Chloridobis(dimethyl­glyoximato-κ²N,N′)(ethyl pyridine-3-carboxyl­ate-κN)cobalt(III)

In the title compound, [Co(C₄H₇N₂O₂)₂Cl(C₈H₉NO₂)], which was prepared as a model complex of vitamin B₁₂, the Co^III atom, which is linked to four N atoms of the pseudo-macrocyclic (dmgH)₂ ligand (dmgH is dimethyl­glyoximate) in the equatorial plane and one Cl⁻ anion and one N atom of ethyl nicotinate in apical positions, displays an approximately octa­hedral coordination. The Co atom is 0.0187 (8) Å out of the mean plane of the four equatorial N atoms. The structure has an O...H...O bridge, which is very common in cobaloxime derivatives, with O...H distances of 1.24 (2) and 1.25 (2) Å.

Cyclo­linopeptide B methanol tris­olvate

The title compound, C₅₆H₈₃N₉O₉S·3CH₃OH, is a methanol tris­olvate of the cyclo­linopeptide cyclo(Met¹—Leu²—Ile³—Pro⁴—Pro⁵—Phe⁶—Phe⁷—Val⁸—Ile⁹) (henceforth referred to as CLP-B), which was isolated from flaxseed oil. All the amino acid residues are in an L-configuration based on the CORN rule. The cyclic nona­peptide exhibits eight trans peptide bonds and one cis peptide bond observed between the two proline residues. The conformation is stabilized by an α-turn and two consecutive β-turns each containing a 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) or the third residue (β-turns), repectively. In the crystal, the components of the structure are linked by N—H...O and O—H...O hydrogen bonds into chains parallel to the a axis.