Abstract:

The interactions of Fe3+, Cr3+, Cu2+ with propyl gallate(PG) in water were studied. The solid complexes of PG-Fe, PG-Cr, PG-Cu were characterized by UV-Vis, 1H NMR, IR, MS, elemental analysis, molar conductance and cyclic voltammetry. The results support the formation of the complexes with the formulae [C10H10O5]2Fe·H2O, [C10H10O5]3Cr·2H2O and [C10H10O5]2Cu·2H2O for investigated metal cations. The IR spectra show that the phenol hydroxyl group was coordinated to the metal center to form the Ph—O—M bond. The electrochemical data suggest that the metal complexes were more effective antioxidants than PG ligand, and the antioxidative property follows the order:PG-Cu＞PG-Cr＞PG-Fe. The superoxide dismutase(SOD) like activity of the metal complexes was measured by means of a reduction of NBT by VB2. The results indicate that the three metal complexes could catalyze the disproportionation of the superoxide anion free radical (O-2·), and could be used as the active center model complexes of SOD.

Key words: propyl gallate,complex,cyclic voltammetry,SOD