(2S)-1-(2-(((benzyloxy)carbonyl)amino)-3-phenylpropanoyl)pyrrolidine-2-carboxylic (isobutyl carbonic) anhydride

(2S,3S)-2-{[(S)-1-((S)-2-Benzyloxycarbonylamino-3-phenyl-propionyl)-pyrrolidine-2-carbonyl]-amino}-3-hydroxy-butyric acid methyl ester

(2S,3R)-2-{[(S)-1-((S)-2-Benzyloxycarbonylamino-3-phenyl-propionyl)-pyrrolidine-2-carbonyl]-amino}-3-hydroxy-butyric acid methyl ester

(2-methylpropoxy)carbonyl N-[(benzyloxy)carbonyl]-D-valinate

(2S,3S)-2-{[(S)-1-((S)-2-Amino-3-phenyl-propionyl)-pyrrolidine-2-carbonyl]-amino}-3-hydroxy-butyric acid methyl ester