Cyclo-linopeptide K butanol disolvate monohydrate

Acta Crystallogr Sect E Struct Rep Online. 2011 Sep 1;67(Pt 9):o2360-1. doi: 10.1107/S1600536811032363. Epub 2011 Aug 17.

Abstract

The title compound, C(56)H(83)N(9)O(11)S·2C(4)H(10)O·H(2)O, is a butanol-water solvate of the cyclo-linopeptide cyclo(Metsulfone(1)-Leu(2)-Ile(3)-Pro(4)-Pro(5)-Phe(6)-Phe(7)-Val(8)-Ile(9)) (henceforth referred to as CLP-K) which was isolated from flax oil. All the amino acid residues are in an l configuration based on the CORN rule. The cyclic nona-peptide exhibits eight trans peptide bonds and one cis peptide bond observed between the two proline residues. The conformation is stabilized by an α- and a β-turn, each containing an N-H⋯O hydrogen bond between the carbonyl group O atom of the first residue and the amide group H atom of the fourth (α-turn) and the third residue (β-turn), repectively. In the crystal, the components of the structure are linked by inter-molecular N-H⋯O and O-H⋯O hydrogen bonds into a two-dimensional network parallel to (001). The -C(H(2))OH group of one of the butanol solvent mol-ecules is disordered over two sets of sites with refined occupancies of 0.863 (4) and 0.137 (4).