(S)-7-[(S)-2-((S)-2-Amino-3-tert-butoxy-propionylamino)-3-tert-butoxycarbonyl-propionylamino]-7-{(1S,2R)-2-tert-butoxy-1-[(1S,2S)-1-(carboxymethyl-carbamoyl)-2-methyl-butylcarbamoyl]-propylcarbamoyl}-heptanoic acid benzyl ester 在
N,N-二异丙基乙胺 、 N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
反应 3.0h,
以50%的产率得到6-[(2S,5S,8S,14S,17S)-17-tert-Butoxycarbonylmethyl-5-((R)-1-tert-butoxy-ethyl)-14-tert-butoxymethyl-8-((S)-sec-butyl)-3,6,9,12,15,18-hexaoxo-1,4,7,10,13,16-hexaaza-cyclooctadec-2-yl]-hexanoic acid benzyl ester