(2S)-2-tert-butoxycarbonylamino-5-(tert-butyldimethyl-silanyloxy)-pentanoic acid 、
(1R,3S)-methyl 8-benzyloxy-1-((benzyloxy)methyl)-1,2,3,4-tetrahydro-5,7-dimethoxy-6-methylisoquinoline-3-carboxylate 在
N-羟基-7-氮杂苯并三氮唑 、
N,N-二异丙基乙胺 、 Methanaminium,N-[(dimethylamino)(3H-1,2,3-triazolo[4,5-b]pyridin-3-yloxy)methylene]-N-methyl-, hexafluorophosphate(1-) 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以84%的产率得到methyl (1R,3S)-2-[(2S)-5-[tert-butyl(dimethyl)silyl]oxy-2-[(2-methylpropan-2-yl)oxycarbonylamino]pentanoyl]-5,7-dimethoxy-6-methyl-8-phenylmethoxy-1-(phenylmethoxymethyl)-3,4-dihydro-1H-isoquinoline-3-carboxylate