Ombitasvir

Ombitasvir; ABT-267; ABT 267; UNII-2302768XJ8; 1258226-87-7;

C50H67N7O8
Molecular Weight:	894.10908 g/mol

Anti-Viral Compounds [US2010317568]

Dimethyl (2S,2′S)-1,1′-((2S,2′S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-Butylphenyl)pyrrolidine-2,5-diyl)bis(4,1-phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2,1-diyl))bis(3-methyl-1-oxobutane-2,1-diyl)dicarbamate

methyl N-[(2S)-1-[(2S)-2-[[4-[(2S,5S)-1-(4-tert-butylphenyl)-5-[4-[[(2S)-1-[(2S)-2-(methoxycarbonylamino)-3-methylbutanoyl]pyrrolidine-2-carbonyl]amino]phenyl]pyrrolidin-2-yl]phenyl]carbamoyl]pyrrolidin-1-yl]-3-methyl-1-oxobutan-2-yl]carbamate

1258226-87-7 [RN]

ABT-267
2:9 hydrate cas= 1456607-70-7...... is the drug substance

 Abbvie Inc.  innovator

ombitasvir is Dimethyl ([(2S,5S)-1-(4-tert-butylphenyl) pyrrolidine-2,5diyl]bis{benzene-4,1-diylcarbamoyl(2S)pyrrolidine-2,1-diyl[(2S)-3-methyl-1-oxobutane-1,2diyl]})biscarbamate hydrate. The molecular formula is C₅₀H₆₇N7O₈•4.5H₂O (hydrate) and the molecular weight for the drug substance is 975.20 (hydrate).

Ombitasvir is an antiviral drug for the treatment of hepatitis C virus (HCV) infection. In the United States, it is approved by theFood and Drug Administration for use in combination with paritaprevir, ritonavir and dasabuvir in the product Viekira Pak for the treatment of HCV genotype 1,^[1][2] and with paritaprevir and ritonavir in the product Technivie for the treatment of HCV genotype 4.^[3][4]

Ombitasvir is in phase II clinical development at AbbVie for the treatment of chronic hepatitis C infection in combination with ABT-450/ritonavir and, in combination with peginterferon alpha-2a/ribavirin (pegIFN/RBV) in treatment naïve Hepatitis C virus (HCV) genotype 1 infected patients.

Ombitasvir is part of a fixed-dose formulation with ABT-450/ritonavir that is approved in the U.S. and the E.U.
Ombitasvir acts by inhibiting the HCV protein NS5A.^[5]

In 2013, breakthrough therapy designation was assigned in the U.S. for the treatment of genotype 1 hepatitis C in combination with ABT-450, ritonavir and ABT-333, with and without ribavirin.

 

 

 

 DeGoey, DA, Discovery of ABT-267, a Pan-genotypic Inhibitor of HCV NS5A,  J. Med. Chem., 2014, 57 (5), pp 2047-2057

 http://pubs.acs.org/doi/full/10.1021/jm401398x

http://pubs.acs.org/doi/suppl/10.1021/jm401398x/suppl_file/jm401398x_si_001.pdf

We describe here N-phenylpyrrolidine-based inhibitors of HCV NS5A with excellent potency, metabolic stability, and pharmacokinetics. Compounds with 2S,5S stereochemistry at the pyrrolidine ring provided improved genotype 1 (GT1) potency compared to the 2R,5Ranalogues. Furthermore, the attachment of substituents at the 4-position of the central N-phenyl group resulted in compounds with improved potency. Substitution with tert-butyl, as in compound 38 (ABT-267), provided compounds with low-picomolar EC₅₀ values and superior pharmacokinetics. It was discovered that compound 38 was a pan-genotypic HCV inhibitor, with an EC₅₀ range of 1.7–19.3 pM against GT1a, -1b, -2a, -2b, -3a, -4a, and -5a and 366 pM against GT6a. Compound 38 decreased HCV RNA up to 3.10 log₁₀ IU/mL during 3-day monotherapy in treatment-naive HCV GT1-infected subjects and is currently in phase 3 clinical trials in combination with an NS3 protease inhibitor with ritonavir (r) (ABT-450/r) and an NS5B non-nucleoside polymerase inhibitor (ABT-333), with and without ribavirin.

 Dimethyl (2S,2′S)-1,1′-((2S,2′S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-Butylphenyl)pyrrolidine-2,5-diyl)bis(4,1-phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2,1-diyl))bis(3-methyl-1-oxobutane-2,1-diyl)dicarbamate (38)...desired and Dimethyl (2S,2′S)-1,1′-((2S,2′S)-2,2′-(4,4′-((2R,5R)-1-(4-tert-Butylphenyl)pyrrolidine-2,5-diyl)bis(4,1-phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2,1-diyl))bis(3-methyl-1-oxobutane-2,1-diyl)dicarbamate (39).......undesired

................. The resulting mixture was stirred at room temperature for 16 h. The mixture was partitioned between ethyl acetate and water, and the organic layer was washed with saturated aqueous NaHCO₃, brine (2×) and dried with Na₂SO₄. The drying agent was filtered off and the solution was concentrated in vacuo to give a crude product that was purified by column chromatography on silica gel, eluting with a solvent gradient of 2–8% methanol in dichloromethane to give a 1:1 mixture of trans-pyrrolidine isomers (290 mg, 96%). The mixture was separated on a Chiralpak AD-H column, eluting with a mixture of 1 part (2:1 isopropanol/ethanol) and 2 parts hexanes (0.1% TFA).

Compound 38 was the first of two stereoisomers to elute (101 mg, 99% ee by chiral HPLC). ¹H NMR (400 MHz, DMSO-d₆) δ 0.88 (d, J = 6.61 Hz, 6H), 0.93 (d, J = 6.72 Hz, 6H), 1.11 (s, 9H), 1.63 (d, J = 5.42 Hz, 2H), 1.80–2.04 (m, 8H), 2.09–2.19 (m, 2H), 2.44–2.47 (m, 2H), 3.52 (s, 6H), 3.59–3.66 (m, 2H), 3.77–3.84 (m, 2H), 4.02 (t, J = 8.40 Hz, 2H), 4.42 (dd, J = 7.86, 4.83 Hz, 2H), 5.14 (d, J = 6.18 Hz, 2H), 6.17 (d, J = 8.67 Hz, 2H), 6.94 (d, J = 8.78 Hz, 2H), 7.13 (d, J = 8.46 Hz, 4H), 7.31 (d, J= 8.35 Hz, 2H), 7.50 (d, J = 8.35 Hz, 4H), 9.98 (s, 2H).

MS (ESI) m/z 894.9 (M + H)⁺.

Compound39 was the second of two stereoisomers to elute. ¹H NMR (400 MHz, DMSO-d₆) δ 0.87 (d, J = 6.51 Hz, 6H), 0.92 (d, J = 6.72 Hz, 6H), 1.11 (s, 9H), 1.63 (d, J = 5.53 Hz, 2H), 1.82–2.04 (m, 8H), 2.09–2.18 (m, 2H), 2.41–2.47 (m, 2H), 3.52 (s, 6H), 3.58–3.67 (m, 2H), 3.75–3.84 (m, 2H), 4.02 (t, J = 7.26 Hz, 2H), 4.43 (dd, J = 7.92, 4.88 Hz, 2H), 5.14 (d, J = 6.18 Hz, 2H), 6.17 (d, J = 8.78 Hz, 2H), 6.94 (d, J = 8.67 Hz, 2H), 7.12 (d, J = 8.46 Hz, 4H), 7.31 (d, J = 8.35 Hz, 2H), 7.49 (d, J = 8.46 Hz, 4H), 9.98 (s, 2H). MS (ESI) m/z 895.0 (M + H)⁺.

 

...........

WO 2011156578

dimethyl (2S,2^,S)-l,l '-((2S,2'S)-2,2'-(4,4'-((2S,5S)-l-(4-fert-butylphenyl)pyrrolidine- 2,5-diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3- methyl- l-oxobutane-2,l-diyl)dicarbamate

hereinafter Compound IA),..http://www.google.com/patents/WO2011156578A1?cl=en

...................................

US 20100317568

https://www.google.co.in/patents/US20100317568

Example 34

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate and

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-ter/'-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

Example 34A l-(4-fer?-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine The product from Example 1C (3.67 g, 7.51 mmol) and 4-tert-butylaniline (11.86 ml, 75 mmol) in DMF (40 ml) was stirred under nitrogen at 50 °C for 4 h. The resulting mixture was diluted into ethyl acetate, treated with IM HCl, stirred for 10 minutes and filtered to remove solids. The filtrate organic layer was washed twice with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (5% to 30%) to give a solid. The solid was triturated in a minimal volume of 1 :9 ethyl acetate/hexane to give a light yellow solid as a mixture of trans and cis isomers (1.21 g, 36%).

Example 34B 4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline and 4,4'-((2R,5R)-1-(4-fert- butylphenyl)pyrrolidine-2,5-diyl)dianiline To a solution of the product from Example 34A (1.1 g, 2.47 mmol) in ethanol (20 ml) and

THF (20 ml) was added PtC>₂ (0.22 g, 0.97 mmol) in a 50 ml pressure bottle and stirred under 30 psi hydrogen at room temperature for 1 h. The mixture was filtered through a nylon membrane and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (20% to 60%). The title compound eluted as the first of 2 stereoisomers (trans isomer, 0.51 g, 54%).

