MK 5172, GRAZOPREVIR

GRAZOPREVIR

• Grazoprevir hydrate
• UNII-4O2AB118LA
• MK 5172

THERAPEUTIC CLAIM Antiviral

Note……..drug is k salt

MF C38H49N6O9SK
MW804.99

CHEMICAL NAMES

1. Cyclopropanecarboxamide, N-[[[(1R,2R)-2-[5-(3-hydroxy-6-methoxy-2-
quinoxalinyl)pentyl]cyclopropyl]oxy]carbonyl]-3-methyl-L-valyl-(4R)-4-hydroxy-L-prolyl-1-
amino-N-(cyclopropylsulfonyl)-2-ethenyl-, cyclic (1→2)-ether, hydrate (1 :1) (1R,2S)-

2. (1aR,5S,8S,10R,22aR)-N-{(1R,2S)-1-[(cyclopropylsulfonyl)carbamoyl]-2-
ethenylcyclopropyl}-5-(1,1-dimethylethyl)-14-methoxy-3,6-dioxo-
1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-
methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-
carboxamide hydrate

MOLECULAR FORMULA C38H50N6O9S.H2O
MOLECULAR WEIGHT 784.92

SPONSOR Merck Sharp & Dohme Corp.

CAS REGISTRY NUMBER 1350462-55-3  HYDRATE, 1350514-68-9 (anhydrous)

WHO NUMBER
9857

GRAZOPREVIR

MERCK

MK-5172 is in phase II clinical development at Merck & Co. for the oral treatment of chronic hepatitis C in combination with peginterferon and ribavirin and in combination with MK-8742. Phase I clinical trials are ongoing for the treatment of hepatitis C in patients with genotype 1 and genotype 3. In 2013, breakthrough therapy designation was assigned to the compound.

 SYNTHESIS, THESIS PROCEDURES, NMR see...........http://www.allfordrugs.com/2015/07/31/mk-5172-grazoprevir/

Discovery of MK-5172, a macrocyclic hepatitis C virus NS3/4a protease inhibitor
ACS Med Chem Lett 2012, 3(4): 332DOI: 10.1021/ml300017p

Development of a practical, asymmetric synthesis of the hepatitis c virus protease inhibitor MK-5172
Org Lett 2013, 15(16): 4174

References on MK-5172 hydrate:
[1]. Steven Harper , John A. McCauley , Michael T. Discovery of MK-5172, a Macrocyclic Hepatitis C Virus NS3/4a Protease Inhibitor. ACS Med. Chem. Lett., 2012, 3 (4), pp 332-336[2]. Summa V, Ludmerer SW, McCauley JA, MK-5172, a selective inhibitor of hepatitis C virus NS3/4a protease with broad activity across genotypes and resistant variants. Antimicrob Agents Chemother. 2012 Aug;56(8):4161-7.

WO2013142159

WO 2013106631

WO 2013101550

WO 2013028470

WO 2013028471

WO2013028465

WO 2010011566

Description:
IC50 Value: 7.4nM and 7nM for genotype1b and 1a respectively, in replicon system [1]
MK-5172 is a novel P2-P4 quinoxaline macrocyclic HCV NS3/4a protease inhibitor currently in clinical development.
in vitro: In biochemical assays, MK-5172 was effective against a panel of major genotypes and variants engineered with common resistant mutations observed in clinical studies with other NS3/4a protease inhibitors. In the replicon assay, MK-5172 demonstrated subnanomolar to low-nanomolar EC50s against genotypes 1a, 1b, and 2a [2].
in vivo: In rats, MK-5172 showed a plasma clearance of 28 ml/min/kg and plasma half-life of 1.4 hr. When dosed p.o. at 5 mg/kg, the plasma exposure of MK-5172 was good with an AUC of 0.7 uM.hr. The liver exposure of the compound was quite good (23 uM at 4 hr), and MK-5172 remained in liver 24 hr after a single p.o. 5 mg/kg dose. At 24 hr, the liver concentration of MK-5172 was 0.2 uM, which was over 25-fold higher than the IC50 in the replicon assay with 50% NHS. When dosed to dogs, MK-5172 showed low clearance of 5 ml/min/kg and a 3 hr half-life after i.v. 2 mg/kg dosing and had good plasma exposure (AUC=0.4 uM.hr) after a p.o. 1 mg/kg dose [1].
Clinical trial: Evaluation of Hepatic Pharmacokinetics for MK-5172 in Participants With Chronic Hepatitis C . Phase1

Hepatitis C virus (HCV) infection is a major health problem that leads to chronic liver disease, such as cirrhosis and hepatocellular carcinoma, in a substantial number of infected individuals. Current treatments for HCV infection include immunotherapy with recombinant interferon-α alone or in combination with the nucleoside analog ribavirin.

