HCID 66594502, compound → HCID 54713647, compound

N—BOC-(2S)-2-(Hydroxymethyl)-1-pyrrolidine. To a solution of N—BOC-L-proline (4.17 g, 19.4 mmol) in THF (40 mL) at 0° C. was added BH3-THF (21.4 mL, 1 M in THF, 21.4 mmol) dropwise. The bath was removed and the resultant Solution stirred at; room temperature for 2 h. Methanol was added to quench the mixture and the solvents were removed in vacuo. The residue was taken up in ethyl acetate and washed with sodium bicarbonate and brine. The aqueous layers were extracted twice with ethyl acetate. The combined organics were dried over Na2SO4, filtered and concentrated to give N—BOC-(2S)-2-(hydroxymethyl)-1-pyrrolidine (3.82 g, 98%) as a clear oil. This material was used without further purification. 1H NMR (CDCl3) δ 3.94 (m, 1H), 3.62 (dd, J=11.2, 3.2 Hz, 1H), 3.56 (dd, J=10.8, 7.2 Hz, 1H), 3.44 (m, 1H), 3.29 (m, 1H), 2.62 (br, 1H), 1.98 (m, 1H), 1.85-1.72 (m, 2H), 1.58 (m, 1H). b) N—BOC-(2S)-2-({[(4-Methylphenyl)sulfonyl]oxy}methyl)-1-pyrrolidine. To a cold (0° C.) solution of N—BOC-(2S)-2-(hydroxymethyl)-1-pyrrolidine (350 mg, 1.74 mmol) in dichloromethane (20 mL) was added triethylamine (0.29 mL, 2.08 mmol), and toluenesulfonyl chloride (398 mg, 2.08 mmol), N,N-dimethylaminopyridine (70 mg) was added and the resultant solution was allowed to warm to rt as the bath warmed and stirred for 4 h. Water was added and the layers separated. The aqueous layer was washed with sodium bicarbonate and then with brine. The combined organics were dried over Na2SO4, filtered and concentrated followed by flash chromatography purification to give N—BOC-(2S)-2-({[(4-methylphenyl)sulfonyl]oxy}methyl)-1-pyrrolidine (460 mg, 75%) as a clear oil. 1H NMR exists as rotamers (CDCl3) δ 7.77 (d, 2H), 7.33 (m, 2H), 4.08 (m, 1H), 3.97-3.88 (m, 1H), 3.35-3.25 (m, 2H), 2.43 (s, 3H), 1.95-1.79 (m, 4H), 1.40 and 1.35 (s, 9H rotomeric BOC t-butyl). c) N—BOC-(2S-2-Cyano-1-pyrrolidine. A mixture of —N—BOC-(2S)-2-({[(4-methylphenyl)sulfonyl]oxy}methyl)-1-pyrrolidine (4.60 mg, 1.29 mmol) and KCN (256 mg, 3.88 mmol) were heated at 90° C. in DMSO (10 mid) for 6.5 h. The mixture was cooled to room temperature and EtOAc and water were added. The organics were washed with water twice and then with brine. The aqueous layers were extracted with EtOAc and the combined organics dried over Na2SO4, filtered and concentrated followed by flash chromatography purification to give N—BOC-(2S)-2-cyano-1-pyrrolidine (179 mg, 66%) as an oil. 1H NMR exists as rotomers (CDCl3) δ 3.99 (m, 1H), 3.43-3.37 (m, 2H), 2.83-2.51 (m, 2H), 2.17-1.83 (m, 4H), 1.4.6 and 1.44 (s, 9H rotomeric BOC t-butyl). d) N—BOC-(2S)-2-(2-Aminoethyl)-1-pyrrolidine. A solution of N—BOC-(2S)-2-cyano-1-pyrrolidine (179 mg, 0.85 mmol) in ethanol saturated with anhydrous ammonia was treated with Raney-Ni (1mL of 50% aq. Suspension) and 50 psi of Hz overnight. The mixture was filtered through Celite and the filtrate was concentrated in vacuo. The residue was purified by flash chromatography (10% CH3OH/CH2Cl2 with 1% NH4OH gradient elution) through a short plug of silica gel to give —N—BOC-(2S)-2-(2-aminoethyl)-1-pyrrolidine (90 mg, 50%) as a clear oil. 1H NMR exists as