Example 34C

(2S,2'S)-tert-Butyl 2,2'-(4,4'-((2S,5S)-1-(4-fer/'-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine- 1 -carboxylate and (2S,2'S)-tert-Butyl 2,2'- (4,4'-((2R,5R)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine-1-carboxylate To a mixture of the product from Example 34B (250 mg, 0.648 mmol), (S)-1-(tert- butoxycarbonyl)pyrrolidine-2-carboxylic acid (307 mg, 1.427 mmol) and HATU (542 mg, 1.427 mmol) in DMSO (10 ml) was added Hunig's base (0.453 ml, 2.59 mmol). The reaction mixture was stirred at room temperature for 1 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (10% to 50%) to give the title compound (500 mg, 99%).

Example 34D

(2S,2'S)-N,N'-(4,4'-((2S,5S)-1-(4-ter/'-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))dipyrrolidine-2-carboxamide and (2S,2'S)-N,N'-(4,4'-((2R,5R)-1-(4-tert- butylphenyl)pyrrolidine-2,5-diyl)bis(4,l-phenylene))dipyrrolidine-2-carboxamide To the product from Example 34C (498 mg, 0.638 mmol) in dichloromethane (4 ml) was added TFA (6 ml). The reaction mixture was stirred at room temperature for 1 h and concentrated in vacuo. The residue was partitioned between 3: 1 CHCl₃dsopropyl alcohol and saturated aq. NaHCO₃. The aqueous layer was extracted by 3: 1 CHCl₃:isopropyl alcohol again. The combined organic layers were dried over

filtered and concentrated to give the title compound (345 mg, 93%).

Example 34E Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate and

Dimethyl (2S,2'S)-1, r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34D (29.0 mg, 0.050 mmol), (S)-2-(methoxycarbonylamino)-3- methylbutanoic acid (19.27 mg, 0.110 mmol), EDAC (21.09 mg, 0.110 mmol), HOBT (16.85 mg,

0.110 mmol) and N-methylmorpholine (0.027 ml, 0.250 mmol) were combined in DMF (2 ml). The reaction mixture was stirred at room temperature for 3 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine twice, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (50% to 80%) to give a solid. The solid was triturated with ethyl acetate/hexane to give the title compound (13 mg, 29%). ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.85 - 0.95 (m, 12 H) 1.11 (s, 9 H) 1.59 - 1.65 (m, 2 H) 1.79 - 2.04 (m, 8 H) 2.10 - 2.18 (m, 2 H) 2.41-2.46 (m, 2H) 3.52 (s, 6 H)

3.57 - 3.67 (m, 2 H) 3.76 - 3.86 (m, 2 H) 4.00 (t, J=7.56 Hz, 2 H) 4.39 - 4.46 (m, 2 H) 5.15 (d, J=7.00

Hz, 2 H) 6.17 (d, J=7.70 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=7.37 Hz, 4 H) 7.30 (d, J=8.20

Hz, 2 H) 7.50 (d, J=8.24 Hz, 4 H) 9.98 (s, 2 H); (ESI+) m/z 895 (M+H)+. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 35

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate

..................desired

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the first of the 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 - 2.04 (m, 8 H) 2.09 - 2.19 (m, 2 H) 2.44 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 - 3.66 (m, 2 H) 3.77 - 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV Ib- Conl replicon assays in the presence of 5% FBS.

Example 36 Dimethyl (2S,2'S)-1, r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

.......undesired

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the second of 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.87

(d, J=6.51 Hz, 6 H) 0.92 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.53 Hz, 2 H) 1.82 - 2.04 (m, 8

H) 2.09-2.18 (m, 2 H) 2.41 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.58 - 3.67 (m, 2 H) 3.75 - 3.84 (m, 2 H) 4.02

(t, J=7.26 Hz, 2 H) 4.43 (dd, J=7.92, 4.88 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.78 Hz, 2 H) 6.94 (d, J=8.67 Hz, 2 H) 7.12 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.49 (d, J=8.46 Hz, 4 H)

9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 37 Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate

...............desired

Example 37A (S)-2,5-dioxopyrrolidin-1-yl 2-(methoxycarbonylamino)-3-methylbutanoate To a mixture of (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (19.66 g, 112 mmol) and N-hydroxysuccinimide (13.29g, 116 mmol) was added ethyl acetate (250 ml), and the mixture was cooled to 0-5 °C. Diisopropylcarbodiimide (13.88 g, 110 mmol) was added and the reaction mixture was stirred at 0-5 °C for about 1 hour. The reaction mixture was warmed to room temperature. The solids (diisopropylurea by-product) were filtered and rinsed with ethyl acetate. The filtrate was concentrated in vacuo to an oil. Isopropyl alcohol (200 ml) was added to the oil and the mixture was heated to about 50 °C to obtain a homogeneous solution. Upon cooling, crystalline solids formed. The solids were filtered and washed with isopropyl alcohol (3 x 20 ml) and dried to give the title compound as a white solid (23.2 g, 77% yield).

Example 37B

(S)- 1 -((S)-2-(methoxycarbonylamino)-3-methylbutanoyl)pyrrolidine-2-carboxylic acid To a mixture of L-proline (4.44g, 38.6 mmol), water (20 ml), acetonitrile (20 ml) and DIEA (9.5 g, 73.5 mmol) was added a solution of the product from Example 37A (1Og, 36.7 mmol) in acetonitrile (20 inL) over 10 minutes. The reaction mixture was stirred overnight at room temperature. The solution was concentrated under vacuum to remove the acetonitrile. To the resulting clear water solution was added 6N HCl (9 ml) until pH ~ 2 .The solution was transferred to a separatory funnel and 25% NaCl (10 ml) was added and the mixture was extracted with ethyl acetate (75 ml), and then again with ethyl acetate (6 x 20 ml), and the combined extracts were washed with 25% NaCl (2 x 10ml). The solvent was evaporated to give a thick oil. Heptane was added and the solvent was evaporated to give a foam, which was dried under high vacuum. Diethyl ether was added and the solvent was evaporated to give a foam, which was dried under high vacuum to give the title compound (10.67g) as a white solid.

The compound of Example 37B can also be prepreared according to the following procedure: To a flask was charged L- valine (35 g, 299 mmol), IN sodium hydroxide solution (526 ml,

526 mmol) and sodium carbonate (17.42 g, 164 mmol). The mixture was stirred for 15 min to dissolve solids and then cooled to 15 °C. Methyl chloroformate (29.6 g, 314 mmol) was added slowly to the reaction mixture. The mixture was then stirred at rt for 30 min. The mixture was cooled to 15 °C and pH adjusted to -5.0 with concentrated HCl solution. 100 inL of 2-methytetrahydrofuran (2- MeTHF) was added and the adjustment of pH continued until the pH reached ~ 2.0. 150 mL of 2- MeTHF was added and the mixture was stirred for 15 min. Layers were separated and the aqueous layer extracted with 100 mL of 2-MeTHF. The combined organic layer was dried over anhyd Na₂SC^ and filtered, and Na₂SC^ cake was washed with 50 mL of 2-MeTHF. The product solution was concentrated to ~ 100 mL, chased with 120 mL of IPAc twice. 250 mL of heptanes was charged slowly and then the volume of the mixture was concentrated to 300 mL. The mixture was heated to 45 °C and 160 mL of heptanes charged. The mixture was cooled to rt in 2h, stirred for 30 min, filtered and washed with 2-MeTHF/heptanes mixture (1:7, 80 inL). The wetcake was dried at 55 °C for 24 h to give 47.1 g of Moc-L- VaI-OH product as a white solid (90%).

Moc-L- VaI-OH (15O g, 856 mmol), HOBt hydrate (138 g, 899 mmol) and DMF (1500 ml) were charged to a flask. The mixture was stirred for 15 min to give a clear solution. EDC hydrochloride (172 g, 899 mmol) was charged and mixed for 20 min. The mixture was cooled to 13

°C and (L)-proline benzyl ester hydrochloride (207 g, 856 mmol) charged. Triethylamine (109 g,

1079 mmol) was then charged in 30 min. The resulting suspension was mixed at rt for 1.5 h. The reaction mixture was cooled to 15 °C and 1500 mL of 6.7% NaHCO₃ charged in 1.5 h, followed by the addition of 1200 mL of water over 60 min. The mixture was stirred at rt for 30 min, filtered and washed with water/DMF mixture (1 :2, 250 mL) and then with water (1500 mL). The wetcake was dried at 55 °C for 24 h to give 282 g of product as a white solid (90%).

The resulting solids (40 g) and 5% Pd/ Alumina were charged to a Parr reactor followed by THF (160 mL). The reactor was sealed and purged with nitrogen (6 x 20 psig) followed by a hydrogen purge (6 x 30 psig). The reactor was pressurized to 30 psig with hydrogen and agitated at room temperature for approximately 15 hours. The resulting slurry was filtered through a GF/F filter and concentrated to approximately 135 g solution. Heptane was added (120 mL), and the solution was stirred until solids formed. After an addition 2 - 3 hours additional heptane was added drop-wise (240 mL), the slurry was stirred for approximately 1 hour, then filtered. The solids were dried to afford the title compound.

Example 37C

(lR,4R)-1,4-bis(4-nitrophenyl)butane-1,4-diyl dimethanesulfonate

The product from Example 32 (5.01 g, 13.39 mmol) was combined with 2- methyltetrahydrofuran (70 mL) and cooled to -5 °C, and N,N-diisopropylethylamine (6.81 g, 52.7 mmol) was added over 30 seconds. Separately, a solution of methanesulfonic anhydride (6.01 g, 34.5 mmol) in 2-methyltetrahydrofuran (30 mL) was prepared and added to the diol slurry over 3 min., maintaining the internal temperature between -15 °C and -25 °C. After mixing for 5 min at -15 °C, the cooling bath was removed and the reaction was allowed to warm slowly to 23 °C and mixed for 30 minutes. After reaction completion, the crude slurry was carried immediately into the next step.

