(S)-2-[(S)-2-(2,3-Diamino-propionylamino)-3-phenyl-propionylamino]-4-methyl-pentanoic acid methyl ester 、
2-[(S)-2-Benzyloxycarbonylamino-3-(4-benzyloxy-phenyl)-propionylamino]-acetimidic acid ethyl ester; hydrochloride 以
甲醇 为溶剂,
以55%的产率得到methyl (2S)-4-methyl-2-[[(2S)-3-phenyl-2-[[2-[[[(2S)-2-(phenylmethoxycarbonylamino)-3-(4-phenylmethoxyphenyl)propanoyl]amino]methyl]-4,5-dihydro-1H-imidazole-5-carbonyl]amino]propanoyl]amino]pentanoate