1-Hydroxybenzotriazole → HCID 68802882, compound

Participants

Reaction Steps

A solution of 520 mg (0.56 mmol) of N-[N-[N-[O-tert-butyl-N-[(9-fluorenyl)methoxycarbonyl]-L-a-glutamyl]-2-methyl-L-phenylalanyl]-3-methyl-L-valyl]-3-cyclopentyl-L-alanine benzyl ester in 3 ml of piperidine and 12 ml of dichloromethane was stirred at room temperature for 30 minutes. The solvent was removed by evaporation and the residue was chromatographed on silica gel using firstly ethyl acetate/petrol (1:1) and then methanol/dichloromethane (1:9) for the elution. The resulting amine was added to a solution of 207 mg (0.504 mmol) of N-(9-fluorenyl-methoxycarbonyl)-O-tert-butyl-L-α-aspartic acid, 78 mg (0.51 mmol) of 1-hydroxybenzotriazole and 134 mg (0.7 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride in 10 ml of dichloromethane and stirred at room temperature for 18 hours. The solution was then extracted with 2M hydrochloric acid and saturated sodium bicarbonate solution and dried over anhydrous magnesium sulphate. Evaporation, trituration with diethyl ether and filtration gave 440 mg of N-[N-[N-[N-O-tert-butyl-N-[(9-fluorenyl)methoxycarbonyl]-L-a-aspartyl]-O-tert-butyl-L-α-glutamyl]-2-methyl-L-phenylalanyl]-3-methyl-L-valyl]-3-cyclopentyl-L-alanine benzyl ester as a white solid; MS: m/e 1101 [M+H].

Provenance & Evidence