(S)-2-({(1R,2R)-2-[(1S,2S)-2-((S)-2-tert-Butoxycarbonylamino-4-methylsulfanyl-butyrylamino)-1-hydroxy-4-methyl-pentyl]-cyclopentanecarbonyl}-amino)-3-methyl-butyric acid benzyl ester

(S)-2-[((1R,2R)-2-{(1S,2S)-2-[(S)-2-((S)-2-Acetylamino-4-methyl-pentanoylamino)-4-methylsulfanyl-butyrylamino]-1-hydroxy-4-methyl-pentyl}-cyclopentanecarbonyl)-amino]-propionic acid 2,2,2-trichloro-ethyl ester

(S)-2-[((1R,2R)-2-{(1S,2S)-2-[(S)-2-((S)-2-Acetylamino-4-methyl-pentanoylamino)-4-methylsulfanyl-butyrylamino]-1-hydroxy-4-methyl-pentyl}-cyclopentanecarbonyl)-amino]-3-methyl-butyric acid benzyl ester

(S)-2-((S)-2-{[(1R,2R)-2-((4S,5S)-3-tert-Butoxycarbonyl-4-isobutyl-2,2-dimethyl-oxazolidin-5-yl)-cyclopentanecarbonyl]-amino}-propionylamino)-pentanedioic acid dibenzyl ester

(S)-2-[((1R,2R)-2-{(1S,2S)-2-[(S)-2-tert-Butoxycarbonylamino-3-(trityl-carbamoyl)-propionylamino]-1-hydroxy-4-methyl-pentyl}-cyclopentanecarbonyl)-amino]-propionic acid benzyl ester