(S)-2-[(2R,3R)-3-(4-Benzyloxy-phenyl)-2-tert-butoxycarbonylamino-3-hydroxy-propionylamino]-N-[bis-(4-methoxy-phenyl)-methyl]-succinamic acid methyl ester

(R)-((S)-2-Benzyloxycarbonylamino-3-{[bis-(4-methoxy-phenyl)-methyl]-carbamoyl}-propionylamino)-(3,5-dihydroxy-4-methoxy-phenyl)-acetic acid tert-butyl ester

[(S)-3-({[Bis-(4-methoxy-phenyl)-methyl]-carbamoyl}-methyl)-2-oxo-piperazin-1-yl]-acetic acid tert-butyl ester

(S)-N-[Bis-(4-methoxy-phenyl)-methyl]-2-[(2R,3R)-2-tert-butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionylamino]-succinamic acid methyl ester

(S)-N-[Bis-(4-methoxy-phenyl)-methyl]-2-[(2R,3R)-2-tert-butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-3-(3-chloro-4-hydroxy-phenyl)-propionylamino]-succinamic acid methyl ester