ANTIVIRAL SUBSTANCES WITH A WIDE SPECTRUM OF ACTIVITY

Abstract

A substance of the formula (1) and its use as an antiviral active substance.

##STR00001##

Claims

1. A substance of the following formula: ##STR00019## wherein A may be the same or different and is selected from the group consisting of N and CR.sup.8 wherein R.sup.8 is selected from the group consisting of H, F, Cl and Br, R.sup.1 may be the same or different and is selected from the group consisting of H, alkyl, C(O)OR.sup.5 wherein R.sup.5 can be branched or unbranched alkyl, cycloalkyl, substituted or unsubstituted aryl, heteroaryl, arylalkyl, aryloxy, heteroalkyloxy, arylalkoxy, heteroalkylalkoxy; and C(O)NHR.sup.6 wherein R.sup.6 can be branched or unbranched alkyl, cycloalkyl, substituted or unsubstituted aryl, heteroaryl, arylalkyl, aryloxy, heteroalkyloxy, arylalkoxy, heteroalkylalkoxy and SO.sub.2R.sup.7 wherein R.sup.7 can be branched or unbranched alkyl, cycloalkyl, substituted or unsubstituted aryl, heteroaryl, arylalkyl, aryloxy, heteroalkyloxy, arylalkoxy, heteroalkylalkoxy, R.sup.2 is selected from the group consisting of branched or unbranched alkyl, cycloalkyl, cycloalkylmethyl, cycloalkylethyl, cycloalkylpropyl, substituted or unsubstituted aryl, heteroaryl, arylalkyl, aryloxy, heteroalkyloxy, arylalkoxy, heteroalkylalkoxy, and branched or unbranched amino acids, R.sup.3 is selected from the group consisting of H, branched or unbranched alkyl, cycloalkyl, cycloalkylmethyl, cycloalkylethyl, cycloalkylpropyl, aryl, heteroaryl, arylmethyl, heteroarylmethyl, and R.sup.4 is selected from the group consisting of ##STR00020## and/or its salts, adducts, tautomers and/or solvates.

2. The substance according to claim 1 of the following formula: ##STR00021## and/or its salts, adducts, tautomers and/or solvates.

3. The substance according to claim 1, wherein it is selected from the group consisting of: ##STR00022## ##STR00023## and/or salts, adducts, tautomers, diastereomers and/or solvates of these substances.

4. The substance according to claim 1, wherein it acts on 3C- or 3C-like (3CL)-proteases of RNA viruses.

5. The substance according to claim 1, wherein it acts on the 3CL protease of the coronavirus SARS-CoV-2.

6. The substance according to claim 1, wherein it has a half-life in plasma of more than 30 minutes.

7. The substance according to claim 1, wherein it exhibits lung entropism.

8. A medicine comprising the substance according to claim 1 in a pharmaceutically acceptable carrier.

9. A method for treatment of a disease comprising administering to a patient in need thereof a substance according to claim 1.

10. The method according to claim 9, wherein the disease is caused by RNA viruses.

11. The method according to claim 9, characterized in that wherein the disease is caused by at least one of coronaviruses, picornaviruses, enteroviruses and noroviruses.

12. The method according to claim 9, characterized in that wherein the disease is caused by SARS-CoV-2.

13. The substance according to claim 1, wherein it has a half-life in plasma of more than 40 minutes

14. The substance according to claim 1, wherein it has a half-life in plasma of more than 44 minutes.

Description

LIST OF FIGURES

[0029] FIG. 1: Complexation of SARS-CoV MP″ by RHCDS1e.

[0030] FIG. 2: Complexation of CVB3 3CP″ by RHCDS1e.

[0031] FIG. 3: Complexation of MERS-CoV MP″ by RHCDS1c.

[0032] FIG. 4: Complexation of the 3CL protease of coronavirus SARS-CoV-2 MP″ by RHCDS1c.

[0033] FIG. 5: Pharmacokinetic studies in mice with RHCDS1e.

[0034] FIG. 6: Pharmacokinetic studies in mice with RHCDS1e.

[0035] FIG. 1 shows the complexation of SARS coronavirus protease (SARS-CoV M.sup.pro) by the drug

[0036] RHCD1e based on crystallographic studies.

[0037] FIG. 2 shows the complexation of coxsackievirus B3CVB3 3C protease.sup.pro by RHCDS1e.

