反应详情

According to the procedure described in Example 1(b) for the preparation of 3(R)-t-butoxycarbonylamino-N-(2, 2-dimethyl-1(S)-(methylcarbamoyl)propyl)succinamic acid benzyl ester, 2(S)-[1-(4′-cyanobiphenyl-4-yl)-1H-pyrrol-3-yl]succinic acid 4-benzyl ester and L-t-leucine N-methylamide (see Malon, P.; Pancoska, P.; Budesinsky, M.; Hlavacek, J.; Pospisek, J.; Blaha, K. Coll. Czech. Chem Commun. 1983, 48, 2844-2861) were coupled with TBTU. Successive flash column chromatography with 0-30% EtOAc/CH2Cl2 and 2-5% MeOH/CH2Cl2 gradient eluants, respectively, and radial chromatography with 0-40% EtOAc/hex gradient eluant furnished in 66% yield 3(S)-[1-(4′-cyanobiphenyl-4-yl)-1H-pyrrol-3-yl]-N-(2,2-dimethyl-1(S)-(methylcarbamoyl)propyl)succinamic acid benzyl ester as a crisp foam.