tert-butyl (R)-(3,5-dihydroxy-4-methoxyphenyl)glycine

(R)-((S)-2-Benzyloxycarbonylamino-3-cyano-propionylamino)-(3,5-dihydroxy-4-methoxy-phenyl)-acetic acid tert-butyl ester

(R)-[3,5-Bis-(tert-butyl-dimethyl-silanyloxy)-4-methoxy-phenyl]-{(S)-2-[(2R,3R)-2-tert-butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-fluoro-3-nitro-phenyl)-propionylamino]-3-cyano-propionylamino}-acetic acid tert-butyl ester

(R)-((S)-2-tert-Butoxycarbonylamino-3-cyano-propionylamino)-(3,5-dihydroxy-4-methoxy-phenyl)-acetic acid tert-butyl ester

(S)-2-[(2R,3R)-2-tert-Butoxycarbonylamino-3-(4-fluoro-3-nitro-phenyl)-3-hydroxy-propionylamino]-3-cyano-propionic acid methyl ester