(R)-3-[((S)-Methylcarbamoyl-phenyl-methyl)-carbamoyl]-5-phenyl-pentanoic acid tert-butyl ester

(R)-N4-Benzyloxy-N1-((S)-methylcarbamoyl-phenyl-methyl)-2-phenethyl-succinamide

(2S,3R)-2-Hydroxy-3-[(S)-2-(4-methoxy-phenyl)-1-methylcarbamoyl-ethylcarbamoyl]-2-methyl-5-phenyl-pentanoic acid

(2R,3R)-2-Hydroxy-3-[(S)-2-(4-methoxy-phenyl)-1-methylcarbamoyl-ethylcarbamoyl]-2-methyl-5-phenyl-pentanoic acid methyl ester

(2R,4S)-2-Methyl-4-phenethyl-pentanedioic acid 1-tert-butyl ester