(S)-2-{(2S,3S)-2-[(S)-6-Benzyloxycarbonylamino-2-(2-nitro-phenylsulfanylamino)-hexanoylamino]-3-methyl-pentanoylamino}-propionic acid 2,5-dioxo-pyrrolidin-1-yl ester
{(2S,3S)-2-[(S)-6-Benzyloxycarbonylamino-2-(2-nitro-phenylsulfanylamino)-hexanoylamino]-3-methyl-pentanoylamino}-acetic acid 2,5-dioxo-pyrrolidin-1-yl ester
(S)-2-{(2S,3S)-2-[(S)-6-Benzyloxycarbonylamino-2-(2-nitro-phenylsulfanylamino)-hexanoylamino]-3-methyl-pentanoylamino}-propionic acid methyl ester
{(2S,3S)-2-[(S)-6-Benzyloxycarbonylamino-2-(2-nitro-phenylsulfanylamino)-hexanoylamino]-3-methyl-pentanoylamino}-acetic acid methyl ester
(S)-2-{(2S,3S)-2-[(S)-6-Benzyloxycarbonylamino-2-(2-nitro-phenylsulfanylamino)-hexanoylamino]-3-methyl-pentanoylamino}-propionic acid