Several virally-encoded enzymes are putative targets for therapeutic intervention, including a metalloprotease (NS2-3), a serine protease (NS3), a helicase (NS3), and an RNA-dependent RNA polymerase (NS5B). The NS3 protease is located in the N-terminal domain of the NS3 protein. NS4A provide a cofactor for NS3 activity.

Potential treatments for HCV infection have been discussed in the different references including Balsano, Mini Rev. Med. Chem. 8(4):307-318, 2008, Rönn et al., Current Topics in Medicinal Chemistry 8:533-562, 2008, Sheldon et al., Expert Opin. Investig. Drugs 16(8):1171-1181, 2007, and De Francesco et al., Antiviral Research 58:1-16, 2003

Different HCV inhibitors are described in different publications. Macrocyclic compounds useful as inhibitors the HCV protease inhibitors are described in WO 06/119061, WO 7/015785, WO 7/016441, WO 07/148,135, WO 08/051,475, WO 08/051,477, WO 08/051,514, WO 08/057,209. Additional HCV NS3 protease inhibitors are disclosed in International Patent Application Publications WO 98/22496, WO 98/46630, WO 99/07733, WO 99/07734, WO 99/38888, WO 99/50230, WO 99/64442, WO 00/09543, WO 00/59929, WO 02/48116, WO 02/48172, British Patent No. GB 2 337 262, and U.S. Pat. No. 6,323,180.

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NMR

¹³C NMR (100 MHz, DMSO-d₆) δ 172.32, 170.63, 169.04, 159.86, 156.95, 154.74, 148.10, 140.41, 133.55 (2 signals), 128.94, 118.21, 117.58, 105.89, 74.88, 59.75, 58.71, 55.68, 54.13, 54.01, 40.13, 34.49, 34.04, 33.76, 32.68, 30.71, 30.43, 28.55, 27.69, 27.28, 26.38, 21.98, 18.49, 10.67, 5.69, 5.46; MS (ES⁺) m/z 767 (M+H)⁺

(1aR,5S,8S,10R,22aR)-5-tert-butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxamide

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NMR OF GRAZOPREVIR K SALT

Potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-
1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-
methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-
yl]carbonyl}amino)-2-ethenylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide (15 K-salt).

1H NMR (400 MHz, DMSO-d6) δ 7.91 (br s, 1 H), 7.75 (d, J =
8.3 Hz, 1 H), 7.15 (m, 1 H), 7.04 (m, 1 H), 5.97 (m, 1 H), 5.73 (br s, 1 H), 4.96 (m, 1 H), 4.79 (apparent q, J = 9.3 Hz, 1 H), 4.26 (dd, J = 9.7, 7.7 Hz, 1 H), 4.20 (d, J = 11.3 Hz, 1 H), 4.14 (d, J = 8.8 Hz, 1 H), 3.90 (dd, J = 11.1, 3.2 Hz, 1 H), 3.86 (s, 3 H), 3.62 (m, 1 H), 2.86-2.60 (m, 3 H), 2.38 (m, 1 H), 2.21 (m, 1 H), 1.80-1.48 (m, 6 H), 1.42 (m, 5 H), 1.14 (m, 1 H), 0.95 (m, 10 H), 0.81 (m, 2 H), 0.72-0.50 (m, 3 H), 0.41 (m, 1 H) ppm.http://pubs.acs.org/doi/suppl/10.1021/ml300017p/suppl_file/ml300017p_si_001.pdf

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GRAZOPREVIR

(1aR,5S,8S,10R,22aR)-5-tert-Butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino] carbonyl}-2-
vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-
7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-
carboxamide (MK-5172, 15).

1H NMR (400 MHz, CD3
OD) δ 7.79 (dd, J = 9.6, 1.8 Hz, 1 H), 7.23 (s, 1 H), 7.22 (m, 1 H), 7.10 (d, J = 9.6 Hz, 1 H), 6.01 (apparent t, J = 3.6 Hz, 1 H), 5.74 (m, 1 H), 5.24 (dd, J = 17.0 Hz, 1.6 Hz, 1 H), 5.11 (dd, J = 10.4 Hz, 1.6 Hz, 1 H), 4.49 (d, J = 11.2 Hz, 1 H), 4.40 (m, 2 H), 4.13 (dd, J = 12.0 Hz, 4.0 Hz, 1 H), 3.92 (s, 3 H), 3.76 (m, 1 H), 2.92 (m, 2 H), 2.85 (m, 1 H), 2.55 (dd, J = 13.6 Hz, 6.4 Hz, 1 H), 2.28 (m, 1 H), 2.18 (apparent q, J =8.8 Hz, 1 H), 1.85 (dd, J = 8.0 Hz, 5.6 Hz, 1 H), 1.73 (m, 2 H), 1.5 (m, 2 H), 1.40 (dd, J = 9.6 Hz, 5.6 Hz, 1 H), 1.3 (m, 2 H), 1.23 (m, 4 H), 1.08 (s, 9 H), 0.99 (m, 2 H), 0.89 (m, 3 H), 0.73 (m, 1 H), 0.49 (m, 1 H) ppm; HRMS (ESI) m/z 767.3411 [(M+H)+; calcd for C38H51N6O9S: 767.3433].http://pubs.acs.org/doi/suppl/10.1021/ml300017p/suppl_file/ml300017p_si_001.pdf

