g, 55.8 mmol) and magnesium sulfate (6.7 g, 55.8 mmol) at room temperature. After stirring the reaction mixture for 7 hours at room temperature, nitrogen was bubbled into the reaction for 1 hour to purge excess ammonia. Afterwards, the reaction was filtered through a pad of Celite® and then concentrated in vacuo and the resulting (S)amino - 3-((S)oxopyrrolidinyl)propanamide 4-methylbenzenesulfonate was used directly in the subsequent step t further purification. To a solution of dimethylformamide (50 mL, 647 mmol) was added a portion of (S)amino((S)oxopyrrolidin-3 - yl)propanamide 4-methylbenzenesulfonate (10 g, 25.9 mmol) and a solution of hydrogen de in 1,4-dioxane (4.0 M; 19.4 mL, 77.7 mmol). After stirring for 12 hours at room ature the slurry was filtered and washed with dimethylformamide (15 mL, 190 mmol). The resulting solid was dried in a vacuum oven at 40 °C for 12 hours to afford 3- 2-oxopyrrolidinyl]-L-alaninamide, hydrochloride salt, C16 HCl salt (2.7 g, 12.4 mmol) as a tan solid (overall yield of 48%).

Step 3. Synthesis of methyl (1R,2S,5S)[N-(tert-butoxycarbonyl)methyl-L-valyl]-6,6- dimethylazabicyclo[3.1.0]hexanecarboxylate (C31).

This experiment was carried out in 3 parallel batches. To a 0 °C solution of methyl (1R,2S,5S)-6,6-dimethylazabicyclo[3.1.0]hexanecarboxylate, hydrochloride salt (237 g, 1.15 mol) and N-(tert-butoxycarbonyl)methyl-L-valine (293 g, 1.27 mol) in a mixture of N,N-dimethylformamide (400 mL) and acetonitrile (3.6 L) was added O-(7- azabenzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU; 481 g, 1.26 mol), followed by drop-wise addition of N,N-diisopropylethylamine (601 mL, 3.45 mol). The reaction mixture was then allowed to warm to 25 °C and was stirred for 16 hours, pon it was poured into a mixture of ice water (1 L) and hydrochloric acid (0.5 M; 1 L), of pH approximately 5, and stirred for 6 s. The resulting e was extracted with ethyl acetate (2 L), and the organic layer was washed with water (2 L), dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was purified using silica gel chromatography (Gradient: 0% to 50% ethyl acetate in petroleum ether), affording, after combination of the 3 batches, C31 as a colorless oil. ed yield: 1.17 kg, 3.06 mol, 89%. LCMS m/z 383.3 [M+H]+. 1H NMR (400 MHz, chloroform-d)  5.10 (d, J = 10.2 Hz, 1H), 4.46 (s, 1H), 4.20 (d, J = 10.3 Hz, 1H), 3.98 (d, half of AB quartet, J = 10.2 Hz, 1H), 3.89 – 3.82 (m, 1H), 3.74 (s, 3H), 1.48 – 1.41 (m, 2H), 1.38 (s, 9H), 1.03 (s, 3H), 1.01 (s, 9H), 0.89 (s, 3H).

Step 4. Synthesis of (1R,2S,5S)[N-(tert-butoxycarbonyl)methyl-L-valyl]-6,6- dimethylazabicyclo[3.1.0]hexanecarboxylic acid (C32).

This experiment was carried out in 3 el batches. To a solution of C31 (668 g, 1.75 mol) in tetrahydrofuran (2.5 L) was added m hydroxide monohydrate (220 g, 5.24 mol) and water (500 mL). After the reaction mixture had been stirred at 25 °C for 2 hours, it was concentrated in vacuo to remove most of the tetrahydrofuran; the residue was then adjusted to pH 2 by addition of 1 M hydrochloric acid. The resulting mixture was extracted with ethyl acetate (2 x 500 mL), and the combined organic layers were washed with saturated aqueous sodium chloride solution (500 mL), dried over sodium sulfate, filtered, and concentrated in vacuo to provide C32 as a white solid (2.0 kg) after combination of the 3 batches. This al was used ly in the following step. LCMS m/z 313.2 [(M − 2-methylpropene)+H]+. 1H NMR (400 MHz, form- d)  5.14 (d, J = 10.2 Hz, 1H), 4.46 (s, 1H), 4.24 (d, J = 10.2 Hz, 1H), 4.06 (d, half of AB quartet, J = 10.5 Hz, 1H), 3.82 (dd, component of ABX system, J = 10.5, 5.5 Hz, 1H), 1.75 (d, J = 7.7 Hz, 1H), 1.49 (dd, J = 7.7, 5.4 Hz, 1H), 1.40 (s, 9H), 1.06 (s, 3H), 1.00 (s, 9H), 0.89 (s, 3H).

