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

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

4-{1-[1-(1-{[2-(1-benzyloxycarbonyl-ethylcarbamoyl)-cyclopentyl]-hydroxy-methyl}-3-methyl-butylcarbamoyl)-2-(trityl-carbamoyl)-ethylcarbamoyl]-2-methyl-propylcarbamoyl}-4-tert-butoxycarbonylamino-butyric acid benzyl ester

4-(1-benzyloxycarbonyl-2-phenyl-ethylcarbamoyl)-4-{2-[(2-{2-[2-tert-butoxycarbonylamino-3-(trityl-carbamoyl)-propionylamino]-1-hydroxy-4-methyl-pentyl}-cyclopentanecarbonyl)-amino]-propionylamino}-butyric acid benzyl ester

4-(1-benzyloxycarbonyl-2-phenyl-ethylcarbamoyl)-4-{2-[(2-{2-[2-(2-tert-butoxycarbonylamino-3-methyl-butyrylamino)-3-(trityl-carbamoyl)-propionylamino]-1-hydroxy-4-methyl-pentyl}-cyclopentanecarbonyl)-amino]-propionylamino}-butyric acid benzyl ester