Hydrochloric Acid → HCID 67681969, compound

Participants

Reaction Steps

A solution of (S)-benzyl 2-(5-(7-(2-((S)-1-(tert-butoxycarbonyl)pyrrolidin-2-yl)-1H-benzo[d]imidazol-6-yl)dibenzo[b,d]thiophen-3-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate (0.75 g, 1.0 mmol), concentrated HCl (2.0 mL) and ethanol (12 mL) was heated to 60° C. for one hour. The reaction was concentrated and redissolved in a minimal amount of methanol. An equal volume of dichloromethane was added and the solution was again concentrated. Dichloromethane was added to the resulting residue and concentrated off three more times, until the crude material was a powder. A portion of the crude amine (0.29 g, ˜0.40 mmol) was dissolved in dimethylformamide (3.9 mL). To this solution was added (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (82 mg, 0.47 mmol), HATU (163 mg, 0.43 mmol) and diisopropylethylamine (0.70 mL, 4.0 mmol). The reaction was stirred at room temperature for one hour, and then diluted with acetonitrile (2 mL) and methanol (2 mL). To this solution was added ten drops of 5M aqueous NaOH solution and stirring was continued for 30 minutes. The reaction was diluted with ethyl acetate and the organic layer was washed with water and brine. The combined aqueous washings were extracted three times with ethyl acetate, and the combined organic layers were dried (MgSO4) and concentrated. The crude material was purified by flash column chromatography to yield (S)-benzyl 2-(5-(7-(2-((S)-1-((S)-2-(methoxycarbonylamino)-3-methylbutanoyl)pyrrolidin-2-yl)-1H-benzo[d]imidazol-6-yl)-dibenzo[b,d]thiophen-3-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate (0.19 g, ˜60%). LCMS-ESI+: calculated for C45H45N7O5S: 795.95; observed [M+1]+: 796.73.

Provenance & Evidence