Step 5. Synthesis of (1R,2S,5S)-6,6-dimethyl(3-methyl-L-valyl) azabicyclo[3.1.0]hexanecarboxylic acid, hydrochloride salt (C41).

This ment was carried out in 2 parallel batches. A solution of hydrogen chloride in 1,4-dioxane (4 M; 4.0 L, 16 mol) was added to a solution of C32 (from the previous step; 1.00 kg, ≤2.62 mol) in dichloromethane (1.0 L), and the reaction mixture was stirred at 25 °C for 16 hours. Removal of solvents in vacuo at 50 °C afforded C41 as a white solid (1.8 kg) after combination of the 2 batches. This material was used ly in the following step. 1H NMR (400 MHz, methanol-d 4.42 (s, 1H), 4.00 (s, 1H), 3.94 (dd, component of ABX system, J = 10.7, 5.4 Hz, 1H), 3.80 (d, half of AB quartet, J = 10.7 Hz, 1H), 1.62 (dd, ent of ABX system, J = 7.7, 5.2 Hz, 1H), 1.56 (d, half of AB t, J = 7.6 Hz, 1H), 1.15 (s, 9H), 1.09 (s, 3H), 1.03 (s, 3H).

Step 6. Synthesis of (1R,2S,5S)-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxylic acid (C42).

This experiment was carried out in 3 parallel batches. To a 0 °C solution of C41 (from the previous step; 600 g, ≤1.75 mol) in methanol (2 L) was added ylamine (1.64 L, 11.8 mol), followed by ethyl trifluoroacetate (699 g, 4.92 mol), whereupon the reaction mixture was allowed to warm to 25 °C, and was stirred for 16 hours. It was then concentrated in vacuo at 50 °C, and the residue was diluted with ethyl acetate (3 L) and adjusted to a pH of 3 to 4 by addition of 2 M hydrochloric acid. After extraction of the aqueous layer with ethyl acetate (1 L), the combined organic layers were washed with saturated s sodium de solution (3 L), dried over sodium sulfate, filtered, and concentrated under reduced pressure. The 3 batches were combined at this point, treated with a mixture of petroleum ether and ethyl acetate (5:1, 3 L), and stirred at 25 °C for 2 hours. Filtration afforded C42 as a white solid. Combined yield: 1.90 kg, 5.21 mol, 99% over 3 steps. LCMS m/z 365.1 . 1H NMR (400 MHz, methanol-d4)  8.88 (d, J = 8.8 Hz, <1H; incompletely exchanged), [4.60 (d, J = 8.9 Hz) and 4.59 (s), total 1H], 4.35 (s, 1H), 3.96 (dd, component of ABX system, J = 10.5, 5.1 Hz, 1H), 3.90 (d, half of AB quartet, J = 10.4 Hz, 1H), 1.58 (dd, component of ABX system, J = 7.6, 4.9 Hz, 1H), 1.52 (d, half of AB t, J = 7.6 Hz, 1H), 1.08 (s, 12H), 0.92 (s, 3H).

Step 7. Synthesis of (1R,2S,5S)-N-{(2S)aminooxo[(3S)oxopyrrolidin yl]propanyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide (C43).

This experiment was carried out in 4 parallel batches. 2-Hydroxypyridine 1-oxide (33.9 g, 305 mmol) was added to a solution of C42 (445 g, 1.22 mol) and C16, HCl salt (256 g, 1.23 mol) in butanone (2.5 L), and the mixture was cooled to 0 °C. N,N- ropylethylamine (638 mL, 3.66 mol) was then added, followed by ise addition of 1-[3-(dimethylamino)propyl]ethylcarbodiimide hloride (351 g, 1.83 mol). The reaction mixture was stirred at 25 °C for 16 hours, whereupon it was diluted with ethyl acetate (1 L) and treated with a mixture of hydrochloric acid (1 M; 1.5 L, 1.5 mol) and saturated aqueous sodium chloride solution (1 L). The organic layer was washed with a mixture of aqueous sodium hydroxide solution (1 M; 1.5 L, 1.5 mol) and saturated aqueous sodium chloride solution (1 L), dried over sodium sulfate, filtered, and concentrated in vacuo. Combination of the 4 batches provided C43 as a white solid (2.3 kg). Combined yield: 2.1 kg (corrected for residual ethyl acetate), 4.1 mol, 84%.