Example 37D

(2S,5S)-1-(4-tert-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine

To the crude product solution from Example 37C (7.35 g, 13.39 mmol) was added 4-tert- butylaniline (13.4 g, 90 mmol) at 23 °C over 1 minute. The reaction was heated to 65 °C for 2 h. After completion, the reaction mixture was cooled to 23 °C and diluted with 2-methyltetrahydrofuran (100 mL) and 1 M HCl (150 mL). After partitioning the phases, the organic phase was treated with 1 M HCl (140 mL), 2-methyltetrahydrofuran (50 mL), and 25 wt% aq. NaCl (100 mL), and the phases were partitioned. The organic phase was washed with 25 wt% aq. NaCl (50 mL), dried over MgSO/_t, filtered, and concentrated in vacuo to approximately 20 mL. Heptane (30 mL) and additional 2- methyltetrahydrofuran were added in order to induce crystallization. The slurry was concentrated further, and additional heptane (40 mL) was slowly added and the slurry was filtered, washing with 2- methyltetrahydrofuran:heptane (1:4, 20 mL). The solids were suspended in MeOH (46 mL) for 3 h, filtered, and the wet solid was washed with additional MeOH (18 mL). The solid was dried at 45 °C in a vacuum oven for 16 h to provide the title compound (3.08 g, 51% 2-step yield).

Example 37E

4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline

To a 160 ml Parr stirrer hydrogenation vessel was added the product from Example 37D (2 g, 4.49 mmol), followed by 60 ml of THF, and Raney Nickel Grace 2800 (1 g, 50 wt% (dry basis)) under a stream of nitrogen. The reactor was assembled and purged with nitrogen (8 x 20 psig) followed by purging with hydrogen (8 x 30 psig). The reactor was then pressurized to 30 psig with hydrogen and agitation (700 rpm) began and continued for a total of 16 h at room temperature. The slurry was filtered by vacuum filtration using a GF/F Whatman glass fiber filter. Evaporation of the filtrate to afford a slurry followed by the addition heptane and filtration gave the crude title compound, which was dried and used directly in the next step.

Example 37F dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4, l- phenylene)bis(azanediyl)bis(oxomethylene))bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diy 1) die arb amate To a solution of the product from Example 37E (1.64 g, 4.25 mmol) in DMF (20 ml), the product from Example 37B (2.89 g, 10.63 mmol), and HATU (4.04 g, 10.63 mmol) in DMF (15OmL) was added triethylamine (1.07 g, 10.63 mmol), and the solution was stirred at room temperature for 90 min. To the reaction mixture was poured 20 mL of water, and the white precipitate obtained was filtered, and the solid was washed with water (3x5 mL). The solid was blow dried for Ih. The crude material was loaded on a silica gel column and eluted with a gradient starting with ethyl acetate/ heptane (3/7), and ending with pure ethyl acetate. The desired fractions were combined and solvent distilled off to give a very light yellow solid, which was dried at 45 °C in a vacuum oven with nitrogen purge for 15 h to give the title compound (2.3 g, 61% yield). ¹H NMR (400 MHz, DMSO- D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 - 2.04 (m, 8 H) 2.09 - 2.19 (m, 2 H) 2.44 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 - 3.66 (m, 2 H) 3.77 - 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H).

Alternately, the product from example 37E (11.7 g, 85 wt%, 25.8 mmol) and the product from example 37B (15.45 g, 56.7 mmol) are suspended in EtOAc (117 mL), diisopropylethylamine (18.67 g, 144 mmol) is added and the solution is cooled to 0 °C. In a separate flask, 1-propanephosphonic acid cyclic anhydride (T3P^®) (46.0 g, 50 wt% in EtOAc, 72.2 mmol) was dissolved in EtOAc (58.5 mL), and charged to an addition funnel. The T₃P solution is added to the reaction mixture drop-wise over 3-4 h and stirred until the reaction is complete. The reaction is warmed to room temperature,and washed with IM HCl/7.5 wt% NaCl (100 mL), then washed with 5% NaHCO₃ (100 mL), then washed with 5% NaCl solution (100 mL). The solution was concentrated to approximately 60 mL, EtOH (300 mL) was added, and the solution was concentrated to 84 g solution.

A portion of the EtOH solution of product (29 g) was heated to 40 °C, and added 134 g 40 w% EtOH in H₂O. A slurry of seeds in 58 wt/wt% EtOH/H₂O was added, allowed to stir at 40 °C for several hours, then cooled to 0 °C. The slurry is then filtered, and washed with 58wt/wt% EtOH/H₂O. The product is dried at 40 - 60 °C under vacuum, and then rehydrated by placing a tray of water in the vacuum oven to give the title compound. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

.................

http://www.google.com/patents/EP2337781A2?cl=en

Example 34

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate and

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-ter/'-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

Example 34A l-(4-fer?-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine The product from Example 1C (3.67 g, 7.51 mmol) and 4-tert-butylaniline (11.86 ml, 75 mmol) in DMF (40 ml) was stirred under nitrogen at 50 °C for 4 h. The resulting mixture was diluted into ethyl acetate, treated with IM HCl, stirred for 10 minutes and filtered to remove solids. The filtrate organic layer was washed twice with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (5% to 30%) to give a solid. The solid was triturated in a minimal volume of 1 :9 ethyl acetate/hexane to give a light yellow solid as a mixture of trans and cis isomers (1.21 g, 36%).

Example 34B 4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline and 4,4'-((2R,5R)-1-(4-fert- butylphenyl)pyrrolidine-2,5-diyl)dianiline To a solution of the product from Example 34A (1.1 g, 2.47 mmol) in ethanol (20 ml) and

THF (20 ml) was added PtC>₂ (0.22 g, 0.97 mmol) in a 50 ml pressure bottle and stirred under 30 psi hydrogen at room temperature for 1 h. The mixture was filtered through a nylon membrane and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (20% to 60%). The title compound eluted as the first of 2 stereoisomers (trans isomer, 0.51 g, 54%).

Example 34C

(2S,2'S)-tert-Butyl 2,2'-(4,4'-((2S,5S)-1-(4-fer/'-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine- 1 -carboxylate and (2S,2'S)-tert-Butyl 2,2'- (4,4'-((2R,5R)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine-1-carboxylate To a mixture of the product from Example 34B (250 mg, 0.648 mmol), (S)-1-(tert- butoxycarbonyl)pyrrolidine-2-carboxylic acid (307 mg, 1.427 mmol) and HATU (542 mg, 1.427 mmol) in DMSO (10 ml) was added Hunig's base (0.453 ml, 2.59 mmol). The reaction mixture was stirred at room temperature for 1 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (10% to 50%) to give the title compound (500 mg, 99%).

Example 34D

(2S,2'S)-N,N'-(4,4'-((2S,5S)-1-(4-ter/'-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))dipyrrolidine-2-carboxamide and (2S,2'S)-N,N'-(4,4'-((2R,5R)-1-(4-tert- butylphenyl)pyrrolidine-2,5-diyl)bis(4,l-phenylene))dipyrrolidine-2-carboxamide To the product from Example 34C (498 mg, 0.638 mmol) in dichloromethane (4 ml) was added TFA (6 ml). The reaction mixture was stirred at room temperature for 1 h and concentrated in vacuo. The residue was partitioned between 3: 1 CHCl₃dsopropyl alcohol and saturated aq. NaHCO₃. The aqueous layer was extracted by 3: 1 CHCl₃:isopropyl alcohol again. The combined organic layers were dried over

filtered and concentrated to give the title compound (345 mg, 93%).

Example 34E Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate and

Dimethyl (2S,2'S)-1, r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34D (29.0 mg, 0.050 mmol), (S)-2-(methoxycarbonylamino)-3- methylbutanoic acid (19.27 mg, 0.110 mmol), EDAC (21.09 mg, 0.110 mmol), HOBT (16.85 mg,

0.110 mmol) and N-methylmorpholine (0.027 ml, 0.250 mmol) were combined in DMF (2 ml). The reaction mixture was stirred at room temperature for 3 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine twice, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (50% to 80%) to give a solid. The solid was triturated with ethyl acetate/hexane to give the title compound (13 mg, 29%). ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.85 - 0.95 (m, 12 H) 1.11 (s, 9 H) 1.59 - 1.65 (m, 2 H) 1.79 - 2.04 (m, 8 H) 2.10 - 2.18 (m, 2 H) 2.41-2.46 (m, 2H) 3.52 (s, 6 H)

3.57 - 3.67 (m, 2 H) 3.76 - 3.86 (m, 2 H) 4.00 (t, J=7.56 Hz, 2 H) 4.39 - 4.46 (m, 2 H) 5.15 (d, J=7.00

Hz, 2 H) 6.17 (d, J=7.70 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=7.37 Hz, 4 H) 7.30 (d, J=8.20

Hz, 2 H) 7.50 (d, J=8.24 Hz, 4 H) 9.98 (s, 2 H); (ESI+) m/z 895 (M+H)+. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 35

Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate

.............desired

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the first of the 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 - 2.04 (m, 8 H) 2.09 - 2.19 (m, 2 H) 2.44 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 - 3.66 (m, 2 H) 3.77 - 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV Ib- Conl replicon assays in the presence of 5% FBS.

