Condensation of carboxylic acids 1 and 5 with unprotected α-amino acids 2 via activation by ethyl chloroformate and triethylamine proceeded effectively to afford the corresponding amides in 50–99% yields. Tripeptide 7c was obtained in 42% yield from the dipeptide 6c in a similar manner.
羧酸1和5与未保护的
α-氨基酸2在乙基
氯甲酸酯和
三乙胺的活化下高效缩合,以50-99%的产率得到相应的酰胺。类似地,从二肽6c中以42%的产率获得了三肽7c。