[0038] FIG. 3 shows the complexation of MERS coronavirus protease MERS-CoV MP.sup.pro by RHCDS1c.

[0039] FIG. 4 shows the complexation of 3CL protease of coronavirus SARS-CoV-2 MP″ by RHCDS1c.

[0040] The activity of the compounds of the invention compared to the lead compound DZLO8 is particularly good for betacoronavirus proteases (SARS-CoV Mpro, MERS-CoV Mpro, SARS-CoV-2 Mpro). For example, the compound RHCDS1c showed IC50 values of 0.90 uM, 0.58 uM, and 0.67 uM against these proteases (measured by inhibition of cleavage of a standard substrate by the compound in a fluorescence-based assay). These values are slightly improved compared to those obtained with the lead compound DZL08.

[0041] The bioavailability of the lead compound DZLO8 was also characterized in detail in an external CRO- study and the results verified.

[0042] Pharmacokinetic studies show that the compound RHCDS1e according to the invention has a 50% improved half-life of (t.sub.1/2=0.45±0.1 h) compared to the lead compound DZLO8 (t.sub.1/2=0.33 ±0.0 h). Stabilization of the P3-P2 amide bond according to the invention also reduced the high plasma protein binding compared to DZLO8 (99%) to 94%.

[0043] Table 3 below shows pharmacokinetic data of compound RHCDS1e compared to lead compound DZL08.

TABLE-US-00003 TABLE 3 Pharmacokinetic data of RHCDS1e compared to DZL08. DZL08 2 mg/kg i.v. RHCDS1e 2 mg/kg i.v. t1/2 [h] 0.33 ± 0.0 0.45 ± 0.1 V [l/kg] 8.20 ± 4.1 6.73 ± 0.4 CL [ml/min/kg] 292.43 ± 162.0 177.66 ± 51.2  AUC 0-t [ng/ml * h] 134.65 ± 74.6  193.22 ± 59.0  MRI [h] 0.48 ± 0.0 0.47 ± 0.1 CO [ng/ml] 278.34 ± 138.5 461.44 ± 345.0

[0044] Furthermore, RHCDS1e shows good metabolic stability in mouse and human microsomes. After 30 minutes, 80% of the compound remained metabolically stable in mouse microsomes and 60% in the case of human microsomes. No evidence of toxicity in mice was observed. Pharmacokinetic studies after subcutaneous injection of RHCDS1e in CD-1 mice (20 mg/kg) showed that the compound remained in plasma for only about 4 hours but was excreted in urine for up to 24 hours. The Cmax was 334.50 ng/ml and the mean residence time was approximately 1.59 hours. This can also be seen in FIG. 5 and FIG. 6. Although RHCDS1e disappears from plasma very rapidly, the compound was found at a concentration of 135 ng per g tissue in the lung and 52.7 ng/ml broncheoalveolar washing fluid (BALF) after 24 hours, suggesting a major distribution in the tissue. Given the current coronavirus outbreak, it is advantageous to have agents with pronounced lung tropism.

##STR00016## ##STR00017## ##STR00018##

[0045] Reaction conditions: (a) NaNO.sub.2, H.sub.2SO.sub.4, H.sub.2O; (b) SOCl.sub.2, MeOH; (c) Tf.sub.2O, 2,6-lutidine, CH.sub.2Cl.sub.2; (d) NaH, THF; (e) LiOH, MeOH, H.sub.2O; (f) HOBT, EDCI, CH.sub.2Cl.sub.2; (g) NaBH.sub.4, MeOH; (h) DMP, NaHCO.sub.3, CH.sub.2Cl.sub.2; (i) isocyanide, AcOH, CH.sub.2Cl.sub.2; (j) LiOH, MeOH, H.sub.2O; (k) DMP, NaHCO.sub.3, CH.sub.2Cl.sub.2; (1) 4 M HCl, EA

[0046] In a further aspect of the invention, the agent according to the invention can be used in medicine for therapy of a disease. In particular, for therapy of a disease caused by RNA viruses. Very particularly for therapy of a disease caused by coronaviruses, picornaviruses, including enteroviruses and/or noroviruses.

[0047] The active ingredient according to the invention can be supplied in the form of a pharmaceutical preparation.

[0048] Such preparations are generally known to the skilled person. In particular, such pharmaceutical preparations and dosage forms are described in US 10,189,810 B2.