Example 36 Dimethyl (2S,2'S)-1, r-((2S,2'S)-2,2'-(4,4'-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 - oxobutane-2, 1 -diyl)dicarbamate

..........undesired

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the second of 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.87

(d, J=6.51 Hz, 6 H) 0.92 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.53 Hz, 2 H) 1.82 - 2.04 (m, 8

H) 2.09-2.18 (m, 2 H) 2.41 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.58 - 3.67 (m, 2 H) 3.75 - 3.84 (m, 2 H) 4.02

(t, J=7.26 Hz, 2 H) 4.43 (dd, J=7.92, 4.88 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.78 Hz, 2 H) 6.94 (d, J=8.67 Hz, 2 H) 7.12 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.49 (d, J=8.46 Hz, 4 H)

9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 37 Dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diyl)dicarbamate

..................desired

Example 37A (S)-2,5-dioxopyrrolidin-1-yl 2-(methoxycarbonylamino)-3-methylbutanoate To a mixture of (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (19.66 g, 112 mmol) and N-hydroxysuccinimide (13.29g, 116 mmol) was added ethyl acetate (250 ml), and the mixture was cooled to 0-5 °C. Diisopropylcarbodiimide (13.88 g, 110 mmol) was added and the reaction mixture was stirred at 0-5 °C for about 1 hour. The reaction mixture was warmed to room temperature. The solids (diisopropylurea by-product) were filtered and rinsed with ethyl acetate. The filtrate was concentrated in vacuo to an oil. Isopropyl alcohol (200 ml) was added to the oil and the mixture was heated to about 50 °C to obtain a homogeneous solution. Upon cooling, crystalline solids formed. The solids were filtered and washed with isopropyl alcohol (3 x 20 ml) and dried to give the title compound as a white solid (23.2 g, 77% yield).

Example 37B

(S)- 1 -((S)-2-(methoxycarbonylamino)-3-methylbutanoyl)pyrrolidine-2-carboxylic acid To a mixture of L-proline (4.44g, 38.6 mmol), water (20 ml), acetonitrile (20 ml) and DIEA (9.5 g, 73.5 mmol) was added a solution of the product from Example 37A (1Og, 36.7 mmol) in acetonitrile (20 inL) over 10 minutes. The reaction mixture was stirred overnight at room temperature. The solution was concentrated under vacuum to remove the acetonitrile. To the resulting clear water solution was added 6N HCl (9 ml) until pH ~ 2 .The solution was transferred to a separatory funnel and 25% NaCl (10 ml) was added and the mixture was extracted with ethyl acetate (75 ml), and then again with ethyl acetate (6 x 20 ml), and the combined extracts were washed with 25% NaCl (2 x 10ml). The solvent was evaporated to give a thick oil. Heptane was added and the solvent was evaporated to give a foam, which was dried under high vacuum. Diethyl ether was added and the solvent was evaporated to give a foam, which was dried under high vacuum to give the title compound (10.67g) as a white solid.

The compound of Example 37B can also be prepreared according to the following procedure: To a flask was charged L- valine (35 g, 299 mmol), IN sodium hydroxide solution (526 ml,

526 mmol) and sodium carbonate (17.42 g, 164 mmol). The mixture was stirred for 15 min to dissolve solids and then cooled to 15 °C. Methyl chloroformate (29.6 g, 314 mmol) was added slowly to the reaction mixture. The mixture was then stirred at rt for 30 min. The mixture was cooled to 15 °C and pH adjusted to -5.0 with concentrated HCl solution. 100 inL of 2-methytetrahydrofuran (2- MeTHF) was added and the adjustment of pH continued until the pH reached ~ 2.0. 150 mL of 2- MeTHF was added and the mixture was stirred for 15 min. Layers were separated and the aqueous layer extracted with 100 mL of 2-MeTHF. The combined organic layer was dried over anhyd Na₂SC^ and filtered, and Na₂SC^ cake was washed with 50 mL of 2-MeTHF. The product solution was concentrated to ~ 100 mL, chased with 120 mL of IPAc twice. 250 mL of heptanes was charged slowly and then the volume of the mixture was concentrated to 300 mL. The mixture was heated to 45 °C and 160 mL of heptanes charged. The mixture was cooled to rt in 2h, stirred for 30 min, filtered and washed with 2-MeTHF/heptanes mixture (1:7, 80 inL). The wetcake was dried at 55 °C for 24 h to give 47.1 g of Moc-L- VaI-OH product as a white solid (90%).

Moc-L- VaI-OH (15O g, 856 mmol), HOBt hydrate (138 g, 899 mmol) and DMF (1500 ml) were charged to a flask. The mixture was stirred for 15 min to give a clear solution. EDC hydrochloride (172 g, 899 mmol) was charged and mixed for 20 min. The mixture was cooled to 13

°C and (L)-proline benzyl ester hydrochloride (207 g, 856 mmol) charged. Triethylamine (109 g,

1079 mmol) was then charged in 30 min. The resulting suspension was mixed at rt for 1.5 h. The reaction mixture was cooled to 15 °C and 1500 mL of 6.7% NaHCO₃ charged in 1.5 h, followed by the addition of 1200 mL of water over 60 min. The mixture was stirred at rt for 30 min, filtered and washed with water/DMF mixture (1 :2, 250 mL) and then with water (1500 mL). The wetcake was dried at 55 °C for 24 h to give 282 g of product as a white solid (90%).

The resulting solids (40 g) and 5% Pd/ Alumina were charged to a Parr reactor followed by THF (160 mL). The reactor was sealed and purged with nitrogen (6 x 20 psig) followed by a hydrogen purge (6 x 30 psig). The reactor was pressurized to 30 psig with hydrogen and agitated at room temperature for approximately 15 hours. The resulting slurry was filtered through a GF/F filter and concentrated to approximately 135 g solution. Heptane was added (120 mL), and the solution was stirred until solids formed. After an addition 2 - 3 hours additional heptane was added drop-wise (240 mL), the slurry was stirred for approximately 1 hour, then filtered. The solids were dried to afford the title compound.

Example 37C

(lR,4R)-1,4-bis(4-nitrophenyl)butane-1,4-diyl dimethanesulfonate

The product from Example 32 (5.01 g, 13.39 mmol) was combined with 2- methyltetrahydrofuran (70 mL) and cooled to -5 °C, and N,N-diisopropylethylamine (6.81 g, 52.7 mmol) was added over 30 seconds. Separately, a solution of methanesulfonic anhydride (6.01 g, 34.5 mmol) in 2-methyltetrahydrofuran (30 mL) was prepared and added to the diol slurry over 3 min., maintaining the internal temperature between -15 °C and -25 °C. After mixing for 5 min at -15 °C, the cooling bath was removed and the reaction was allowed to warm slowly to 23 °C and mixed for 30 minutes. After reaction completion, the crude slurry was carried immediately into the next step.

Example 37D

(2S,5S)-1-(4-tert-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine

To the crude product solution from Example 37C (7.35 g, 13.39 mmol) was added 4-tert- butylaniline (13.4 g, 90 mmol) at 23 °C over 1 minute. The reaction was heated to 65 °C for 2 h. After completion, the reaction mixture was cooled to 23 °C and diluted with 2-methyltetrahydrofuran (100 mL) and 1 M HCl (150 mL). After partitioning the phases, the organic phase was treated with 1 M HCl (140 mL), 2-methyltetrahydrofuran (50 mL), and 25 wt% aq. NaCl (100 mL), and the phases were partitioned. The organic phase was washed with 25 wt% aq. NaCl (50 mL), dried over MgSO/_t, filtered, and concentrated in vacuo to approximately 20 mL. Heptane (30 mL) and additional 2- methyltetrahydrofuran were added in order to induce crystallization. The slurry was concentrated further, and additional heptane (40 mL) was slowly added and the slurry was filtered, washing with 2- methyltetrahydrofuran:heptane (1:4, 20 mL). The solids were suspended in MeOH (46 mL) for 3 h, filtered, and the wet solid was washed with additional MeOH (18 mL). The solid was dried at 45 °C in a vacuum oven for 16 h to provide the title compound (3.08 g, 51% 2-step yield).

Example 37E

4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline

To a 160 ml Parr stirrer hydrogenation vessel was added the product from Example 37D (2 g, 4.49 mmol), followed by 60 ml of THF, and Raney Nickel Grace 2800 (1 g, 50 wt% (dry basis)) under a stream of nitrogen. The reactor was assembled and purged with nitrogen (8 x 20 psig) followed by purging with hydrogen (8 x 30 psig). The reactor was then pressurized to 30 psig with hydrogen and agitation (700 rpm) began and continued for a total of 16 h at room temperature. The slurry was filtered by vacuum filtration using a GF/F Whatman glass fiber filter. Evaporation of the filtrate to afford a slurry followed by the addition heptane and filtration gave the crude title compound, which was dried and used directly in the next step.

Example 37F dimethyl (2S,2'S)-l,r-((2S,2'S)-2,2'-(4,4'-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4, l- phenylene)bis(azanediyl)bis(oxomethylene))bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 - diy 1) die arb amate To a solution of the product from Example 37E (1.64 g, 4.25 mmol) in DMF (20 ml), the product from Example 37B (2.89 g, 10.63 mmol), and HATU (4.04 g, 10.63 mmol) in DMF (15OmL) was added triethylamine (1.07 g, 10.63 mmol), and the solution was stirred at room temperature for 90 min. To the reaction mixture was poured 20 mL of water, and the white precipitate obtained was filtered, and the solid was washed with water (3x5 mL). The solid was blow dried for Ih. The crude material was loaded on a silica gel column and eluted with a gradient starting with ethyl acetate/ heptane (3/7), and ending with pure ethyl acetate. The desired fractions were combined and solvent distilled off to give a very light yellow solid, which was dried at 45 °C in a vacuum oven with nitrogen purge for 15 h to give the title compound (2.3 g, 61% yield). ¹H NMR (400 MHz, DMSO- D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 - 2.04 (m, 8 H) 2.09 - 2.19 (m, 2 H) 2.44 - 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 - 3.66 (m, 2 H) 3.77 - 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H).

