[1–9-NαC]-Linusorb B3 (cyclo­linopeptide A) acetonitrile disolvate

The title compound, C57H85N9O9·2C2H3N [systematic name: cyclo-(prolyl-prolyl-phenyl­alanyl-phenyl­alanyl-leucyl-isoleucyl-isoleucylleucyl-val­yl) aceto­nitrile disolvate; synonym: cyclo­linopeptide aceto­nitrile disolvate], is a polypeptide with nine amino acids, viz. NαC-(Pro1–Pro2–Phe3–Phe4–Leu5–Ile6–Ile7–Leu8–Val9). It was extracted from flaxseed oil and crystallized from aceto­nitrile as a disolvate. In the title mol­ecule, there are four intra­molecular N—H⋯O hydrogen bonds. One of the two aceto­nitrile mol­ecules is hydrogen bonded to Phe3 via an N—H⋯N hydrogen bond, while the second aceto­nitrile mol­ecule is located at the other side of the peptide ring and is linked to the title mol­ecule by a C—H⋯N hydrogen bond. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, forming chains along the a-axis direction. The chains are linked by C—H⋯O hydrogen bonds, forming undulating layers parallel to the ac plane.