Material and Methods

[0049] In the following, not limiting the generality of the teachings, the exemplary preparation of the compounds according to the invention will be described.

General Procedure

[0050] The reagents and reactants used were obtained commercially from commercial sources known to the skilled person and were used without further pretreatment.

[0051] HSGF 254 silica gel plates (thickness 0.15-0.2 mm) were used for thin layer chromatography (DC).

[0052] All products were characterized by NMR and mass spectroscopy (MS).

[0053] .sup.1H-NMR was measured at 300 MHz, chemical shift (δ) is given in ppm, tetramethylsilane was used as standard. The coupling of the protons is characterized as singlet (s), doublet (d), triplet (t), multiplet (m), and broad (br).

[0054] A Bruker ESI ion-trap HCT Ultra was used for the MS.

[0055] HPLC data were collected using an LC20A (Shimadzu Corporation). Columns: GIST C18 (5 μm, 4.6×150 mm) ternary solvent system (methanol/water, methanol/ 0.1% HCOOH in water, or methanol1/0.1% ammonia in water). Purity was determined by reversed-phase HPLC and was ≥95% for all samples.

Synthesis of Compound 1

[0056] A solution of (R)-2-amino-3-cyclopropylpropanoic acid or (R)-2-amino-3-cyclohexylpropanoic acid (7.74 mmol) in 2N H2504 (15 ml) is stirred at 0° C. Then dropwise NaNO2 (5.34 g, 77.4 mmol) in H.sub.2O (6 ml) is added. The solution is stirred at 0° C. for 3 h and then brought to 20° C. and stirred for 16 h at 20° C. The mixture is extracted with MTBE (50 ml). The organic phase is then dried over anhydrous Na.sub.2SO.sub.4 under vacuum. (Yield of compound 1: 50-75%, colorless oil).

Synthesis of Compound 2

[0057] SOCl.sub.2 (0.8 mL, 11.34 mmol) is added dropwise to a solution of compound 1 (5.72 mmol) in

[0058] MeOH (20 ml) at 0° C. The mixture is then stirred for 1.5 h at 20° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (PE/EA=1/1). (Yield of compound 2: 30-59%, colorless oil).

Methyl (R)-3-Cyclopropyl-2-Hydroxypropanoate 2a

[0059] .sup.1H NMR (300 MHz, CDC1.sub.3) 6 4.35 (dd, J.sub.1=9.0 Hz, J.sub.2=4.2 Hz, 1 H), 3.80 (s, 3 H), 1.81-1.72 (m, 2 H), 0.92-0.68 (m, 1 H), 0.50-0.43 (m, 2 H), 0.15-0.05 (m, 2 H).

Methyl (R)-3-Cyclohexyl-2-Hydroxypropanoate 2b

[0060] .sup.1H NMR (300 MHz, CDCl .sub.3) δ4.39-4.34 (m, 1 H), 3.82 (s, 3 H), 1.82-1.48 (m, 8 H), 1.29-1.12 (m, 4 H), 1.00-0.85 (m, 2 H).

Synthesis of Compound 3

[0061] Compound 2 (5.32 mmol) is dissolved in DCM (10 mL) and cooled to 0° C. Portionwise, 2,6-lutidine (1.5 ml, 13.26 mmol) and Tf20 (3.3 g, 11.87 mmol) are added. The mixture is stirred at 0° C. for 30 min. The mixture is washed with saline and 1N HCl (3:1 v/v) and then extracted with MTBE and dried with anhydrous Na.sub.2SO.sub.4 under vacuum. (Yield of compound 3: 82%, brown oil).

Synthesis of Compound 5

[0062] Tert-butyl (2-oxo-1,2-dihydropyridin-3-yl)carbamate (379 mg, 1.8 mmol) is dissolved in THF (15 ml). The NaH (115 mg, 2.80 mmol, 60% in oil) is added at 0° C. and then stirred for 30 min. Compound 3 (515 mg, 1.86 mmol) in THF (10 ml) is added. The mixture is stirred for 20 hat 25° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (PE/EA). (Yield of compound 5: 56-60%, light yellow solid).