Alternately, the product from example 37E (11.7 g, 85 wt%, 25.8 mmol) and the product from example 37B (15.45 g, 56.7 mmol) are suspended in EtOAc (117 mL), diisopropylethylamine (18.67 g, 144 mmol) is added and the solution is cooled to 0 °C. In a separate flask, 1-propanephosphonic acid cyclic anhydride (T3P^®) (46.0 g, 50 wt% in EtOAc, 72.2 mmol) was dissolved in EtOAc (58.5 mL), and charged to an addition funnel. The T₃P solution is added to the reaction mixture drop-wise over 3-4 h and stirred until the reaction is complete. The reaction is warmed to room temperature,and washed with IM HCl/7.5 wt% NaCl (100 mL), then washed with 5% NaHCO₃ (100 mL), then washed with 5% NaCl solution (100 mL). The solution was concentrated to approximately 60 mL, EtOH (300 mL) was added, and the solution was concentrated to 84 g solution.

A portion of the EtOH solution of product (29 g) was heated to 40 °C, and added 134 g 40 w% EtOH in H₂O. A slurry of seeds in 58 wt/wt% EtOH/H₂O was added, allowed to stir at 40 °C for several hours, then cooled to 0 °C. The slurry is then filtered, and washed with 58wt/wt% EtOH/H₂O. The product is dried at 40 - 60 °C under vacuum, and then rehydrated by placing a tray of water in the vacuum oven to give the title compound. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

intermediates

Example 32

( 1 R,4R)- 1 ,4-bis(4-mtrophenyl)butane- 1 ,4-diol

To (S)-(-)-α,α-diphenyl-2-pyrrohdinemethanol (2 71 g, 10 70 mmol) was added THF (80 mL) at 23 °C The very thin suspension was treated with t₁₁methyl borate (1 44 g, 13 86 mmol) over 30 seconds, and the resulting solution was mixed at 23 °C for 1 h The solution was cooled to 16-19 °C, and N,N-diethylanilme borane (21 45 g, 132 mmol) was added dropwise via syringe over 3-5 mm (caution vigorous H₂ evolution), while the internal temperature was maintained at 16-19 °C After 15 mm, the H₂ evolution had ceased To a separate vessel was added the product from Example IA (22 04 g, 95 wt%, 63 8 mmol), followed by THF (80 mL), to form an orange slurry After cooling the slurry to 11 °C, the borane solution was transferred via cannula into the dione slurry over 3-5 min During this period, the internal temperature of the slurry rose to 16 °C After the addition was complete, the reaction was maintained at 20-27 °C for an additional 2 5 h After reaction completion, the mixture was cooled to 5 °C and methanol (16 7 g, 521 mmol) was added dropwise over 5-10 mm, maintaining an internal temperature <20 °C (note vigorous H₂ evolution) After the exotherm had ceased (ca 10 mm), the temperature was adjusted to 23 °C, and the reaction was mixed until complete dissolution of the solids had occurred Ethyl acetate (300 mL) and 1 M HCl (120 mL) were added, and the phases were partitioned The organic phase was then washed successively with 1 M HCl (2 x 120 mL), H₂O (65 mL), and 10% aq NaCl (65 mL) The orgamcs were dried over MgSO₄, filtered, and concentrated in vacuo Crystallization of the product occurred during the concentration The slurry was warmed to 50 °C, and heptane (250 inL) was added over 15 min. The slurry was then allowed to mix at 23 °C for 30 min and filtered. The wet cake was washed with 3: 1 heptane:ethyl acetate (75 mL), and the orange, crystalline solids were dried at 45 °C for 24 h to provide the title compound (15.35 g, 99.3% ee, 61% yield), which was contaminated with 11% of the meso isomer (vs. dl isomer).

References

1.  "VIEKIRA PAK™ (ombitasvir, paritaprevir and ritonavir tablets; dasabuvir tablets), for Oral Use. Full Prescribing Information"(PDF). AbbVie Inc., North Chicago, IL 60064. Retrieved 30 July 2015.
2.  "FDA approves Viekira Pak to treat hepatitis C". Food and Drug Administration. December 19, 2014.
3.  "TECHNIVIE™ (ombitasvir, paritaprevir and ritonavir) Tablets, for Oral Use. Full Prescribing Information" (PDF). AbbVie Inc., North Chicago, IL 60064. Retrieved 28 July 2015.
4.  "FDA approves Technivie for treatment of chronic hepatitis C genotype 4". Food and Drug Administration. July 24, 2015.
5.  Jordan J. Feld, Kris V. Kowdley, Eoin Coakley, Samuel Sigal, David R. Nelson, Darrell Crawford, Ola Weiland, Humberto Aguilar, Junyuan Xiong, Tami Pilot-Matias, Barbara DaSilva-Tillmann, Lois Larsen, Thomas Podsadecki, and Barry Bernstein (2014). "Treatment of HCV with ABT-450/r–Ombitasvir and Dasabuvir with Ribavirin". N Engl J Med 370: 1594–1603.doi:10.1056/NEJMoa1315722.

Ombitasvir

Systematic (IUPAC) name
Dimethyl ({(2S,5S)-1-[4-(2-methyl-2-propanyl)phenyl]-2,5-pyrrolidinediyl}bis{4,1-phenylenecarbamoyl(2S)-2,1-pyrrolidinediyl[(2S)-3-methyl-1-oxo-1,2-butanediyl]})biscarbamate
Clinical data
Trade names	Viekira Pak (with ombitasvir, paritaprevir, ritonavir and dasabuvir), Technivie (with ombitasvir, paritaprevir, and ritonavir)
Legal status	US: ℞-only
Routes of administration	Oral
Pharmacokinetic data
Bioavailability	not determined
Protein binding	~99.9%
Metabolism	amide hydrolysis followed by oxidation
Onset of action	~4 to 5 hours
Biological half-life	21 to 25 hours
Excretion	mostly with feces (90.2%)
Identifiers
CAS Registry Number	1258226-87-7
PubChem	CID: 54767916
ChemSpider	31136214
ChEBI	CHEBI:85183
Synonyms	ABT-267
Chemical data
Formula	C50H67N7O8
Molecular mass	894.11 g/mol

rx list

VIEKIRA PAK is ombitasvir, paritaprevir, ritonavir fixed dose combination tablets copackaged with dasabuvir tablets.

Ombitasvir, paritaprevir, ritonavir fixed dose combination tablet includes ahepatitis C virus NS5A inhibitor (ombitasvir), a hepatitis C virus NS3/4Aprotease inhibitor (paritaprevir), and a CYP3A inhibitor (ritonavir) that inhibits CYP3A mediated metabolism of paritaprevir, thereby providing increased plasma concentration of paritaprevir. Dasabuvir is a hepatitis C virus nonnucleoside NS5B palm polymerase inhibitor, which is supplied as separate tablets in the copackage. Both tablets are for oral administration.

Ombitasvir

The chemical name of ombitasvir is Dimethyl ([(2S,5S)-1-(4-tert-butylphenyl) pyrrolidine-2,5diyl]bis{benzene-4,1-diylcarbamoyl(2S)pyrrolidine-2,1-diyl[(2S)-3-methyl-1-oxobutane-1,2diyl]})biscarbamate hydrate. The molecular formula is C₅₀H₆₇N7O₈•4.5H₂O (hydrate) and the molecular weight for the drug substance is 975.20 (hydrate). The drug substance is white to light yellow to light pink powder, and is practically insoluble in aqueous buffers but is soluble in ethanol. Ombitasvir has the following molecular structure:

Paritaprevir

The chemical name of paritaprevir is (2R,6S,12Z,13aS,14aR,16aS)-N-(cyclopropylsulfonyl)-6{[(5-methylpyrazin-2-yl)carbonyl]amino}-5,16-dioxo-2-(phenanthridin-6-yloxy)1,2,3,6,7,8,9,10,11,13a,14,15,16,16a-tetradecahydrocyclopropa[e]pyrrolo[1,2-a][1,4] diazacyclopentadecine-14a(5H)-carboxamide dihydrate. The molecular formula is C₄₀H₄₃N₇O₇S•2H₂O (dihydrate) and the molecular weight for the drug substance is 801.91 (dihydrate). The drug substance is white to off-white powder with very low water solubility. Paritaprevir has the following molecular structure:

Ritonavir

The chemical name of ritonavir is [5S-(5R*,8R*,10R*,11R*)]10-Hydroxy-2-methyl-5-(1methyethyl)-1-[2-(1-methylethyl)-4-thiazolyl]-3,6-dioxo-8,11-bis(phenylmethyl)-2,4,7,12tetraazatridecan-13-oic acid,5-thiazolylmethyl ester. The molecular formula is C₃₇H₄₈N₆O₅S₂ and the molecular weight for the drug substance is 720.95. The drug substance is white to off white to light tan powder practically insoluble in water and freely soluble in methanol and ethanol. Ritonavir has the following molecular structure:

Ombitasvir, Paritaprevir, Ritonavir Fixed-Dose Combination Tablets

Ombitasvir, paritaprevir, and ritonavir film-coated tablets are co-formulated immediate release tablets. The tablet contains copovidone, K value 28,vitamin E polyethylene glycol succinate, propylene glycol monolaurate Type I, sorbitan monolaurate, colloidal silicon dioxide/colloidal anhydrous silica, sodium stearyl fumarate, polyvinyl alcohol, polyethylene glycol 3350/macrogol 3350, talc, titanium dioxide, and iron oxide red. The strength for the tablet is 12.5 mg ombitasvir, 75 mg paritaprevir, 50 mg ritonavir.