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HPLC

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http://www.google.nl/patents/US8080654

SYNTHESIS OF INTERMEDIATES Intermediates A

Intermediate #	Structure	Name	Lit. Reference
A1		(1R,2S)-1-Amino-N- (cyclopropylsulfonyl)-2- vinylcyclopropanecarboxamide hydrochloride	Wang et al., U.S. Pat. No. 6,995,174

Intermediate B1 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine

Step 1: [(1E)-hepta-1,6-dien-1-yloxy](trimethyl)silane

A solution (0.5 M) of butenyl magnesium bromide in THF (1.4 eq) was treated at −78° C. with Cu(I) Br.SMe₂ (0.05 eq) and HMPA (2.4 eq). The mixture was stirred for 10 min, then a solution (1 M) of acrolein (1 eq) and TMSCl (2 eq) in THF was added over 1 h such that the internal temperature remained below −68° C. The resulting mixture was stirred at −78° C. for 2 h, then treated with excess Et₃N and diluted with hexane. After reaching room temperature, the mixture was treated with a small portion of H₂O and filtered through CELITE. The filtrate was washed 10 times with H₂O and then with brine. The organic layer was dried, and the volatiles were removed to give a residue that was distilled under reduced pressure (20 mbar). The fraction collected at 80-86° C. contained the title compound (58%) as a colorless liquid. ¹H NMR (400 MHz, CDCl₃) δ 6.19 (d, J=11.6 Hz, 1H), 5.85-5.75 (m, 1H), 5.02-4.92 (m, 3H), 2.08-2.02 (m, 2H), 1.94-1.88 (m, 2H), 1.46-1.38 (m, 2H), 0.18 (s, 9H).

Step 2: trans-2-pent-4-en-1-ylcyclopropanol

A solution (0.45 M) of the preceding compound in hexane was treated with a solution (15%) of Et₂Zn (1.2 eq) in toluene, and the resulting solution was cooled in an ice bath. Diiodomethane (1.2 eq) was added dropwise, then the solution was stirred for 1 h before being warmed to 20° C. Pyridine (6 eq) was added, and the slurry was stirred for 15 min then poured onto petroleum ether. The mixture was filtered repeatedly through CELITE until a transparent solution was obtained. This mixture was concentrated at 100 mbar, and the solution that remained (that contained trimethyl{[(trans)-2-pent-4-en-1-ylcyclopropyl]oxy}silane, toluene and pyridine) was further diluted with THF. The mixture was cooled to 0° C. then treated dropwise with a solution (1 M) of TBAF (1.2 eq) in THF. After 10 min, the mixture was allowed to warm to 20° C., and after a further 1 h was poured into H₂O. The aqueous phase was extracted with EtOAc, and the combined organic extracts were washed with brine then dried. Removal of the volatiles afforded a residue that was purified by flash chromatography (eluent 0-66% Et₂O/petroleum ether) to furnish the title compound (71%) as a colorless liquid. ¹H NMR (400 MHz, CDCl₃) δ 5.85-5.75 (m, 1H), 5.00 (dd, J=17.1, 1.6 Hz, 1H), 4.94 (br d, J=10.4 Hz, 1H), 3.20 (apparent dt, J=6.4, 2.5 Hz, 1H), 2.10-2.04 (m, 2H), 1.52-1.44 (m, 2H), 1.29-1.19 (m, 1H), 1.15-1.07 (m, 1H), 0.95-0.87 (m, 1H), 0.71-0.66 (m, 1H), 0.31 (apparent q, J=6.0 Hz, 1H).

Step 3: methyl 3-methyl-N-(oxomethylene)-L-valinate

A solution (0.39 M) of methyl 3-methyl-L-valinate in a 2:1 mixture of saturated aqueous NaHCO₃ and CH₂Cl₂ was cooled in an ice bath and stirred rapidly. The mixture was treated with triphosgene (0.45 eq) in one portion, and the resulting mixture was stirred for 0.5 h. The reaction was diluted with CH₂Cl₂, and the layers were separated. The aqueous phase was extracted with CH₂Cl₂, then the combined organics were washed with brine and dried. Removal of the solvent gave the title compound as clear oil that was kept for 12 h under vacuum (0.1 mbar) then used directly in the subsequent step. ¹H NMR (400 MHz, CDCl₃) δ 3.79 (s, 3H), 3.75 (s, 1H), 1.00 (s, 9H).