Methyl (S)-2-(3-((Tert-Butoxycarbonyl)Amino)-2-Oxopyridin-1(2 H)-yl)-3-Cyclopropylpropanoate 5a

[0063] .sup.1H NMR (300 MHz, DMSO-d.sub.6) δ7.83-7.78 (m, 2 H), 7.35 (dd, J.sub.1=7.2 Hz, J.sub.2=1.5 Hz, 1 H), 6.30 (t, J=7.2 Hz, 1 H), 5.36 (dd, J.sub.1=10.8 Hz, J.sub.2=4.5 Hz, 1 H), 3.57 (s, 3 H), 1.81-1.62 (m, 2 H), 1.48 (s, 9 H), 0.55-0.48 (m, 1 H), 0.34-0.29 (m, 2 H), 0.15-0.12 (m, 1 H), 0.04-0.01 (m, 1 H). ESI-MS (m/z): 337 [M +H].sup.+.

Methyl (5)-2-(3-((Tert-Butoxycarbonyl)amino)-2-Oxopyridin-1(2 H)-yl)-3-Cyclohexylpropanoate 5b

[0064] .sup.1H NMR (300 MHz, DMSO-d6) δ7.82-7.76 (m, 2 H), 7.35 (dd, J.sub.1=7.5 Hz, J.sub.2=1.5 Hz, 1 H), 6.30 (t, J =7.5 Hz, 1 H), 5.35 (dd, J.sub.1=11.1 Hz, J.sub.2=4.5 Hz, 1 H), 3.56 (s, 3 H), 2.10-1.88 (m, 2 H), 1.78-1.72 (m, 1 H), 1.65-1.44 (m, 13 H), 1.14-0.82 (m, 6 H). ESI-MS (m/z): 379 [M +H].sup.+.

Synthesis of Compound 6

[0065] To compound 5 (1.65 mmol) in MeOH (15 ml) and H.sub.2O (3 ml) is added LiOH.H20 (139 mg, 3.31 mmol). The mixture is stirred for 1 h at 20° C. A pH=6˜7 is adjusted with 1 N HC1. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH =10/1) (yield of compound 6: 452 mg, 84%, pale yellow solid).

(S)-2-(3-((Tert-Butoxycarbonyl)Amino)-2-Oxopyridin-1(2 H)-Yl)-3-Cyclopropylpropanoic Acid 6a

[0066] .sup.1H NMR (300 MHz, DMSO-d6) 6 13.11(s, 1 H), 7.81-7.77 (m, 2 H), 7.36 (dd, J.sub.1=6.9 Hz, J.sub.2=1.5 Hz, 1 H), 6.30 (t, J=6.9 Hz, 1 H), 5.35 (dd, J.sub.1=10.5 Hz, J.sub.2=4.5 Hz, 1 H), 1.80-1.69 (m, 2 H), 1.47 (s, 9 H), 0.53-0.48 (m, 1 H), 0.32-0.29 (m, 2 H), 0.14-0.11 (m, 1 H), 0.03-0.00 (m, 1 H). ESI-MS (m/z): 323 [M +H].sup.+.

(S)-2-(3-((Tert-Butoxycarbonyl)Amino)-2-Oxopyridin-1(2 H)-yl)-3-Cyclohexylpropanoic Acid 6b

[0067] .sup.1H NMR (300 MHz, DMSO-d6) 6 13.12 (s, 1 H), 7.83-7.77 (m, 2 H), 7.35 (dd, J.sub.1=7.2 Hz, J.sub.2 =1.5 Hz, 1 H), 6.30 (t, J =7.2 Hz, 1 H), 5.35 (dd, J.sub.1=10.8 Hz, J.sub.2 =4.5 Hz, 1 H), 2.10-1.92 (m, 2 H), 1.78-1.69 (m, 1 H), 1.65-1.52 (m, 4 H), 1.47 (s, 9H), 1.13-0.82 (m, 6 H). ESI-MS (m/z): 365 [M +H].sup.+.

Synthesis of Compound 8

[0068] HOBT (245 mg, 1.82 mmol) and EDCI (349 mg, 1.82 mmol) are added to a solution of compound 6 (1.65 mmol) in DCM (20 ml). The mixture is stirred for 1 hat 0° C. Compound 7 methyl (S)-2-amino-3-((S)-2-oxopyrrolidin-3-yl)propanoate (307 mg, 1.65 mmol) is then added, and pH =9 is adjusted with Et3N. The mixture is stirred for 24 h at 0° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH =20/1) (yield of compound 8: 59-67%, light yellow solid).

