Hydrogen chloride-ethyl acetate → HCID 68413883, compound

Participants

Reaction Steps

To a mixture of tert-butyl (1R,2S)-2-({N5-[(benzyloxy)carbonyl]-N2-[(1-methyl-1H-indol-2-yl)carbonyl]-L-ornithyl}amino)cyclopentanecarboxylate (0.40 g) and chloroform (10 ml) was added a 4 M hydrogen chloride/ethyl acetate solution (20 ml) under ice-cooling, followed by stirring at room temperature for 3 hours. The reaction mixture was concentrated under reduced pressure, and to the residue were added ethyl acetate and water. The aqueous layer was separated, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The organic layer was concentrated under reduced pressure, and diethyl ether was added to the residue for solidification, followed by washing with diethyl ether and a 50% aqueous methanol solution. Further, it was purified by silica gel column chromatography (0→2% MeOH/chloroform), and the obtained solid was washed with a 50% aqueous methanol solution to obtain (1R,2S)-2-({N5-[(benzyloxy)carbonyl]-N2-[(1-methyl-1H-indol-2-yl)carbonyl]-L-ornithyl}amino)cyclopentanecarboxylic acid (0.25 g).

Provenance & Evidence