、
(S)-3-[(S)-3-((S)-3-tert-Butoxycarbonylamino-4-methyl-2-methylene-pentanoylamino)-2-methylene-butyrylamino]-5-methyl-2-methylene-hexanoic acid 在
1-羟基苯并三唑 、
1-(3-二甲基氨基丙基)-3-乙基碳二亚胺 作用下,
以84%的产率得到methyl (3S)-5-methyl-2-methylidene-3-[[(3S)-2-methylidene-3-[[(3S)-4-methyl-2-methylidene-3-[[(3S)-5-methyl-2-methylidene-3-[[(3S)-2-methylidene-3-[[(3S)-4-methyl-2-methylidene-3-[(2-methylpropan-2-yl)oxycarbonylamino]pentanoyl]amino]butanoyl]amino]hexanoyl]amino]pentanoyl]amino]butanoyl]amino]hexanoate