Step 4: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate and methyl 3-methyl-N-({[(1S,2S)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate

A solution (0.45 M) of trans-2-pent-4-en-1-ylcyclopropanol in toluene was treated with methyl 3-methyl-N-(oxomethylene)-L-valinate (1.1 eq) and then DMAP (1 eq). The resulting mixture was heated under reflux for 12 h then cooled to 20° C. H₂O and EtOAc were added, and the organic layer was separated and washed with 1N HCl, brine and dried. Removal of the volatiles afforded a residue that was purified twice by flash chromatography (eluent 0-30% Et₂O/petroleum ether). The first fractions contained methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate (38%) as an oil. MS (ES⁺) m/z 298 (M+H)⁺

The later fractions contained methyl 3-methyl-N-({[(1S,2S)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate (28%) as an oil. MS (ES⁺) m/z 298 (M+H)⁺

Step 5: 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine

A solution (0.1 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate in 2:1 mixture of MeOH/H₂O was treated with LiOH.H₂O (4 eq) and then heated at 60° C. for 4 h. The mixture was cooled and concentrated to half volume, then diluted with EtOAc and acidified with aqueous HCl (1 N). The organic layer was separated and washed with brine then dried. Removal of the volatiles afforded the title compound (98%) as an oil. MS (ES⁺) m/z 284 (M+H)⁺

Intermediates C Intermediate C1 methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride

Step 1: 6-methoxyquinoxaline-2,3-diol

A suspension of 4-methoxybenzene-1,2-diamine dihydrochloride in diethyl oxalate (8 eq) was treated with Et₃N (2 eq) and then heated at 150° C. for 2 h. The mixture was cooled and filtered, and then the collected solid was washed with H₂O and EtOH. The residue was dried to give the title compound (69%). MS (ES⁺) m/z 193 (M+H)⁺

Step 2: 3-chloro-6-methoxyquinoxalin-2-ol

A solution (1.53 M) of 6-methoxyquinoxaline-2,3-diol in DMF was treated with SOCl₂ (1 eq) and heated at 110° C. After 1.5 h, the reaction mixture was cooled and poured into aqueous HCl (1 N). The resulting precipitate was filtered and washed with H₂O and Et₂O. The dried solid contained predominantly the title compound as a mixture with 6-methoxyquinoxaline-2,3-diol and 2,3-dichloro-6-methoxyquinoxaline. This material was used directly in the subsequent step. MS (ES⁺) m/z 211 (M+H)⁺

Step 3: 1-tert-butyl 2-methyl (2S,4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]pyrrolidine-1,2-dicarboxylate

A solution (0.35 M) of 3-chloro-6-methoxyquinoxalin-2-ol in NMP was treated with Cs₂CO₃ (1.5 eq) and 1-tert-butyl 2-methyl (2S,4S)-4-{[(4-bromophenyl)sulfonyl]oxy}pyrrolidine-1,2-dicarboxylate (1.1 eq). The resulting mixture was stirred at 50° C. for 18 h, then a further portion (0.1 eq) of 1-tert-butyl 2-methyl (25,45)-4-{[(4-bromophenyl)sulfonyl]oxy}pyrrolidine-1,2-dicarboxylate was added. After stirring for 2 h, the mixture was cooled and diluted with H₂O and EtOAc. The organic phases were washed with aqueous HCl (1 N), saturated aqueous NaHCO₃ and brine. The dried organic phase was concentrated to a residue that was purified by flash-chromatography (0-60% EtOAc/petroleum ether) to give the title compound (35% for two steps) as a solid. MS (ES⁺) m/z 438 (M+H)⁺

Step 4: methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride

A solution (0.62 M) of 1-tert-butyl 2-methyl (2S,4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]pyrrolidine-1,2-dicarboxylate in CH₂Cl₂ was treated with a solution (4 M) of HCl in dioxane (5 eq). The mixture was stirred at 20° C. for 2 h, then treated with a solution (4 M) of HCl in dioxane (2 eq). After 5 h, the reaction was judged complete and the mixture was concentrated under reduced pressure. The residue was triturated with Et₂O to give the title compound (95%) as a solid. MS (ES⁺) m/z 338 (M+H)⁺

Example 1 Potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-yl]carbonyl}amino)-2-vinylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide

