Transition metal complexes of new glyoxylato-aroylhydrazones and their role in l-ascorbic acid oxidation inhibition
摘要:
We report here the synthesis of new ligands of the aroylhydrazone family. Glyoxylato-aroylhydrazones (gly-AH) with lipophilic character were designed for possible biological applications where metal chelation is desired. They were found to coordinate readily with a number of metals and the crystal structures of the copper and zinc complexes, M(py)(2)L (M = Cu, Zn): LH2 (L2) = N'-(2-hydroxy-3-(pentan-3-yl)benzylidene)-2-mesity1-2-oxoacetohydrazide have been determined. The complexes both display a distorted trigonal bipyramidal coordination geometry around the metals. Ascorbate oxidase and ascorbate peroxidase mimicking reactions were carried out to determine the ability of the title ligands to inhibit metalinduced oxidation of L-ascorbic acid via complexes generated in situ. (C) 2012 Elsevier Ltd. All rights reserved.