Physicochemical characterization of Cu(II) complexes with SOD-like activity, theoretical studies and biological assays

The mononuclear Cu(II)) complex, [Cu(o-Va)(2)(H2O)(2)] (o-HVa = o-vanillin, 2-hydroxy-3-methoxybenzaldehyde) has been synthesized and characterized by elemental analyses. FTIR, FT-Raman, and electronic spectroscopies and compared with the results obtained for the free ligand The optimized geometry, the harmonic vibrational frequencies and the electronic transitions of the complex and the ligand were Calculated Using methods based on the density functional theory. Antimicrobial activity against Escherichia call and Staphylococcus aureus and SOD-mimic activities of the complex were studied and compared with the analogous copper complex with vanillin, [Cu(Va)(2)(H2O)(2)] Stability of the compounds in the essayed solution and with time was determined by means of conductimetric measurements Their redox behavior was Studied by cyclic voltammetry and was compared with that observed for the ligands. The complexes undergo two main reductions and one oxidation processes involving the metal center and the coordinated ligand, respectively. (C) 2009 Elsevier Ltd. All rights reserved.