Step 1: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate

A solution (0.2 M) of methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride in DMF was treated with 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine (1.1 eq), DIEA (5 eq) and HATU (1.2 eq). The resulting mixture was stirred at 20° C. for 5 h, then diluted with EtOAc. The organic layer was separated and washed with aqueous HCl (1 N), saturated aqueous NaHCO₃ and brine. The dried organic phase was concentrated under reduced pressure to give a residue that was purified by flash chromatography (eluent 10-30% EtOAc/petroleum ether) to furnish the title compound (96%) as an oil. MS (ES⁺) m/z 604 (M+H)⁺

Step 2: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(7-methoxy-3-vinylquinoxalin-2-yl)oxy]-L-prolinate

A solution (0.1 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate in EtOH was treated with potassium trifluoro(vinyl)borate (1.5 eq) and triethylamine (1.5 eq). The resulting mixture was degassed, then PdCl₂(dppf)-CH₂Cl₂ adduct (0.1 eq) was added. The mixture was heated under reflux for 1 h, then cooled to room temperature and diluted with H₂O and EtOAc. The organic phase was separated, washed with H₂O and brine then dried. Removal of the volatiles afforded a residue that was purified by flash chromatography (20-30% EtOAc/petroleum ether) to give the title compound as a yellow foam that was used directly in the subsequent step. MS (ES⁺) m/z 595 (M+H)⁺

Step 3: methyl (1aR,5S,8S,10R,18E,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,20,21,22,22a-dodecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate

A solution (0.02 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(7-methoxy-3-vinylquinoxalin-2-yl)oxy]-L-prolinate in DCE was heated to 80° C. then treated with Zhan 1 catalyst (0.15 eq). The resulting mixture was stirred at 80° C. for 1 h, then cooled to room temperature and concentrated under reduced pressure. The residue was purified by flash chromatography (20-50% EtOAc/petroleum ether) to give the title compound (25% for 2 steps) as a foam. MS (ES⁺) m/z 567 (M+H)⁺

Step 4: methyl (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate

A solution (0.05 M) of methyl (1aR,5S,8S,10R,18E,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,20,21,22,22a-dodecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate in MeOH/dioxane (1:1 ratio) was treated with Pd/C (8% in weight). The resulting mixture was stirred under atmosphere of hydrogen for 4 h. The catalyst was filtered off, and the filtrate was concentrated under reduced pressure to give the title compound (98%) as a solid. MS (ES⁺) m/z 569 (M+H)⁺

Step 5: (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylic acid

A solution (0.1 M) of methyl (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate in a 1:1 mixture of H₂O/THF was treated with LiOH.H₂O (3 eq). The resulting mixture was stirred at 20° C. for 18 h, acidified with aqueous HCl (0.2 M) and diluted with EtOAc. The organic phase was separated, washed with aqueous HCl (0.2 M) and brine then dried. Removal of the volatiles afforded the title compound (98%) as a solid. MS (ES⁺) m/z 555 (M+H)⁺

Step 6: (1aR,5S,8S,10R,22aR)-5-tert-butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxamide

A solution (0.1 M) of (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylic acid in CH₂Cl₂ was treated with (1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropanaminium chloride (1.3 eq), DIEA (3 eq), DMAP (1.5 eq) and TBTU (1.45 eq). The resulting mixture was stirred at 20° C. for 18 h and then diluted with EtOAc. The solution was washed with aqueous HCl (0.2 M), saturated aqueous NaHCO₃ and brine. The organic phases were dried and concentrated to give a residue that was purified by flash-chromatography (eluent 2.5% MeOH/CH₂Cl₂) to give the title compound (89%) as a solid. ¹³C NMR (100 MHz, DMSO-d₆) δ 172.32, 170.63, 169.04, 159.86, 156.95, 154.74, 148.10, 140.41, 133.55 (2 signals), 128.94, 118.21, 117.58, 105.89, 74.88, 59.75, 58.71, 55.68, 54.13, 54.01, 40.13, 34.49, 34.04, 33.76, 32.68, 30.71, 30.43, 28.55, 27.69, 27.28, 26.38, 21.98, 18.49, 10.67, 5.69, 5.46; MS (ES⁺) m/z 767 (M+H)⁺

GRAZOPREVIR POTASSIUM

Step 7: potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-yl]carbonyl}amino)-2-vinylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide

The preceding material was taken up in EtOH and the resulting solution (0.025 M) was cooled to 0° C. A solution (0.02 M) of tert-BuOK (1.5 eq) in EtOH was added leading to the formation of a precipitate. The mixture was stirred at 20° C. for 18 h, then the solid was collected by filtration. This material was washed with EtOH and dried to give the title compound (93%) as a white crystalline solid. MS (ES⁺) m/z 767 (M+H)^{+http://www.google.nl/patents/US8080654}

