(S)-1-{(S)-2-[(S)-2-({(S)-1-[(S)-2-((S)-2-Amino-4-methyl-pentanoylamino)-3-phenyl-propionyl]-pyrrolidine-2-carbonyl}-amino)-4-methyl-pentanoylamino]-3-phenyl-propionyl}-pyrrolidine-2-carboxylic acid 2,5-dioxo-pyrrolidin-1-yl ester 在
吡啶 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以17.5%的产率得到(5S,8S,10aS,15S,18S,20aS)-5,15-Dibenzyl-8,18-diisobutyl-hexadecahydro-3a,6,9,13a,16,19-hexaaza-dicyclopenta[a,j]cyclooctadecene-4,7,10,14,17,20-hexaone