LCMS m/z 518.3 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  9.41 (br d, J = 7.7 Hz, 1H), 8.30 (d, J = 8.8 Hz, 1H), 7.56 (s, 1H), 7.32 (br s, 1H), 7.04 (br s, 1H), 4.43 (br d, J = 7.3 Hz, 1H), 4.35 – 4.25 (m, 1H), 4.28 (s, 1H), 3.89 (dd, J = 10.3, 5.5 Hz, 1H), 3.67 (d, J = .4 Hz, 1H), 3.17 – 3.09 (m, 1H), 3.07 – 2.98 (m, 1H), 2.46 – 2.35 (m, 1H), 2.19 – 2.10 (m, 1H), 1.99 – 1.89 (m, 1H), 1.70 – 1.58 (m, 1H), 1.55 – 1.44 (m, 2H), 1.38 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.01 (s, 3H), 0.98 (s, 9H), 0.84 (s, 3H).

Step 8. sis of (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide, methyl utyl ether solvate (13, methyl tert-butyl ether solvate), Solid Form 2.

This experiment was carried out in 3 parallel batches. Methyl N- (triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 552 g, 2.32 mol) was added to a solution of C43 (600 g, 1.16 mol) in ethyl acetate (3 L). After the reaction mixture had been stirred at 25 °C for 3 hours, it was treated with additional methyl N- (triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 27.6 g, 116 mmol) and the reaction mixture was stirred for 1 hour. It was then filtered; the filter cake was washed with ethyl acetate (2 x 500 mL), and the combined filtrates were washed tially with aqueous sodium bicarbonate solution (1 M; 2 L), saturated aqueous sodium de solution (2 L), hydrochloric acid (1 M; 2 L), and ted aqueous sodium chloride solution (2 L). The organic layer was then dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was d with a mixture of ethyl acetate and methyl tert-butyl ether (1:10, 2.5 L) and heated to 50 °C; after stirring for 1 hour at 50 °C, it was cooled to 25 °C and d for 2 hours. The solid was collected via filtration, and the 3 batches were combined in ethyl acetate (8 L) and ed through silica gel (3.0 kg); the silica gel was then washed with ethyl acetate (2 x 2 L). After the ed eluates had been concentrated in vacuo, the residue was taken up in ethyl acetate (900 mL) and methyl tert-butyl ether (9 L). This mixture was heated to 50 °C for 1 hour, cooled to 25 °C, and stirred for 2 hours. Filtration afforded (1R,2S,5S)-N-{(1S)- 1-cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L- valyl]azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl ether solvate (13, methyl tert-butyl ether solvate) as a white solid. The powder X-ray diffraction pattern for this material, designated as Solid Form 2, is given in Figure 1; characteristic peaks are listed in Table A. Combined yield: 1.41 kg, 2.82 mol, 81%. LCMS m/z 500.3 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  9.42 (d, J = 8.4 Hz, 1H), 9.03 (d, J = 8.6 Hz, 1H), 7.68 (s, 1H), 4.97 (ddd, J = 10.9, 8.5, 5.1 Hz, 1H), 4.41 (d, J = 8.5 Hz, 1H), 4.16 (s, 1H), 3.91 (dd, J = 10.4, 5.5 Hz, 1H), 3.69 (d, J = 10.4 Hz, 1H), 3.18 – 3.10 (m, 1H), 3.08 – 2.99 (m, 1H), 2.46 – 2.34 (m, 1H), 2.20 – 2.03 (m, 2H), 1.78 – 1.65 (m, 2H), 1.57 (dd, J = 7.6, 5.4 Hz, 1H), 1.32 (d, J = 7.6 Hz, 1H), 1.03 (s, 3H), 0.98 (s, 9H), 0.85 (s, 3H).