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PATENT

WO 2015095437

https://patentscope.wipo.int/search/en/detail.jsf;jsessionid=7B0847E0F0E112A849B1647ECFBB663D.wapp1nB?docId=WO2015095437&recNum=31&maxRec=12184&office=&prevFilter=&sortOption=&queryString=EN_ALL%3Anmr+AND+PA%3Amerck&tab=PCTDescription

Step 1: Quinoxaline Hydroxyproline Methyl Ester HCl Salt

A 250-ml RB, equipped with magnetic stirrer and N₂ bubbler, was charged with chloroquinoxaline BOC hydroxyproline adduct in MeOH (100 ml), and the mixture was cooled in an ice bath. Acetyl chloride (17.9 g) was then added, and the mixture was stirred at RT for 2 h. The batch was diluted with IP Ac (80 ml). Solids were filtered off and washed with IPAc (20 ml). The washed solids were dried under vacuum for 3 d, to provide 48.9 g (100% yield ). Part of this material was used in the next step.

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WO2015057611

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015057611&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

Example 17: Preparation of Compound A, Method A

Macrocyclic acid hemihydrate, the product of Example 15 (10.16 g, 18.03 mmol) was dissolved in THF (50 mL to 90 mL). The solution was azetropically dried at a final volume of 100 mL. Sulfonamide pTSA salt (7.98 g, 1.983 mmol) followed by DMAc (15 mL) was added at RT. The batch was cooled to 0°C to 10°C, and pyridine (10 mL) was added dropwise. Then, EDC HCl (4.49 g, 23.44 mmol) was added in portions or one portion at 0°C to 10°C. The reaction mixture was aged at 0°C to 10°C for 1 h, and then warmed to 15°C to 20°C for 2 h to 4 h. MeOAc (100 mL) followed by 15 wt% citric acid in 5% NaCl in water (50 mL) was added, while the internal temperature was maintained to < 25°C with external cooling. The separated organic phase was washed with 15 wt% citric acid in 5% NaCl in water (50 mL) followed by 5% NaCl (50 mL). The organic phase was solvent-switched to acetone at a final volume of ~80 mL. Water (10 mL) was added dropwise at 35°C to 40°C. The batch was seeded with Compound A monohydrate form III (~10 mg) and aged for 0.5 h tol h at 35°C to 40°C. Additional water (22 mL) was added dropwise over 2 h to 4 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 60% acetone in water (2x 40 mL). Suction drying at RT gave Compound A monohydrate form III as a white solid.
^XH NMR (400 MHz, CDC1₃) δ 9.95 (s, br, 1 H), 7.81 (d, J = 9.1 Hz, 1 H), 7.18 (dd, J = 9.1, 2.7 Hz, 1 H), 7.16 (s, br, 1 H), 7.13 (d, J = 2.7 Hz, 1 H), 5.96 (t, J = 3.8 Hz, 1 H), 5.72 (m, 1 H), 5.68 (d, J = 10.1 Hz, 1 H), 5.19 (d, J = 17.1 Hz, 1 H), 5.07 (d, J = 10.1 Hz, 1 H), 4.52 (d, J = 11.4 Hz, 1 H), 4.45 (d, J = 9.8 Hz, 1 H), 4.36 (d, J = 10.5, 6.9 Hz, 1 H), 4.05 (dd, J = 11.5, 3.9 Hz, 1 H), 3.93 (s, 3 H), 3.78 (m, 1 H), 2.90 (m, 1 H), 2.82 (tt, J = 8.0, 4.8 Hz, 1 H), 2.74 (dt, J = 13.2, 4.8 Hz, 1 H), 2.59 (dd, J = 14.0, 6.7 Hz, 1 H), 2.40 (ddd, J = 14.0, 10.6, 4.0 Hz, 1 H), 2.10 (dd, J = 17.7, 8.7 Hz, 1 H), 1.98 (2 H, mono hydrate H₂0), 1.88 (dd, J 8.2, 5.9 Hz, 1 HO, 1.74 (m, 3 H), 1.61 (m, 1 H), 1.50 (m, 3 H), 1.42 (dd, J = 9.6, 5.8 Hz, 1 H), 1.22 (m, 2 H), 1.07 (s, 9 H), 0.95 (m, 4 H), 0.69 (m, 1 H), 0.47 (m, 1 H).
¹ C NMR (100 MHz, CDC1₃) δ 173.5, 172.1, 169.1, 160.4, 157.7, 154.9, 148.4, 141.0, 134.3, 132.7, 129.1, 118.8, 118.7, 106.5, 74.4, 59.6, 59.4, 55.8, 55.5, 54.9, 41.8, 35.4, 35.3, 35.2, 34.3,. 31.2, 30.7, 29.5, 28.6, 28.2, 26.6, 22.6, 18.7, 11.2, 6.31, 6.17.
HPLC conditions: Ascentis Express Column, 10 cm x 4.6 mm, 2.7 μηι; Column temperature of 40°C; Flow rate of 1.8 mL/min; and Wavelength of 215 nm.
Gradiant: mm 0.1% ¾PO4
0 20 80
5 55 45
15 55 45
25 95 5
27 95 5
27.1 20 80
32 20 80
Retention time: mm.
Compound A 14.50
Example 18: Preparation of Compound A, Method B