rotomers (CDCl3) δ 3.88-3.77 (m, 1H), 3.33-3.24 (m, 2H), 2.66 (m, 2H), 1.89-1.54 (m, 6H), 1.40 (s, 9H), e) {2-[(2S)-2-Pyrrolidinyl]ethyl}amine. A solution of —N—BOC-(2S)-2-(2-aminoethyl)-1-pyrrolidine (90 mg, 0.42 mmol) in THF (6 mL) was treated with 4 N HCl (aq) (2 mL) and stirred at room temperature for 3 h. The mixture was concentrated in vacuo to give the title compound as its HCl salt. A portion of this material (40 mg) was dissolved in methanol and treated with solid supported carbonate resin (MP-Carbonate, Argonaut Technologies) to freebase the amines. After 30 minutes, the solution was filtered through a fritted tube and the solvents removed carefully in vacuo to give {2-[(2S)-2-pyrrolidinyl]ethyl}amine (30 mg) as its free base. 1H NMR (CDCl3) δ 3.06 (m, 1H), 2.94 (m, 1 TI), 2.83 (m, 1H), 2.79-2.69 (m, 2H), 1.90-1.56 (m, 6H). f) (3aS,13aS)—N-[(2,4-Difluorophenyl)methyl]-7,9-dioxo-8-[(phenylmethyl)oxy]-1-1,2,3,3a,4,5,7,9,13,13a-decahydropyrido[1′,2′:4,5]pyrazino[1,2-a]pyrrolo[1,2-d]pyrimidine-10-carboxamide. A solution of 16a (30 mg, 0.06 mmol), {2-[(2S)-2-pyrrolidinyl]ethyl}amine (30 mg, 0.26 mmol) and 2 drops of glacial acetic acid were heated under microwave conditions at 140° C. for 10 min. Upon cooling, Celite was added to the mixture and the solvents removed in vacuo and the material was purified via silica gel chromatography (2% CH3OH/CH2Cl2 gradient elution) to give (3aS,13aS)—N-[(2,4-Difluorophenyl)methyl]-7,9-dioxo-S-[(phenylmethyl)oxy]-1,2,3,3a,4,5,7,9,13,13a-decahydropyrido[1′,2′:4,5]pyrazino[1,2-a]pyrrolo[1,2-d]pyrimidine 10-carboxamide. (25 mg, 74%) as a film. 1H NMR (CDCl3) δ 10.44 (m, 1H), 8.32 (s, 1H), 7.59 (m, 2H), 7.38-7.24 (m, 4H), 6.80 (m, 2H), 5.28-5.22 (m, 2H), 4.67 (dd, J=13.6, 2.8 Hz, 1H), 4.62 (m, 2H), 4.26 (m, 1H), 4.11-4.03 (m, 2H), 2.91 (m, 1H), 2.81 (m, 1H), 2.37 (m, 1H), 2.24 (m, 1H), 1.92 (m, 1H), 1.82-1.76 (m, 3H), 1.52-1.38 (m, 2H); ES+ MS: 535 (M+1). g) (3aS,13aS)—N-[(2,4-Difluorophenyl)methyl]-8-hydroxy-7,9-dioxo-1,2,3,3a,4,5,7,9,13,13a-decahydropyrido[1′,2′:4,5]pyrazino[1,2-a]pyrrolo[1,2-d]pyrimidine-10-carboxamide. To a solution of (3aS,13aS)—N-[(2,4-difluorophenyl)methyl]-7,9-dioxo-8-[(phenylmethyl)oxy]-1,2,3,3a,4,5,7,9,13,13a-decahydropyrido[1′,2′:4,5]pyrazino[1,2-a]pyrrolo[1,2-c]pyrimidine-10-carboxamide (25 mg, 0.05 mmol) in methanol (8 mL) was added 10% Pd/C (10 mg). Hydrogen was bubbled through the reaction mixture via a balloon for 18 h. The resultant mixture was filtered through Celite with methanol and dichloromethane. The filtrate was concentrated in vacuo to give the title compound (14 mg, 67%) as a white solid. NMR (CDCl3) δ 12.53 (br, 1H), 10.44 (s, 1H), 8.29 (s, 1H), 7.34 (m, 1H), 6.78 (m, 2H), 4.71-4.58 (m, 3H), 4.29-4.14 (m, 3H), 2.99 (m, 1H), 2.88 (m, 1H), 2.44 (m, 1H), 2.30 (m, 1H), 1.97-1.38 (m, 6H); ES+ MS: 445 (M+1).

1. customHydrogen was bubbled through the reaction mixture via a balloon for 18 h
2. filtrationThe resultant mixture was filtered through Celite with methanol and dichloromethane
3. concentrationThe filtrate was concentrated in vacuo

ORD record

ord-fbe184f1e95740a2bc5c257b31cabb92

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08778943B2