(S)-2-Amino-3-[(S)-2-amino-3-((S)-2-amino-3-tert-butoxycarbonylamino-propionylamino)-propionylamino]-propionic acid methyl ester; compound with acetic acid

(S)-2-(2,3-Bis-benzyloxy-benzoylamino)-3-{(S)-2-(2,3-bis-benzyloxy-benzoylamino)-3-[(S)-2-(2,3-bis-benzyloxy-benzoylamino)-3-tert-butoxycarbonylamino-propionylamino]-propionylamino}-propionic acid methyl ester