To a 50-L flask equipped with overhead stirring was added macrocyclic acid (1.06 kg crude, 1.00 eq), amine-pTSA (862 g crude, 1.12 eq) and MeCN (7.42 L) at 19°C. The slurry was cooled in a water bath, pyridine (2.12 L, 13.8 eq) was added, aged 15 min, and then added EDC (586 g, 1.60 eq) in one portion, aged 1.5 h, while it turned into a clear homogeneous solution.
The solution cooled in a water bath, then quenched with 2 N HC1 (1.7 L), and seeded (9.2 g), aged 15 min, and the rest of the aqueous HC1 was added over 2.5 h. A yellow slurry was formed. The slurry was aged overnight at RT, filtered, washed with MeCN/water (1 : 1 v/v, 8 L), to obtain Compound A (Hydrate II).
Compound A was dissolved in acetone (4 L) at RT, filtered and transferred to a
12-L round-bottom flask with overhead stirring, rinsed with extra acetone (1 L), heated to 50°C, water (0.9 L) was added, seeded with Compound A monohydrate form III (-10 mg), and aged 15 min, and then added water (0.8 L) over 2.5 h, extra water 3.3 v over 2.5 h was added, stopped heating, cooled to RT, aged at RT overnight, filtered, washed with water/acetone (1 : 1 v/v, 4 L), and dried in air under vacuum. Compound A Hydrate III, 670 g, was obtained as an off-white solid.
Example 19: Preparation of Compound A, Method C

Macrocyclic acid hemihydrate from Example 15 (10.16 g, 18.03 mmol) was dissolved in THF (50 ml to 90 mL). The solution was azetropically dried at a final volume of 100 mL. Sulfonamide pTSA salt (7.98 g, 19.83 mmol) was added, followed by DMAc (15 mL), at RT. The batch was cooled to 0° to 10°C, and pyridine (10 mL) was added dropwise. Then, EDC HC1 (4.49 g, 23.44 mmol) was added (in portions or one portion) at 0°C to 10°C. The reaction mixture was aged at 0°C to 10°C for 1 h, and then warmed to 15°C to 20°C for 2 h to 4 h. THF (50 mL) was added, followed by 15 wt% citric acid in 15 wt% aq. NaCl (50 mL), while the internal temperature was maintained at < 25°C with external cooling. The separated organic phase was washed with 15 wt% citric acid in 1 % aq. NaCl (40 mL), followed by 15% NaCl (40 mL). The organic phase was solvent-switched to acetone at a final volume of ~75 mL Water (1 1 mL to 12 mL) was added dropwise at 35°C to 40°C. The batch was seeded with Compound A monohydrate form III (~20 mg) and aged for 0.5 h to 1 h at 35°C to 40°C.
Additional water (22 mL) was added dropwise over 2 h to 4 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 60% acetone in water (40 mL x 2). Suction drying at RT or vacuum-oven drying at 45°C gave Compound A monohydrate form III as a white solid.
Example 20: Preparation of Compound A, Method D

Macrocyclic acid hemihydrate from Example 12 (10 g, 98.4wt%, 17.74 mmol) was dissolved in THF (70 mL). The solution was azetropically dried at a final volume of ~60 mL. Sulfonamide pTSA salt (7.53 g, 18.7 mmol) was added at RT. The batch was cooled to 0°C to 5°C, and pyridine (1 1.4 mL) was added dropwise. Then, EDC HC1 (4.26 g, 22.2 mmol) was added in portions at 0°C to 15°C. The reaction mixture was aged at 10°C to 15°C for 2 h to 4 h. 35 wt% Citric acid in 10 wt% aq. NaCl (80 mL) was added, while the internal temperature was maintained at < 25°C with external cooling. The separated organic phase was solvent-switched to acetone at a final volume of ~75 mL. Water (12 mL) was added dropwise at 50°C. The batch was seeded with Compound A monohydrate form III (-300 mg) and aged for 0.5 h to 1 h at 50°C. Additional water (25 mL) was added dropwise over 6 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 65%) acetone in water (40 mL). Suction drying at RT or vacuum-oven drying at 45°C gave Compound A monohydrate form III as a white solid.

