4-氰基苯乙酸 、 H-beta-Ala-Asp(O-tBu)-Phe-O-tBu 以yielding 250 mg of N-[N-[N-(p-cyanophenylacetyl)-β-alanyl]-3-t-butoxycarbonyl-L-alanyl]-3-phenyl-L-alanine t-butyl ester, m.p. 93°-94° C.的产率得到N-[N-[N-(p-cyanophenylacetyl)-β-alanyl]-3-t-butoxycarbonyl-L-alanyl]-3-phenyl-L-alanine t-butyl ester