Hydrochloric Acid → HCID 178468189, compound

Participants

Reaction Steps

To a solution of tert-butyl (2S)-2-[5-(2-{(2S,4S)-4-ethoxy-1-[N-(methoxycarbonyl)-L-valyl]pyrrolidin-2-yl}-1,11-dihydroisochromeno[4′,3′:6,7]naphtho[1,2-d]imidazol-9-yl)-1H-imidazol-2-yl]pyrrolidine-1-carboxylate (0.048 g, 0.062 mmol) in a mixture of CH2Cl2 (1.0 mL) and MeOH (0.25 mL) was added HCl (in dioxanes, 4M, 0.47 mL, 1.9 mmol). The solution was stirred at room temperature for 3 h, and then concentrated to dryness under reduced pressure. To the crude intermediate suspended in CH2Cl2 (1.5 mL) was added (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (0.012 g, 0.069 mmol), HATU (0.029 g, 0.076 mmol), and DIPEA (0.050 mL, 0.28 mmol). The resulting solution was stirred at room temperature for 1.5 h. The reaction was diluted with DMF and aqueous LiOH (2.5 M, 4 drops) was added. The solution was concentrated to remove the CH2Cl2 and the crude residue was purified by preparative reverse phase HPLC (10% to 52% MeCN/water with 0.1% TFA). The desired fractions were combined and concentrated under reduced pressure to remove volatile organics. The addition of aqueous sodium bicarbonate with stirring resulted in precipitation of a white solid. The precipitate was filtered through a membrane filter and washed with water. Drying under reduced pressure afforded methyl {(2S)-1-[(2S)-2-(5-{2-[(2S,4S)-4-ethoxy-1-{(2S)-2-[(methoxycarbonyl)amino]-3-methylbutanoyl}pyrrolidin-2-yl]-1,11-dihydroisochromeno[4′,3′:6,7]naphtho[1,2-d]imidazol-9-yl}-1H-imidazol-2-yl)pyrrolidin-1-yl]-3-methyl-1-oxobutan-2-yl}carbamate (0.008 g, 17%). 1H-NMR: 400 MHz, (MeOD) δ: (Mixture of rotamers) 8.37 (s, 1H), 7.97 (s, 2H), 7.37-7.76 (m, 5H), 5.38-5.54 (m, 1H), 5.18 (s, 2H), 5.14-5.16 (m, 1H), 4.21-4.31 (m, 4H), 3.87-4.09 (m, 1H), 3.79-3.85 (m, 2H), 3.66 (s, 3H), 3.64 (s, 3H), 3.46-3.55 (m, 2H), 2.30-2.35 (m, 3H), 2.04-2.06 (m, 3H), 1.11 (m, 2H), 0.95 (d, 3H), 0.88 (d, 3H). MS (ESI) m/z 836.02 [M+H]+.

Provenance & Evidence