Methyl (S)-2-((S)-2-(3-((Tert-Butoxycarbonyl)Amino)-2-Oxopyridin-1(2 H)-Yl)-3-Cyclopropylpropanamido)-3-((S)-2-Oxopyrrolidin-3-yl)Propanoate 8a

[0069] .sup.1 H NMR (300 MHz, DMSO-d6) 6 9.00-8.92 (m, 1 H), 7.81-7.77 (m, 2 H), 7.37-7.34 (m, 1 H), 6.30 (t, J=7.2 Hz, 1 H), 5.77 (dd, J.sub.1=10.8 Hz, J.sub.2=4.5 Hz, 1 H), 4.54-4.45 (m, 1 H), 3.74 (s, 3 H), 3.37-3.29 (m, 2 H), 2.35-2.25 (m, 2 H), 1.90-1.71 (m, 5 H), 1.46 (s, 9H), 0.51-0.46 (m, 1 H), 0.32-0.29 (m, 2 H), 0.15-0.11 (m, 1 H), 0.04-0.00 (m, 1 H). ESI-MS (m/z): 491 [M +H].sup.+.

Methyl (S)-2-((S)-2-(3-((Tert-Butoxycarbonyl)amino)-2-Oxopyridin-1(2 H)-yl) Cyclohexylpropanamido)-3-((S)-2-Oxopyrrolidin-3-yl)Propanoate 8b

[0070] ESI-MS (m/z): 533 [M+H].sup.+.

Synthesis of Compound 9

[0071] NaBH.sub.4 (200 mg, 5.3 mmol) is added to a solution of compound 8 (0.53 mmol) in MeOH (6 ml). The mixture is stirred for 3 h at 25° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH=10/1) (yield of compound 9: 49%, approximately white solid).

Tert-Butyl(1-((S)-3-Cyclopropyl-1-(((S)-1-Hydroxy -3-(( )2-Oxopyrrolidin-3-yl)Propan-2-Yl)Amino)-1-Oxopropan-2-Yl)-2-oxo-1,2-Dihydropyridin-3-Yl)Carbamate 9a

[0072] ESI-MS (m/z): 463 [M +H].sup.+.

Tert-butyl(1-((S)-3-Cyclohexyl-1-(((S)-1-Hydroxy-3-((S)-2-Oxopyrrolidin-3-Yl)Propan-2-Yl)Amino)-1-Oxopropan-2-yl)-2-Oxo-1,2-Dihydropyridin-3-Yl)Carbamate 9b

[0073] ESI-MS (m/z): 505 [M +H].sup.+.

Synthesis of Compound 10

[0074] Dess-Martin periodinan (116 mg, 0.27 mmol) and NaHCO.sub.3 (8 mg, 0.09 mmol) are added to a solution of compound 9 (0.26 mmol) in DCM (15 ml). The mixture is stirred for 1 h at 20° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH =20/1) (yield of compound 10: 83-90%, approximately white solid).

Tert-butyl(1-((S)-3-Cyclopropyl-1-Oxo-1-(((S)-1-Oxo -34(S)-2-Oxopyrrolidin-3-Yl)Propan-2-Yl)Amino)Propan-2-Yl)-2-Oxo-1,2-Dihydropyridin-3-Yl)carbamate 10a

[0075] .sup.1 H NMR (300 MHz, DMSO-d6) 6 9.40 (d, J =7.8 Hz, 1 H), 8.97 (dd, JI =14.1 Hz, J.sub.2=7.2 Hz, 1 H), 7.79-7.73 (m, 2 H), 7.35-7.32 (m, 1 H), 6.30 (t, J =7.5 Hz, 1 H), 5.69-5.62 (m, 1 H), 4.48-4.42 (m, 1 H), 3.20-3.10 (m, 2 H), 2.32-2.15 (m, 2 H), 1.88-1.66 (m, 5 H), 1.46 (s, 9H), 0.55-0.47 (s, 1 H), 0.36-0.29 (m, 2 H), 0.14-0.11 (m, 1 H), 0.04-0.00 (m, 1 H). ESI-MS (m/z): 461 [M +H].sup.+. Tert-butyl(1-((S)-3-cyclohexyl-1-oxo-1-(((S)-1-oxo-3-((S)-2-oxopyrrolidin-3-yl)propan-2-yl)amino)propan-2-yl)-2-oxo-1,2- dihydropyridin-3-yl)carbamate 10b:

[0076] ESI-MS (m/z): 503 [M +H].sup.+.

