5-(3,3-dimethyl-but-1-ynyl)-3-[(4-trans-methyl-cyclohexanecarbonyl)-pyrrolidin-3-(S)-yl-amino]-thiophene-2-carboxylic acid 、
3-chlorocarbonyloxy-3-methyl-azetidine-1-carboxylic acid tert-butyl ester 在
4-二甲氨基吡啶 N,N-二异丙基乙胺 作用下,
以
乙腈 为溶剂,
反应 0.25h,
以26%的产率得到3-[[2-carboxy-5-(3,3-dimethyl-but-1-ynyl)-thiophen-3-yl]-(trans-4-methyl-cyclohexanecarbonyl)-amino]-(3S)-pyrrolidine-1-carboxylic acid 1-tert-butoxycarbonyl-3-methyl-azetidin-3-yl ester