Dasabuvir

The chemical name of dasabuvir is Sodium 3-(3-tert-butyl-4-methoxy-5-{6[(methylsulfonyl)amino]naphthalene-2-yl}phenyl)-2,6-dioxo-3,6-dihydro-2H-pyrimidin-1-ide hydrate (1:1:1). The molecular formula is C₂₆H₂₆N₃O₅S•Na•H₂O (salt, hydrate) and the molecular weight of the drug substance is 533.57 (salt, hydrate). The drug substance is white to pale yellow to pink powder, slightly soluble in water and very slightly soluble in methanol and isopropyl alcohol. Dasabuvir has the following molecular structure:

Dasabuvir is formulated as a 250 mg film-coated, immediate release tablet containing microcrystalline cellulose (D50-100 um), microcrystalline cellulose (D50-50 um), lactose monohydrate, copovidone, croscarmellose sodium, colloidal silicon dioxide/anhydrous colloidal silica, magnesium stearate, polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350/macrogol 3350, talc, and iron oxide yellow, iron oxide red and iron oxide black. Each tablet contains 270.3 mg dasabuvir sodium monohydrate equivalent to 250 mg dasabuvir.

//////////fda 2014, Ombitasvir, orphan drug, Abbvie Inc.

Argatroban

ArgatrobanMolecular Formula: C23H36N6O5S
Formula Weight: 508.63
CAS No.: 74863-84-6 

(2R,4R)-1-[(2S)-5-(diaminomethylideneamino)-2-
[[(3R)-3-methyl-1,2,3,4-tetrahydroquinolin-8-yl]
sulfonylamino]pentanoyl]-4-methyl-piperidine-2-
carboxylic acid

PATENT

US 7,589,106, 7,687,516, EP 0008746; US 4258192, US 4201863

Argatroban is an anticoagulant that is a small molecule direct thrombin inhibitor.[1] In 2000, argatroban was licensed by the Food and Drug Administration (FDA) for prophylaxis or treatment of thrombosis in patients with heparin-induced thrombocytopenia (HIT). In 2002, it was approved for use during percutaneous coronary interventions in patients who have HIT or are at risk for developing it. In 2012, it was approved by the MHRA in the UK for anticoagulation in patients with Heparin-Induced Thrombocytopenia Type II (HIT) who require parenteral antithrombotic therapy.[2]

Argatroban is given intravenously and drug plasma concentrations reach steady state in 1-3 hours.[3] Argatroban is metabolized in the liver and has a half-life of about 50 minutes. It is monitored by PTT. Because of its hepatic metabolism, it may be used in patients with renal dysfunction. (This is in contrast to lepirudin, a direct thrombin inhibitor that is primarily renally cleared).

Argatroban is used as an anticoagulant in individuals with thrombosis and heparin induced thrombocytopenia. Often these individuals require long term anticoagulation. If warfarin is chosen as the long term anticoagulant, this poses particular challenges due to the falsely elevated prothrombin time and INR caused by argatroban. The combination of argatroban and warfarin may raise the INR to greater than 5.0 without a significant increased risk of bleeding complications.[4] One solution to this problem is to measure the chromogenic factor X level. A level < 40-45% typically indicates that the INR will be therapeutic (2-3) when the argatroban is discontinued.

 ……………………………………………………….

Argatroban monohydrate

Argatroban is a synthetic direct thrombin inhibitor and the chemical name is 1-[5-[(aminoiminomethyl) amino]-1-oxo2[[(1,2,3,4-tetrahydro-3-methyl-8-quinolinyl)sulfonyl]amino]pentyl]-4-methyl-2- piperidinecarboxylic acid, monohydrate. Argatroban has 4 asymmetric carbons. One of the asymmetric carbons has an R configuration (stereoisomer Type I) and an S configuration (stereoisomer Type II). Argatroban consists of a mixture of R and S stereoisomers at a ratio of approximately 65:35.

The molecular formula of argatroban is C23H36N6O5S•H2O. Its molecular weight is 526.66 g/mol. cas 141396-28-3

Argipidine, Argatroban monohydrate, GN1600, DK-7419, MDI-805 Acova, Slonnon, Novastan

Mitsubishi Chemical (Originator), Encysive Pharmaceuticals (Licensee), Mitsubishi Pharma (Distributor), Daiichi Pharmaceutical (Codevelopment), GlaxoSmithKline (Codevelopment), Mitsubishi Pharma (Codevelopment), Sanofi-SynthLabo (Codevelopment)

Antithrombocytopenic, CARDIOVASCULAR DRUGS, Cerebrovascular Diseases, Treatment of, HEMATOLOGIC DRUGS, Hematopoiesis Disorders Therapy, Ischemic Stroke, Treatment of, NEUROLOGIC DRUGS, Peripheral Vascular Disease, Treatment of, Stroke, Treatment of, Treatment of Peripheral Obstructive Vascular Disease, Thrombin Inhibitors

Synthesis of argatroban on the method reported in the literature there are two synthetic routes, patent EP8746, US4258192, US4201863, JP8115267 relates to a route is: with 4 – methyl-piperidine as a starting material was prepared first intermediate body (2R, 4R) -4 – methyl-2 – ethyl-piperidine, and the first and a t-BOC protected amino nitro-L-arginine condensation, and then the 3 – methyl – 8 – quinoline sulfonyl chloride condensation after hydrolysis, hydrogenation, hydration be argatroban. This entry route synthesis process complicated procedure to be carried out under the protection of nitrogen, the raw material is highly toxic gas phosgene, the operation more difficult.

US4117127, JP02-212473, EP823430, EP8746, JC S Perk Transl 1981 (5), JP02-212473 relates to an alternative route is: nitro L-arginine prior to the 3 – methyl-8 – subsequent condensation quinoline sulfonyl chloride Intermediate (2R, 4R) -4 – methyl-2 – piperidinecarboxylate condensation, and then after hydrolysis, hydrogenation, hydration be argatroban. This synthetic route despite the relatively simple process method, to obtain raw materials, but this method using reagents such as phosphorus oxychloride, phosphorus trichloride has a pungent odor, easy to absorb moisture in humid air, intense smoke, environmental pollution, greater stimulation of the body’s respiratory tract, can cause eye and skin irritation and burning, and the use of this method, complex operation, low yield, high cost.

Patent CN100586946C Argatroban discloses a method for separating optically active isomeric compounds, the feedstock argatroban mixed solvent of alcohol and water was heated to reflux 5-10 hours, cooled and allowed to stand, and filtered to give White crystalline product, dried, repeated 2-6 times. [0008] Patent CN101033223A discloses a Argatroban is the main by-product (2R, 4R)-l_ [N2-(3_ methyl-8 – quinolinesulfonyl)-L-arginyl] -4 – methyl-2 – carboxylic acid, argatroban, and the byproducts are difficult to isolate, argatroban two diastereomeric isomer 21 (S) and 21 (R) separation of work attracted a lot of research persons. Because both physical and chemical properties are very similar, so separation is very difficult. 1993 Rawson, Thomas E.; VanGorp, Kimmie A.; Yang, Janet so first by high pressure liquid chromatography and column chromatography separation to obtain a single 21 (S) and 21 (R) argatroban [ Journal of Pharmaceutical Sciences vol. 82, No. 6,672]; Thibaudeau Karen et al. reported Protein A chromatographic separation [US6440417]. However, due to the separation of these methods a small amount of low efficiency, so there is no practical value industrialization. 2006 China Tianjin Weijie Technology Co., Ltd. Song Honghai et al. Reported using recrystallization Separation 21 (S) and 21 (R) argatroban way [0 With 951,936 it], so that the mass 21 (5) Aga music classes as possible, but the law of low yield, complicated operation, high cost, and a large amount of a small amount of 21 (S) of 21 (R)-product argatroban, from the viewpoint of industrial production, is still a ideal method. [0009] These methods can be effectively prepared argatroban, but the purity of the desired product is not high, poor color, content is low, affecting the quality of the results of its preparation.

