(S)-5-(benzyloxy)-2-(N-(2-((tert-butoxycarbonyl)amino)ethyl)-2-(5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)acetamido)-5-oxopentanoic acid 在
benzotriazol-1-yloxyl-tris-(pyrrolidino)-phosphonium hexafluorophosphate 、
氯化铵 、
N,N-二异丙基乙胺 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
反应 2.0h,
以71%的产率得到benzyl (S)-5-amino-4-{N-[2-((tert-butoxy)carbonylamino)ethyl]-2-[5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl]-1-oxoethylamino}-5-oxopentanoate