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WO2015095430

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015095430&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

Example 24: Ring Closing Metathesis

To a 50 mL 2-neck RB flask with reflux condenser and needle for N₂ bubbling was charged the product of Example 20 (1.034 g, 0.869 mmol, 1.0 eq), toluene (20.68 ml, 20X), and the resulting solution was degassed with N₂. Hoveyda-Grubbs 2^nd generation catalyst (10.90 mg, 0.017 mmol) was charged to the pot, and the system was heated to 80°C with constant sparge of N₂, with color change from green to reddish. The reaction was sampled (5 h) and assay by HPLC to be approximately 80% converted. The system was removed from the heat and allowed to stir at RT overnight under N₂. The reaction was again assayed and deemed complete by HPLC. Toluene was removed by concentration and the resulting red oil was purified by gradient silica gel chromatography (50 g BlOTAGE SNAP Si gel column; loaded with DCM; eluted with 0 to 10% EtOAc in DCM over 10 column volumes; then 10 to 20% EtOAc in DCM over 3 column volumes; then hold; detect by TLC-UV) to yield a yellow solid, which was further slurried in EtOAc (3 mL) and hexanes (6 mL). The resulting slurry was filtered and washed with 25% EtOAc in hexanes (6 mL) to yield the product (445 mg, 0.754 mmol, 87% yield) as a white solid.

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http://anewmerckreviewed.wordpress.com/2013/04/23/okay-trivial-pursuit-will-the-real-mk-5172-please-stand-up/

Merck reported interim data from the Phase 2 C-WORTHY study in April 2014 at the International Liver Congress (ILC) in London that evaluated the efficacy and safety of its two-drug regimen based on NS3/4A protease inhibitor MK-5172 and NS5A replication complex inhibitor MK-8742, given with or without ribavirin, in GT1 HCV patients with cirrhosis. The once-daily single pill (without ribavirin) showed a 98% SVR12 (12-week sustained virologic response) in genotype-1, treatment-naive patients. Merck will start the phase III clinical trials (NCT02105688, NCT02105662, NCT02105467 andNCT02105701) for the combination in June 2014.

MK-5172 is a novel, competitive inhibitor of the HCV NS3/4a protease with selective, potent in vitro activity against a broad range of HCV genotypes (GTs) and known viral variants that are resistant to other protease inhibitors in development.

MK-5172 is a Next Generation HCV NS3/4a Protease Inhibitor with a Broad HCV Genotypic Activity Spectrum and Potent Activity Against Known Resistance Mutants, in Genotype 1 and 3 HCV-Infected Patients. MK-5172 exhibits excellent selectivity over other serine proteases such as elastase and trypsin (no measurable inhibition), and shows only modest inhibitory potency with chymotrypsin (IC50 = 1.5 µM; 75,000-fold selective). In the genotype 1b replicon assay, MK-5172 potently inhibits viral replication (IC50 = 2 nM) and demonstrates a modest shift in the presence of 50% NHS (EC50 = 9.5 nM). In vitro, MK-5172 inhibits the NS3/4A enzyme from genotypes 1b, 2a, 2b, and 3a with Ki values of <0.02, 0.15, 0.02, and 0.7 nM, respectively. The genotype 2a replicon is also potently inhibited by MK 5172 (EC50 = 5 nM).

Kuethe J, * Zhong Y.-L, * Yasuda N, * Beutner G, Linn K, Kim M, Marcune B, Dreher SD, Humphrey G, Pei T. Merck Research Laboratories, Rahway, USA
Development of a Practical, Asymmetric Synthesis of the Hepatitis C Virus Protease Inhibitor MK-5172.Org. Lett. 2013;
15: 4174-4177

SignificanceNotify Users About this Post

MK-5172 is a hepatitis C virus protease inhibitor. Key steps in the synthesis depicted are (1) the regioselective SNAr reaction of dichloroquinoxaline A with prolinol derivative B and (2) construction of the 18-membered macrocycle ­using a macrolactamization (F → G).

Comment

The medicinal chemistry route to MK-5172 is based on a ring-closing metathesis strategy (S. Harper et al.ACS Med. Chem. Lett. 2012, 3, 332). The best regioselectivity (20:1) and minimization of double substitution in the SNAr reaction of A with B was achieved using 1,8-diaza­bicyclo[5.4.0]undec-7-ene (DBU) as the base in polar solvents such as DMSO, NMP, or DMAc.

  SYNTHESIS, THESIS PROCEDURES, NMR see...........http://www.allfordrugs.com/2015/07/31/mk-5172-grazoprevir/
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