Collection of powder X-ray diffraction data Powder X-ray ction analysis was conducted using a Bruker AXS D8 Endeavor diffractometer equipped with a Cu radiation source (K-α average). The divergence slit was set at 15 mm continuous illumination. cted radiation was detected by a PSD-Lynx Eye detector, with the detector PSD opening set at 2.99 degrees. The X-ray tube voltage and amperage were set to 40 kV and 40 mA respectively. Data was collected in the Theta-Theta goniometer at the Cu wavelength from 3.0 to 40.0 degrees 2-Theta using a step size of 8 degrees and a step time of 1.0 second. The antiscatter screen was set to a fixed distance of 1.5 mm. Samples were rotated at 15/minute during tion. Samples were prepared by placing them in a silicon low-background sample holder and rotated during tion. Data were collected using Bruker DIFFRAC Plus software and analysis was performed by EVA DIFFRAC Plus software. Using the peak search algorithm in the EVA software, peaks selected with a old value of 1 were used to make preliminary peak ments. To ensure validity, adjustments were manually made; the output of automated assignments was visually checked and peak ons were adjusted to the peak maximum. Peaks with relative intensity of ≥ 3% were generally chosen. The peaks which were not resolved or were consistent with noise were not selected. A typical error associated with the peak on from PXRD stated in USP is up to +/- 0.2° 2-Theta (USP-941).

Table A. Selected powder X-ray diffraction peaks for 13, methyl tert-butyl ether solvate, Solid Form 2, from Alternate Synthesis of Example 13, methyl tert-butyl ether solvate; Generation of 13, methyl tert-butyl ether solvate, Solid Form 2 Angle Relative Angle Relative (°2-theta) Intensity (%) (°2-theta) Intensity (%) +/- 0.2° 2-Theta +/- 0.2° 2-Theta 7.1 78 22.7 9 .5 8 22.9 10 11.3 15 23.1 5 11.8 36 23.4 6 12.5 49 23.7 22 12.9 4 25.3 14 14.2 34 27.3 3 .7 10 27.9 6 16.0 24 28.3 9 16.8 100 28.5 4 17.0 41 29.1 3 18.5 50 29.4 6 18.8 7 30.2 3 19.1 25 30.8 5 19.9 11 32.0 4 .2 8 33.3 7 .8 14 33.8 4 21.1 9 35.4 7 21.4 4 36.4 6 21.7 4 38.1 3 22.2 24 Alternate Synthesis of (1R,2S,5S)-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxylic acid (C42).

Second Alternate Synthesis of Example 13, methyl tert-butyl ether e; Generation of 13, methyl tert-butyl ether solvate, Solid Form 2 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl ether solvate (13, methyl utyl ether solvate), Solid Form 2 Methyl N-(triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 392 g, 1.64 mol) was added to a solution of C43 (415 g, 802 mmol) in ethyl acetate (2.0 L).

The reaction mixture was d at 25 °C for 3 hours, whereupon methyl N- (triethylammoniosulfonyl)carbamate, inner salt (Burgess reagent; 86.0 g, 361 mmol) was again added. After the reaction mixture had been d for 1 hour, it was filtered, and the filtrate was washed sequentially with aqueous sodium bicarbonate solution (1 M; 1.5 L), saturated aqueous sodium chloride solution (1.5 L), hydrochloric acid (1 M; 1.5 L), and saturated aqueous sodium chloride solution (1.5 L), dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was treated with a mixture of ethyl acetate and methyl utyl ether (1:10, 2.5 L) and heated to 50 °C; after stirring for 1 hour at 50 °C, it was cooled to 25 °C and d for 2 hours. Collection of the solid via tion afforded (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6- dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide, methyl tert-butyl ether solvate (13, methyl tert-butyl ether solvate) as a crystalline white solid. The powder X-ray diffraction pattern for this material, designated as Solid Form 2, is given in Figure 2; characteristic peaks are listed in Table B. Yield: 338 g, 575 mmol, 72%. LCMS m/z 500.3 [M+H]+. 1H NMR (400 MHz, DMSO-d 6)  9.43 (d, J = 8.4 Hz, 1H), 9.04 (d, J = 8.6 Hz, 1H), 7.68 (s, 1H), 4.97 (ddd, J = 10.9, 8.5, 5.0 Hz, 1H), 4.41 (d, J = 8.5 Hz, 1H), 4.15 (s, 1H), 3.91 (dd, component of ABX , J = .4, 5.5 Hz, 1H), 3.69 (d, half of AB quartet, J = 10.4 Hz, 1H), 3.18 – 3.10 (m, 1H), 3.08 – 2.98 (m, 1H), 2.46 – 2.34 (m, 1H), 2.20 – 2.02 (m, 2H), 1.77 – 1.65 (m, 2H), 1.57 (dd, J = 7.6, 5.4 Hz, 1H), 1.32 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.02 (s, 3H), 0.98 (s, 9H), 0.85 (s, 3H); methyl tert-butyl ether peaks: 3.07 (s, 3H), 1.10 (s, 9H).