U.S. Pat. No. 4,201,863 (6 May 1980) and EP 8746 (filed on 22 Aug. 1979 with priority based on the application for the cited US patent) describe a class of N2-arylsulphonyl-L-argininamide drugs, with anti-thrombotic activity, and the processes for obtaining them. Of these, the compound 4-methyl-1-[N2-(3-methyl-1,2,3,4-tetrahydro-8-quinolinesulphonyl)-L-arginyl]-2-piperidine carboxylic acid (argatroban, isomers mixture) is described. The described process comprises the synthesis of an intermediate NG-substituted-N2-quinolinesulphonyl-L-argininamide from which the desired compound is obtained by catalyzed hydrogenolysis or acidolysis and catalyzed hydrogenation. The general conditions provided for the hydrogenolysis and hydrogenation reaction are: i) inert solvents (methanol, ethanol, tetrahydrofuran or dioxane); ii) presence of a catalyst (Raney nickel, palladium, platinum, ruthenium, rhodium); iii) hydrogen atmosphere at a pressure between 1 and 100 kg/cm2 and preferably between 5 and 50 kg/cm2; iv) temperature between 0° C. and 200° C. and preferably between 50° C. and 150° C.; v) reaction temperature from 2 hours to 120 hours. The crude product obtained is then purified by trituration or by re-crystallization from diethyl ether-tetrahydrofuran, diethyl ether-methanol or from water-methanol or by chromatography. No example is given of this purification step. In particular, both U.S. Pat. No. 4,210,863 and EP 8746 in example 1(E) describe the preparation of argatroban, isomers mixture. This compound is obtained in amorphous form by hydrogenation of [NG-nitro-N2-(3-methyl-8-quinolinesulphonyl)-L-arginyl]-4-methyl-2-piperidine carboxylic acid in ethanol in the presence of Pd/C with hydrogen pressure of 10 kg/cm2 at 100° C. for 8 hours. The catalyst is removed by filtration of the ethanol solution which is then evaporated without further purification and/or re-crystallization steps. In the US patent at issue as indeed in patent application EP 8746, no mention is made of polymorphic forms of the compounds and, for the obtained compound, the following characteristics are reported: Amorphous solid, I.R. (KBr) (cm−1) 3400; 1620; 1460; 1380; Molecular composition (%): theoretical C 54.31; H 7.13; N 16.52; found (%) C 54.01; H 6.98; N 16.61.

U.S. Pat. No. 4,258,192 (24 Mar. 1981) (continuation-in-part of the aforesaid patent application U.S. Pat. No. 4,201,863) and the same patent application EP 8746 describe the stereoisomers and the preparation thereof, including argatroban used as an active principle in medicaments, i.e. the stereoisomer (2R,4R)-4methyl-[4N2-(3-methyl-1,2,3,4-tetrahydro-8-quinolinesulphonyl)-L-arginyl]-2-piperidine carboxylic acid, with the following characteristics: melting point (m.p.). 188-191° C.; I.R. (KBr) (cm−1) 3400, 1620, 1460, 1380; Molecular composition (%): theoretical C 54.31; H 7.13; N 16.52; found (%) C 54.05; H 6.94; N 16.65. The compound is prepared according to the description given in examples 1(E) in U.S. Pat. No. 4,258,192 and 2(E) and 3 in EP 8746 respectively by hydrogenation of (2R,4R) 1-[NG-nitro-N2-(3-methyl-1,2,3,4-tetrahydro-8-quinolinesulphonyl)-L-arginyl]-2-piperidine carboxylic acid in ethanol in presence of acetic acid catalyzed by Pd/C. After filtering the mass to remove the catalyst, the solvent is evaporated and the residue suspended in chloroform, the solution treated with a saturated sodium bicarbonate solution or 1N sodium hydroxide solution and after washing, the solvent is evaporated. The compound is then re-crystallized from ethanol. Again in this case, no reference is made to the obtainment of monohydrate polymorphic forms.

Said polymorphic forms are described instead in the publication Biochem. Biophys. Res. Comm. 1981, 101, 440-446 in the context of stereoisomer preparation. The monohydrate polymorph of the (2R,4R) stereoisomer is prepared by re-crystallization from ethanol/water and the reported characteristics are: m.p. 176-180° C.; [α]D 27 +76.1° (c 1, 0.2N HCl).

U.S. Pat. No. 5,925,760 (20 Jul. 1999) and EP 0823430 (filed 4 Aug. 1997) subsequently describe a new method for preparing argatroban by means of a new intermediate N2-(3-methyl-8-quinolinesulphonyl)-NG-nitro-L-arginine. In particular the patent makes reference to the preparation of a crystalline monohydrate form of argatroban, referring back to examples (D) and (E) of Japanese patent publication No. (Hei)-2-31055/1990 and generically to an I.R. spectrum identical to that of the commercially available argatroban compound. The relevant example in the cited patent publication is example (E), while example (D) concerns the preparation of (2R,4R)-1-[NG-nitro-N2-(3-methyl-8-quinolinesulphonyl)-L-arginyl]-4-methyl-2-piperidine carboxylic acid. This compound represents the starting compound for argatroban preparation by catalytic reduction in the presence of Pd/C. The crude argatroban obtained is then purified by extraction with chloroform, treatment with a saturated sodium bicarbonate solution and, after solvent evaporation, re-crystallization from ethanol or from 15% alcohol in water. It should be noted however that the Japanese patent makes no mention of the monohydrate form of argatroban being obtained and that for the compound the following characteristics are reported: m.p. 188-191° C.; molecular composition (theoretical/found) (%): C 54.31/54.01; H 7.13/6.98; N 16.52/16.61; I.R. (KBr) (cm−1) 3400; 1620; 1460; 1380. These analytical data, with the exception of the unreported melting point, are the same as those indicated in the cited patent documents describing a mixture of (2R,4R)-4methyl-[4N2-(3S-methyl-1,2,3,4-tetrahydro-8-quinolinesulphonyl)-L-arginyl]-2-piperidine carboxylic acid and (2R,4R)-4methyl-1-[N2-(3R-methyl-1,2,3,4-tetrahydro-8-quinolinesulphonyl)-L-arginyl]-2-piperidine carboxylic acid isomers of argatroban, but do not correspond to the melting point given in the publication, being the only document that identifies the monohydrate form of argatroban.

More recently, patent application CN 1,951,937 (filing date 10 Nov. 2006) described a method for preparing hydrated argatroban by treating argatroban with large quantities of water (more than 60 and up to 80 volumes of distilled water per gram of argatroban) at a temperature of 80-100° C. for a time of 0.5-1 hour and crystallization by cooling. The water content reported is comprised between 3.3 and 3.8% and the ratio of dextroisomer R to levoisomer S is R:S=63-67: 37-33.

Argatroban is a compound of wide therapeutic use, for which reason the need still exists to provide a compound of pharmaceutically acceptable quality obtained by easily industrialized and economically convenient methods. With regard to the monohydrate, this form is preferable for the applicative purpose since the anhydrous form is unstable and tends to become hydrated and/or wet. Moreover it crystallizes only with difficulty at the correct ratio between the diastereoisomers.

…..

the protection of 4-methylpiperidine (I) with (Boc)2O gives the carbamate (II), which is condensed with benzyl chloroformate by means of sec-butyl lithium and TMEDA in ethyl ether to yield (?-trans-1-(tert-butoxycarbonyl)-4-methylpiperidine-2-carboxylic acid benzyl ester (III). Deprotection of the NH group of (III) with HCl in ethyl acetate affords (?-trans-4-methylpiperidine-2-carboxylic acid benzyl ester (IV), which is condensed with the protected arginine derivative (V) by means of isobutyl chloroformate and TEA to provide the corresponding amide as a diastereomeric mixture. Resolution of this mixture by flash chromatography furnishes the desired diastereomer (VI), which is treated with HCl in ethyl acetate in order to remove the Boc-protecting group to yield compound (VII). Condensation of compound (VII) with 3-methylquinoline-8-sulfonyl chloride (VIII) by means of TEA in dichloromethane affords the expected sulfonamide (IX). Finally, this compound is submitted to hydrogenation with H2 over Pd/C in AcOH/ethanol in order to produce debenzylation, cleavage of the NO2 group and hydrogenation of the pyridine ring to yield argatroban.

………….

Argatroban, i.e., (2R,4R)-1-((2S)-5-((Aminoiminomethyl)amino)-1-oxo-2-((1,2,3,4-tetrahydro-3-methyl-8-quinolinyl)sulfonyl)amino) pentyl)-4-methyl-2-piperidine carboxylic acid, has two diastereoisomers: 21(R) and 21(S). Usually the ratio of 21(R) to 21(S) is 64-65: 36-35 (U.S. Pat. No. 6,440,417, Cossy. J., et al, Bioorganic & Medicine Chemistry Letters, 11 (2001), 1989-1992, Journal of pharmaceutical Sciences, Vol. 82, No. 6, 672 (1993)).

The structure formula of Argatroban is reported below:

• • 21(S) Argatroban, X=CH3, Y═H;
  • 21(R) Argatroban, X=H, Y=CH3;
  • Argatroban, 21(S): 21 (R)=35:65.

The chemical names of the two diastereoisomers mentioned above are:

• 21(S) Argatroban: (2R,4R)-1-((2S)-5-((Aminoiminomethyl)amino)-1-oxo-2-((((3S)-1,2,3,4-tetrahydro-3-methyl-8-quinolinyl)sulfonyl)amino)pentyl)-4-methyl-2-piperidine carboxylic acid (121785-72-6); and
• 21(R) Argatroban: (2R,4R)-1-((2S)-5-((Aminoiminomethyl)amino)-1-oxo-2-((((3R)-1,2,3,4-tetrahydro-3-methyl-8-quinolinyl)sulfonyl)amino)pentyl)-4-methyl-2-piperidine carboxylic acid (121785-71-5).

