SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY OF MANGANESE(II) AND NICKEL(II) COMPLEXES OF 7-DIETHYLAMINOBENZYL-8-HYDROXYQUINOLINE

Abstract

8-Hydroxyquninoline Mannich base namely 7-diethylaminobenzyl-8-hydroxyqunioline(DEBQ) was synthesized and characterized by elemental analysis and spectral studies. Chelates of DEBQ with manganese(II) and nickel(II) were isolated and structurally  characterized by elemental analysis, electrical conductance, magnetic susceptibility measurement, thermal analysis, IR,UV-Vis, EPR and Mass spectral data. The Mannich base ligand is bidentate and chelates through the phenolic oxygen and the aliphatic tertiary amino nitrogen atoms. Based on the magnetic and electronic spectral data all the Mn^II complexes are assigned an octahedral geometry and Ni^II complexes are assigned a tetrahedral geometry. Antimicrobial susceptibility screening of the Mannich base shows that it possesses excellent activity when compared to the standard drugs and the metal complexes studied. Among the chelates, Mn^II chelate is more potent than Ni^II  chelate. Thermal analysis of a few compounds shows two stage decomposition patterns.