The method of collection of the powder X-ray diffraction data is described in Alternate Synthesis of Example 13, methyl tert-butyl ether solvate, Step 8.

Table B. Selected powder X-ray diffraction peaks for 13, methyl tert-butyl ether solvate, Solid Form 2, from Second Alternate Synthesis of Example 13, methyl tert- butyl ether solvate; Generation of 13, methyl tert-butyl ether solvate, Solid Form 2 Angle Angle Relative Angle Relative Relative (°2-theta) (°2-theta) Intensity (°2-theta) Intensity Intensity +/- 0.2° +/- 0.2° (%) +/- 0.2° (%) (%) 2-Theta 2-Theta a 7.2 66 20.0 9 27.4 3 .6 9 20.3 6 28.0 6 11.4 12 20.8 6 28.4 7 11.9 32 20.9 12 29.5 4 12.6 49 21.2 7 30.3 3 13.0 4 21.5 4 30.9 5 14.3 37 21.8 3 32.1 3 .8 8 22.3 24 33.4 5 16.1 22 22.8 6 33.5 3 16.9 100 23.0 9 35.5 6 17.2 46 23.2 5 36.5 3 18.6 42 23.5 6 38.2 3 18.9 6 23.8 17 19.3 23 25.4 10 Third Alternate sis of Example 13 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (13) Step 1. Synthesis of (1R,2S,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}- 6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide, methyl tert-butyl ether e (13, methyl tert-butyl ether e) A 0 °C e of C42 (90.5 mass%, 5.05 g, 12.5 mmol) and C16, HCl salt (98.9 mass%, 3.12 g, 14.9 mmol) in acetonitrile (50 mL) was treated with 2,4,6-tripropyl- 1,3,5,2,4,6-trioxatriphosphinane 2,4,6-trioxide (50% solution by weight in acetonitrile; 17 mL, 24.3 mmol) over approximately 10 minutes. 1 -Methyl-1H-imidazole (4.0 mL, 50.2 mmol) was then added slowly, over approximately 15 minutes, and the reaction mixture was allowed to stir at 0 °C for 3.5 hours, whereupon it was warmed to 25 °C. 2,4,6- Tripropyl-1,3,5,2,4,6-trioxatriphosphinane 2,4,6-trioxide (50% solution by weight in acetonitrile; 17 mL, 24.3 mmol) was added in one portion, and the reaction mixture was d at 45 °C for 16 hours. It was cooled to 25 °C at that point, and then treated over 10 minutes with an aqueous solution of sodium bicarbonate (1.14 M; 35 mL, 40 mmol).

After addition of ethyl acetate (25 mL) and sufficient water to dissolve the resulting solids, the organic layer was washed twice with an aqueous solution of sodium bicarbonate (1.14 M; 25 mL, 28 mmol). After the organic layer had been washed with aqueous sodium de solution (14%, 2 x 20 mL), it was dried over sodium sulfate, filtered, and concentrated in vacuo. The e was mixed with ethyl acetate (2.1 mL) and treated with methyl tert-butyl ether (19 mL); the resulting slurry was heated with stirring at 50 °C for 1 hour, cooled to 25 °C over 1 hour, and held at 25 °C for 1.5 hours.

Solids were isolated via filtration, washed with methyl tert-butyl ether (2 mL/g), and dried in a vacuum oven overnight at 50 °C to afford (1R,2S,5S)-N-{(1S)cyano [(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide, methyl tert-butyl ether solvate (13, methyl tert-butyl ether solvate) as a crystalline white solid. The bulk of this material was progressed to the following step. Yield: 3.71 g, 6.31 mmol, 50%. 1H NMR (400 MHz, DMSO-d6)  9.40 (d, J = 8.4 Hz, 1H), 9.02 (d, J = 8.6 Hz, 1H), 7.66 (s, 1H), 4.97 (ddd, J = 10.7, 8.6, 5.1 Hz, 1H), 4.41 (d, J = 8.4 Hz, 1H), 4.16 (s, 1H), 3.91 (dd, component of ABX system, J = 10.3, 5.5 Hz, 1H), 3.69 (d, half of AB quartet, J = 10.4 Hz, 1H), 3.18 – 3.10 (m, 1H), 3.09 – 2.99 (m, 1H), 2.46 – 2.35 (m, 1H), 2.20 – 2.04 (m, 2H), 1.78 – 1.64 (m, 2H), 1.56 (dd, J = 7.4, 5.6 Hz, 1H), 1.32 (d, half of AB quartet, J = 7.6 Hz, 1H), 1.03 (s, 3H), 0.98 (s, 9H), 0.85 (s, 3H); methyl tert-butyl ether peaks: 3.07 (s, 3H), 1.10 (s, Step 2. Synthesis of ,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}- 6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexane carboxamide (13).