In 1978, S. Akamoto et al from Japanese Mitsubishi Chemical Corporation first disclosed the anti-thrombin activity of Argatroban monohydrate (U.S. Pat. No. 4,101,653). In the next 20 years, numerous researchers had in-depth studies on Argatroban about its biological activity and medicine values. In 1981, S. Akamoto compared Argatroban with heparin in vivo (Okamoto, S. et al., Biochem. Biophys. Res. Commun. 101, 440 (1981)); T. Kumoto disclosed its three-dimensional selective activity (Kumada, T. et al., Thromb. Res. 24, 285 (1981)). In 1984, R. Kumato made a clinical evaluation of hemodialysis of Argatroban (Kikumoto, R. et al., Biochemistry 23, 85 (1984)), and in 1986, he further disclosed that Argatroban can inhibit the thrombin activity of mammals, and can be used as active ingredient to treat and prevent thrombosis and as an inhibitor of platelet aggregation. Argatroban monohydrate can be used as a selective anti-thrombosis agent for treatment of chronic arterial blockage and cerebral thrombosis, etc (JP 61-48829). In 1992 and 1993, Taparelli and Jakubowski separately disclosed the reversibility of Argatroban in anti-thrombin (Taparelli, C., Trends Pharmacol. Sci., 1993, 14, 366, Jakubowski, J. A. et al, Rep. Med. Chem., 1992, 27, 99). In 1990s, many researchers such as L. R. Buch reported other related research (Buch, L. R., Cadiosvasc. Drug Rev., 1991, 9, 247, Strupcnewski, J. D. et al., Academic: San Diego, 1991; Vol. 26, p 299, Brundish, D. et al., J. Med. Chem. 1999; 42, 4584, Shebuski, R. J., Academic: San Diego, 1999; Vol. 26, p 98). In 1992, Argatroban monohydrate was first approved as an anti-thrombin medicine in Japan (Hijikata-Okunomiya, A., et al, Thromb. Hemostasis, 1992, 18, 135).

Updated in sept 2015, reader there may be duplication

	Argatroban

AC1L99H9; AC-15185; TL8005144; C04931;
MOLECULAR FORMULA:	C23H36N6O5S
MOLECULAR WEIGHT:	508.63414 g/mol

(2R,4R)-1-[5-(diaminomethylideneamino)-2-[(3-methyl-1,2,3,4-tetrahydroquinolin-8-yl)sulfonylamino]pentanoyl]-4-methylpiperidine-2-carboxylic acid, cas 74863-84-6

PATENT	SUBMITTED	GRANTED
Prodrugs of (2R)-2-Propyloctanoic Acid For the Treatment of Stroke [US7495029]	2008-06-05	2009-02-24

Tomiya Mano, Jin Shiomura, “Argatroban preparations for ophthalmic use.” U.S. Patent US5506241, issued October, 1986.

US5506241

Argatroban is an anticoagulant that is a small molecule direct thrombin inhibitor.[1] In 2000, argatroban was licensed by the Food and Drug Administration (FDA) for prophylaxis or treatment of thrombosis in patients with heparin-induced thrombocytopenia (HIT). In 2002, it was approved for use during percutaneous coronary interventions in patients who have HIT or are at risk for developing it. In 2012, it was approved by the MHRA in the UK for anticoagulation in patients with Heparin-Induced Thrombocytopenia Type II (HIT) who require parenteral antithrombotic therapy.[2]

Argatroban is given intravenously and drug plasma concentrations reach steady state in 1-3 hours.[3] Argatroban is metabolized in theliver and has a half-life of about 50 minutes. It is monitored by PTT. Because of its hepatic metabolism, it may be used in patients with renal dysfunction. (This is in contrast to lepirudin, a direct thrombin inhibitor that is primarily renally cleared).

Argatroban is a direct, selective thrombin inhibitor. The American College of Cardiologists (ACC) recommend using bivalirudin or argatroban in patients who have had, or at risk for, heparin induced thrombocytopenia (HIT) and are undergoing percutaneous coronary intervention. Argatroban is a non-heparin anticoagulant shown to both normalize platelet count in patients with HIT and prevent the formation of thrombi. Parental anticoagulants must be stopped and a baseline activated partial thromboplastin time must be obtained prior to administering argatroban.

Transitioning to warfarin in individuals with heparin induced thrombocytopenia

Argatroban is used as an anticoagulant in individuals with thrombosis and heparin induced thrombocytopenia. Often these individuals require long term anticoagulation. If warfarin is chosen as the long term anticoagulant, this poses particular challenges due to the falsely elevated prothrombin time and INR caused by argatroban. The combination of argatroban and warfarin may raise the INR to greater than 5.0 without a significant increased risk of bleeding complications.[4] One solution to this problem is to measure the chromogenic factor X level. A level < 40-45% typically indicates that the INR will be therapeutic (2-3) when the argatroban is discontinued.

http://www.google.com/patents/WO2009124906A2?cl=en

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NMR paper

Complete 1H and 13C assignments of (21R) and (21S) diastereomers of argatroban

1. Diego Colombo1,*,
2. Patrizia Ferraboschi1,
3. Paride Grisenti2 and
4. Laura Legnani3

Article first published online: 20 DEC 2007

DOI: 10.1002/mrc.2122, http://onlinelibrary.wiley.com/doi/10.1002/mrc.2122/abstract

click on image for clear view

1H NMR PREDICT

13C NMR PREDICT

References

1 Di Nisio M, Middeldorp S, Buller HR. Direct thrombin inhibitors. N Engl J Med 2005;353:1028-40. PMID 16148288

2http://www.pharmatimes.com/Article/12-07-03/UK_launch_for_Mitsubishi_s_blood_thinner_Exembol.aspx

3Dhillon S. Argatroban: A Review of its Use in the Management of Heparin-Induced Thrombocytopenia. Am J Cardiovasc Drugs 2009; 9 (4): 261-82. Link text

4. Hursting MJ, Lewis BE, Macfarlane DE. (2005). “Transitioning from argatroban to warfarin therapy in patients with heparin-induced thrombocytopenia.”. Clin Appl Thromb Hemost 11 (3): 279–87. doi:10.1177/107602960501100306. PMID 16015413.

External links

• GlaxoSmithKline’s website on argatroban

EP0823430A1 *	Aug 4, 1997	Feb 11, 1998	Mitsubishi Chemical Corporation	Method for preparing n2-arylsulfonyl-l-argininamides
US4201863 *	Aug 31, 1978	May 6, 1980	Mitsubishi Chemical Industries, Limited	N2 -Arylsulfonyl-L-argininamides and the pharmaceutically acceptable salts thereof
REFERENCE
1		None
2	*	OKAMOTO S ET AL: “Potent inhibition of thrombin by the newly synthesized arginine derivative No. 805. The importance of stereo-structure of its hydrophobic carboxamide portion” BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, ACADEMIC PRESS INC. ORLANDO, FL, US, vol. 101, no. 2, 30 July 1981 (1981-07-30), pages 440-446, XP024844713 ISSN: 0006-291X [retrieved on 1981-07-30] cited in the application
3	*	SONG H: “Method for preparing argatroban monohydrate in pure water” CASREACT,, 25 April 2007 (2007-04-25), XP002493272 & CN 1 951 937 A (TIANJIN WEIJIE TECHNOLOGY CO L [CN]) 25 April 2007 (2007-04-25)
CITING PATENT	FILING DATE	PUBLICATION DATE	APPLICANT	TITLE
WO2012136504A1	Mar 26, 2012	Oct 11, 2012	Lundbeck Pharmaceuticals Italy S.P.A.	Method for the preparation of process intermediates for the synthesis of argatroban monohydrate
CN102408468A *	Sep 20, 2011	Apr 11, 2012	海南灵康制药有限公司	Argatroban compound and preparation method thereof
EP2752412A1	Mar 26, 2012	Jul 9, 2014	Lundbeck Pharmaceuticals Italy S.p.A.	Intermediates for the synthesis of Argatroban monohydrate

Argatroban is a synthetic direct thrombin inhibitor and the chemical name is 1-[5[(aminoiminomethyl)amino]1-oxo-2-[[(1,2,3,4-tetrahydro-3-methyl-8-quinolinyl)sulfonyl]amino]pentyl]-4methyl-2-piperidinecarboxylic acid, monohydrate. Argatroban has 4 asymmetric carbons. One of the asymmetric carbons has an R configuration (stereoisomer Type I) and an S configuration (stereoisomer Type II). Argatroban consists of a mixture of R and S stereoisomers at a ratio of approximately 65:35.

The molecular formula of argatroban is C23H36N6O5S•H2O. Its molecular weight is 526.66 g/mol. The structural formula is:

Argatroban Injection is a sterile, non-pyrogenic, clear, colorless to pale yellow isotonic solution. It is supplied in a single use polyolefin bag containing 250 mg of argatroban in 250 mL sodium chloride solution (1 mg/mL). Each mL contains 1 mg argatroban, 9 mg sodium chloride, USP, and 3 mg sorbitol, NF in water for injection, USP. The pH of the solution is between 3.2 to 7.5.

ARGATROBAN

SYSTEMATIC (IUPAC) NAME
(2R,4R)-1-[(2S)-5-(diaminomethylideneamino)-2- [[(3R)-3-methyl-1,2,3,4-tetrahydroquinolin-8-yl] sulfonylamino]pentanoyl]-4-methyl-piperidine-2- carboxylic acid
CLINICAL DATA
TRADE NAMES	Argatroban
AHFS/DRUGS.COM	monograph
ROUTES OF ADMINISTRATION	intravenous
PHARMACOKINETIC DATA
BIOAVAILABILITY	100% (intravenous)
PROTEIN BINDING	54%
METABOLISM	hepatic
BIOLOGICAL HALF-LIFE	39 and 51 minutes
IDENTIFIERS
CAS REGISTRY NUMBER	74863-84-6
ATC CODE	B01AE03
PUBCHEM	CID: 440542
DRUGBANK	DB00278
CHEMSPIDER	389444
UNII	OCY3U280Y3
KEGG	C04931
CHEMBL	CHEMBL1166
CHEMICAL DATA
FORMULA	C23H36N6O5S
MOLECULAR MASS	508.635 g/mol

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