Synthesis of Compound 11 (General Method)

[0077] Acetic acid (26 mg, 0.44 mmol) and isocyanide (0.22 mmol) are added to a solution of compound 10 (0.22 mmol) in DCM (15 ml). The mixture is stirred for 24 h at 20° C. Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH =20/1) (yield of compound 11: 57-65%, approximately white solid).

Synthesis of Compound 12 (General Method)

[0078] To compound 11 (0.13 mmol) in MeOH (15 mL) and H.sub.2O (3 mL) is added LiOH.H2O (11 mg, 0.26 mmol). The mixture is stirred for 20 min at 20° C. A pH=6-7 is adjusted with 1 N HCl. Under vacuum, the solvent is removed and chromatographed over silica gel for purification

[0079] (DCM/MeOH =10/1) (yield of compound 12: 90-95%, approximately white solid).

Synthesis of Compound 13 (General Method)

[0080] Compound 12 (0.115 mmol) is dissolved in DCM (15 ml), Dess-Martin periodinan (58 mg, 0.14 mmol) and NaHCO.sub.3 (4 mg, 0.05 mmol) are added. The mixture is stirred for 1 h at 25° C.

[0081] Under vacuum, the solvent is removed and chromatographed over silica gel for purification (DCM/MeOH =10/1) (yield of compound 13: 69-80%, approximately white solid).

Tert-butyl(1-((S)- 1-(((S)-4-(Benzylamino)- 3 ,4-Dioxo-1-((S)-2-oxopyrrolidin-3-yl)butan-2-Yl)Amino)-3-Cyclopropyl-1-Oxopropan-2-Yl)-2-Oxo-1, 2-dihydropyridin-3-yl)carbamate 13a

[0082] .sup.1 H NMR (300 MHz, DMSO-d.sub.6) δ9.25 (d, J=5.4 Hz, 1 H), 9.00 (dd, J.sub.1=14.1 Hz, J.sub.2=7.2 Hz, 1 H), 7.79-7.69 (m, 3 H), 7.35-7.22 (m, 5 H), 6.30-6.24 (m, 1 H), 5.69-5.61 (m, 1 H), 4.97 (s, br, 1 H), 4.29 (s, 2 H), 3.17-3.09 (m, 2 H), 2.30-2.15 (m, 2 H), 1.91-1.62 (m, 5 H), 1.46 (s, 9H), 0.52-0.47 (m, 1 H), 0.33-0.29 (m, 2 H), 0.14-0.11 (m, 1 H), 0.05-0.02 (m, 1 H). ESI-MS (m/z): 594 [M +H].sup.+.

Tert-butyl(1-((S)-3-Cyclohexyl- 1-((( )4-(Cyclopropylamino)-3 ,4-Dioxo -1-((S)-2-Oxopyrrolidin-3-Yl)Butan-2-yl)Amino)-1-Oxopropan-2-Yl)-2-Oxo-1,2-Dihydropyridin-3-Yl)Carbamate 13b

[0083] .sup.1 H NMR (300 MHz, CDCl.sub.3) δ8.78-8.50 (m, 1 H), 8.01-7.92 (m, 1 H), 7.65 (d, J=7.5 Hz, 1 H), 7.10-6.90 (m, 2 H), 6.35-6.14 (m, 2 H), 5.85-5.75 (m, 1 H), 5.25-5.10 (m, 1 H), 3.24-3.13 (m, 2 H), 2.75-2.71 (m, 1 H), 2.49-2.20 (m, 1 H), 2.10-1.81 (m, 3 H) 1.80-1.52 (m, 8 H), 1.49 (s, 9H), 1.25-1.01 (m, 4 H), 1.00-0.73 (m, 4 H), 0.56-0.51 (m, 2 H). ESI-MS (m/z): 586 [M +H].sup.+.