A mixture of propan yl acetate (17 mL) and heptane (17 mL) was added to 13, methyl tert-butyl ether solvate (from the previous step; 3.41 g, 5.80 mmol), and stirring was carried out overnight at 20 °C. Heptane (17 mL) was then added over 2 hours, and the e was stirred overnight at room temperature. The resulting slurry was filtered, and the ted solids were washed with a mixture of propanyl acetate (1.36 mL) and heptane (3.73 mL) and dried at 50 °C under vacuum, ing ,5S)-N-{(1S)cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl- N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (13) as a crystalline solid. A portion of this batch was used as seed material in Recrystallization of Example 13; Generation of Solid Form 1 below. Yield: 2.73 g, 5.46 mmol, 94%.

Recrystallization of Example 13; Generation of Solid Form 1 (1R,2S,5S)-N-{(1S)Cyano[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3- methyl-N-(trifluoroacetyl)-L-valyl]azabicyclo[3.1.0]hexanecarboxamide (13), Solid Form 1 A mixture of 13, methyl tert-butyl ether solvate (from Alternate Synthesis of e 13, methyl tert-butyl ether solvate; Generation of 13, methyl tert-butyl ether solvate, Solid Form 2; 60.1 g, 102 mmol) and propan yl acetate (480 mL) was heated to 60 °C. A sample of 13 (seed material, from Third Alternate Synthesis of e 13, Step 2; 1.2 g, 2.4 mmol) was added; after 10 minutes, the seed material was still present in solid form. Heptane (360 mL) was slowly added to the stirring mixture, over 12 hours. Additional heptane (360 mL) was introduced over 4 hours, and the resulting mixture was stirred for 30 minutes. It was then cooled to 20 °C, at a rate of 0.1 degrees/minute, whereupon it was stirred overnight. The solid was ted via filtration, and washed with a mixture of propan yl acetate (72 mL) and heptane (168 mL). It was then dried under vacuum at 50 °C to provide (1R,2S,5S)-N-{(1S)cyano- 2-[(3S)oxopyrrolidinyl]ethyl}-6,6-dimethyl[3-methyl-N-(trifluoroacetyl)-L-valyl] azabicyclo[3.1.0]hexanecarboxamide (13) as a white, crystalline solid. The powder X-ray ction pattern for this material, designated as Solid Form 1, is given in Figure 3; characteristic peaks are listed in Table C. Yield: 47.8 g, 95.7 mmol, 94%.

The method of tion of the powder X-ray ction data is described in Alternate Synthesis of Example 13, methyl tert-butyl ether solvate, Step 8.

Table C. Selected powder X-ray diffraction peaks for 13, Solid Form 1 Angle Relative Angle Relative Angle Relative (°2-theta) Intensity (%) (°2-theta) Intensity (%) (°2-theta) Intensity (%) +/- 0.2° +/- 0.2° +/- 0.2° 2-Theta 2-Theta 2-Theta 7.6 16 18.9 11 24.7 8 9.8 10 19.7 7 25.3 7 11.4 10 19.9 14 27.0 3 11.9 13 20.5 36 27.2 6 12.7 100 21.0 14 27.9 4 .7 40 21.7 4 28.1 3 .8 18 22.2 23 29.5 7 17.3 10 22.5 3 32.6 6 17.8 12 23.1 6 35.7 4 18.3 55 23.6 10 37.0 3 Single-crystal X-ray Structural Determination of Example 13, Solid Form 1 A sample of Example 13 was subjected to crystallization via diffusion, using ethyl acetate and . The crystallization vessel was allowed to stand at room temperature while the solvent evaporated; after 2.5 , crystals of X-ray quality were present. One of these was used for the ural determination. An ORTEP diagram of the single-crystal data is shown in Figure 4. y software was used to calculate the powder pattern from the ed crystal structure; comparison with the diffraction pattern from Recrystallization of Example 13; Generation of Solid Form 1 identified this material as being Solid Form 1 (see Figure 5). Characteristic peaks for this calculated data are provided in Table D.

