SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY OF MIXED LIGAND COMPLEXES OF INNER TRANSITION METAL WITH L-ASCORBIC ACID, ITS DERIVATIVE AND ADENINE BASE

Abstract

Complexes of La(III), Ce(III), Nd(III) and Gd(III) with mixed Ligand of 2-aminopurene and L-ascorbic acid derivative were prepared in aqueous ethanol. The two types of mixed ligand complexes [M(AA)(ADE)(H2O)2]+and [M(IPAA) (ADE)(H2O)2]+ have been synthesized. All complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, IR, UV-VISSIBLE, NMR, ESR and Mass spectral studies. IR spectra of the complexes reveal that the complex formation occurred through both nitrogen and oxygen atoms. On the basis of electronic spectral data and magnetic susceptibility measurement octahedral geometry has been proposed for the complexes. The ESR spectral data of the M (III) complexes showed that the metal-ligand bonds have considerable covalent character. The electrochemical behaviour of mixed Ligand M(III) complexes was studied which showed that complexes of IPAA appear at more positive potential as compared to those for corresponding AA complexes. In addition, biological activity of the synthesised metal complexes against Salmonella typhi, Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae bacteria and Aspergillus niger, Aspergillus flavus, Fusarium oxisporium and Trichoderma viride fungi respectively were examined in-vitro. Some of the metal complex displayed pounced biological activity.