Tert-butyl(1-((S)- 1-(((S)-4-(benzylamino)-3 ,4-dioxo -1-((S)-2-Oxopyrrolidin-3-Yl)Butan Yl)amino)-3-Cyclohexyl-l-Oxopropan-2-Yl)-2-Oxo-1,2-Dihydropyridin-3-Yl)Carbamate 13c

[0084] .sup.1 H NMR (300 MHz, CDCl.sub.3) 6 8.74-8.25 (m, 1 H), 7.99-7.91 (m, 1 H), 7.65 (d, J =7.5 Hz, 1 H), 7.33-7.00 (m, 6 H), 6.26 (t, J =7.5 Hz, 1 H), 6.07 (s, 1 H), 5.84-5.73 (m, 1 H), 5.27-5.19 (m, 1 H), 4.48-4.42 (m, 2 H), 3.40-3.30 (m, 2 H), 2.52-2.29 (m, 2 H), 2.10-1.92 (m, 3 H) 1.79-1.53 (m, 7H), 1.50 (s, 9H), 1.24-1.01 (m, 4 H), 1.00-0.76 (m, 2 H), ESI-MS (m/z): 636 [M +H].sup.+.

Synthesis of compound 14 (General Method)

[0085] To compound 13 (0.11 mmol) is added a solution of 4N HC1/EA (30 ml). The mixture is stirred for 1 h at 25° C.Then, under reduced pressure, the solvent is removed and diethyl ether (2 ml) is added to the residue with stirring. The white solid is precipitated, filtered, and the filter cake is washed with diethyl ether (1 mL). (Yield of compound 14: 58-94%, white solid).

(S)-3-((S)-2-(3-Amino-2-oxopyridin-1(2 H)-Yl)-3-Cyclopropylpropanamido)-N-benzyl-2-Oxo-4-((S)-2-Oxopyrrolidin-3-Yl)Butanamide 14a

[0086] .sup.1 H NMR (300 MHz, DMSO-d6) 6 9.25 (d, J =5.4 Hz, 1 H), 9.06 (dd, J.sub.1=14.1 Hz, J.sub.2=7.2 Hz, 1 H), 7.73-7.59 (m, 2 H), 7.34-7.21 (m, 5 H), 6.30 (t, J =7.5 Hz, 1 H), 5.75-5.64 (m, 1 H), 5.00 (s, br, 1 H), 4.30 (s, 2 H), 3.17-3.09 (m, 2 H), 2.26-2.12 (m, 2 H), 1.99-1.63 (m, 5 H), 1.46 (s, 9H), 0.49-0.46 (m, 1 H), 0.32-0.30 (m, 2 H), 0.15-0.14 (m, 1 H), 0.05-0.00 (m, 1 H). ESI-MS (m/z): 494 [M +H]t

(S)-3-((S)-2-(3-Amino-2-Oxopyridin-1(2 H)-Yl)-3-Cyclohexylpropanamido)-N-Cyclopropyl-2-Oxo-4-((S)-2-Oxopyrrolidin-3-Yl)Butanamide 14b

[0087] .sup.1 H NMR (300 MHz, DMSO-d6) 6 9.18-9.05 (m, 1 H), 8.78-8.71 (m, 1 H), 7.72 (d, J =7.5 Hz, 1 H), 7.59-7.57 (m, 1 H), 7.40-7.38 (m, 1 H), 6.30 (t, J =7.5 Hz, 1 H), 5.78-5.74 (m, 1 H), 4.96 (s, br, 1 H), 3.28-3.18 (m, 2 H), 2.74-2.71 (m, 1 H), 2.36-2.25 (m, 1 H), 2.10-2.00 (m, 1 H), 1.98-1.77 (m, 3 H) 1.73-1.52 (m, 7 H), 1.10-0.73 (m, 6 H), 0.64-0.55 (m, 4 H). ESI-MS (m/z): 486 [M +H].sup.+.

(S)-3-((S)-2-(3-Amino-2-Oxopyridin-1(2 H)-yl)-3-Cyclohexylpropanamido)-N-Benzyl-2-Xxo-4-((S)-2-Oxopyrrolidin-3-yl)Butanamide 14c

[0088] .sup.1H NMR (300 MHz, DMSO-d.sub.6) δ9.29-9.06 (m, 2 H), 7.99-7.91 (m, 1 H), 7.73 (d, J=7.5 Hz, 1 H), 7.52-7.50 (m, 1 H), 7.34-7.23 (m, 6 H), 6.28 (t, J=7.5 Hz, 1 H), 5.81-5.71 (m, 1 H), 5.10-4.98 (m, 1 H), 4.31-4.29 (m, 2 H), 3.29-3.19 (m, 2 H), 2.35-2.17 (m, 2 H), 1.89-1.78 (m, 3 H) 1.67-1.58 (m, 7 H), 1.20-0.79 (m, 6H). ESI-MS (m/z): 536 [M+H].sup.+.