Table D. Powder pattern data for 13, Solid Form 1 calculated from Single-crystal X-ray Structural Determination of Example 13, Solid Form 1 Angle Angle Angle (°2-theta) Relative (°2-theta) Relative (°2-theta) ve +/- 0.2° Intensity (%) +/- 0.2° Intensity (%) +/- 0.2° Intensity (%) 2-Theta 2-Theta 2-Theta 7.6 22 21.0 28 30.1 4 9.8 21 21.6 14 30.3 3 .4 9 21.7 14 31.5 4 .8 4 22.2 40 31.7 5 11.4 16 22.5 7 31.9 4 11.9 75 23.1 5 32.7 8 12.7 89 23.6 15 33.4 3 14.6 3 24.3 5 33.6 8 .7 100 24.8 15 35.7 8 .9 30 25.4 10 36.6 3 17.4 34 26.4 3 36.6 3 17.9 24 27.0 9 37.0 4 18.3 67 27.3 8 37.3 4 18.9 12 27.9 3 38.3 3 19.7 15 28.1 5 39.4 3 19.9 63 28.7 5 39.6 4 .5 53 29.5 9 .8 9 30.0 9 Single Crystal X-Ray Analysis Data collection was performed on a Bruker D8 Quest diffractometer at room ature. Data collection consisted of omega and phi scans.

The ure was solved by intrinsic phasing using SHELX software suite in the orthorhombic class space group P212121. The structure was subsequently d by the full-matrix least s method. All non-hydrogen atoms were found and refined using anisotropic displacement parameters.

The hydrogen atoms located on nitrogen were found from the Fourier difference map and refined with distances restrained. The remaining hydrogen atoms were placed in calculated positions and were allowed to ride on their carrier atoms. The final refinement included isotropic displacement parameters for all hydrogen atoms.

Analysis of the absolute structure using likelihood methods (Hooft, 2008) was performed using PLATON (Spek). The s indicate that the absolute structure has been correctly assigned. The method calculates that the probability that the structure is correctly assigned is 100%. The Hooft parameter is ed as −0.01 with an esd (estimated rd deviation) of (3) and the Parson’s parameter is reported as −0.01 with an esd of (2).

The final R-index was 3.3%. A final difference Fourier revealed no missing or misplaced electron density.

Pertinent crystal, data collection, and refinement information is summarized in Table E. Atomic coordinates, bond lengths, bond angles, and cement ters are listed in Tables F – H.

Software and References SHELXTL, Version 5.1, Bruker AXS, 1997.

PLATON, A. L. Spek, J. Appl. Cryst. 2003, 36, 7–13.

MERCURY, C. F. Macrae, P. R. Edington, P. McCabe, E. Pidcock, G. P. Shields, R. Taylor, M. Towler, and J. van de Streek, J. Appl. Cryst. 2006, 39, 453–457.

OLEX2, O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. , and H. Puschmann, J. Appl. Cryst. 2009, 42, 339–341.

R. W. W. Hooft, L. H. Straver, and A. L. Spek, J. Appl. Cryst. 2008, 41, 96–103.

H. D. Flack, Acta Cryst. 1983, A39, 867–881.

Table E. Crystal data and structure refinement for Example 13, Solid Form 1. _______________________________________________________________ Empirical formula C23H32F3N5O4 Formula weight 499.53 Temperature 296(2) K Wavelength 1.54178 Å Crystal system Orthorhombic Space group P212121 Unit cell ions a = 9.6836(2) Å α = 90° b = 2(4) Å β = 90° c = 18.0272(5) Å γ = 90° Volume 2627.64(11) Å3 Z 4 Density lated) 1.263 Mg/m3 Absorption coefficient 0.862 mm−1 F(000) 1056 Crystal size 0.300 x 0.280 x 0.260 mm3 Theta range for data collection 3.826 to 80.042° Index ranges −12<=h<=12, <=19, −22<=l<=23 tions collected 79731 Independent reflections 5628 [Rint = 0.0294] Completeness to theta = 67.679° 99.3% Absorption correction Empirical ment method Full-matrix least-squares on F2 Data / restraints / parameters