Structure of Copper Chelate of 2-Hydroxy-4-methylthiobutanoic Acid as Trace Mineral Additive in Animal Feeding

摘要

The chelate complex of Cu2+ with 2-hydroxy-(4-methylthio)butanoate(MHA-H, the anion derived from the so-called methionine hydroxy-analogue, largely used in animal nutrition as a source of methionine, MHA) is an efficient, bioavailable trace mineral additive for animal feeding. The structure of MHA-H copper chelate was investigated by single-crystal X-ray diffraction. The crystal structure(C10H18Cu O6S2, 1, monoclinic, space group P21/c, Z = 2, a = 16.158(4), b = 4.9733(12), c = 9.159(2) ?, β = 104.786(4)°) exhibits that two MHA-H ligands coordinate with a CuII ion to form a square-planar environment completed to an octahedron through interaction with carbonyl oxygens of neighboring molecules, which expand to constitute a two-dimensional sheet coordination network. And a separation between the hydrophilic and lipophilic moieties like micelles was found in the packing structure. X-ray powder diffraction and thermogravimetric analysis were used to study the phase purity of the bulk sample and thermostability of complex 1, respectively.