(2R,3R,4S)-4-amino-3-hydroxy-2-[(naphthalen-1-ylmethyl)-amino]-5-phenyl-pentanoic acid [(S)-1-(2-hydroxy-4-methoxy-benzylcarbamoyl)-2-methyl-propyl]-amide 、
Cbz-L-叔亮氨酸 、 O-(1,2-dihydro-2-oxo-1-pyridyl)-N,N,N',N'-tetramethyluronium tetrafluoroborate 在
N,N-二异丙基乙胺 作用下,
以
N,N-二甲基乙酰胺 、
乙酸乙酯 为溶剂,
生成
((S)-1-{(1S,2R,3R)-1-Benzyl-2-hydroxy-3-[(S)-1-(2-hydroxy-4-methoxy-benzylcarbamoyl)-2-methyl-propylcarbamoyl]-3-[(naphthalen-1-ylmethyl)-amino]-propylcarbamoyl}-2.2-dimethyl-propyl)-carbamic Acid Benzyl Ester