(S)-4-Methyl-2-[(4-phenyl-piperazine-1-carbonyl)-amino]-pentanoic acid 、
(S)-tert-butyl 4-benzyloxyphenylalaninate 在
silica gel 、 ethyl acetate heptane 作用下,
以to give the title compound as a white crystals (0.84 g, 46%), mp=67-69° C.的产率得到[S-(R*,R*)]-3-(4-Benzyloxy-phenyl)-2-{4-methyl-2-[(4-phenyl-piperazine-1-carbonyl)-amino]-pentanoylamino}-propionic acid tert-butyl ester