Synthesis and characterization of bioactive binuclear transition metal complexes of Schiff base ligand derived from 4-amino-pyrimidine-2-one, diacetyl and glycine

Abstract

A series of novel binuclear transition metal complexes was synthesized by reaction of a Schiff base ligand (1-Methyl-2-(2-oxo-1,2-dihydro-pyrimidin-4-ylimino)-propylideneamino-acetic acid) (LaH) derived from 4-amino-pyrimidine-2-one, diacetyl, glycine and corresponding chloride salt of Cu(II), Ni(II), Co(II) and Zn(II) metals in 1:1 (metal : ligand) molar ratio. The compounds were characterized by elemental analyses, molar conductance measurement, magnetic moment measurement and various spectral studies viz. IR, UV-visible, 1H-NMR, 13C-NMR, EPR and ESI-MS. Molar conductance measurement data revealed non-electrolytic nature of metal complexes. Electronic absorption spectral data, electronic paramagnetic resonance parameters and magnetic moment values revealed an octahedral geometry for binuclear metal complexes. Cyclic voltammetric study of Ni(II) complex shows a couple of one electron anodic responses near 0.70 V and 1.10 V. In vitro biological activity of Schiff base ligand and binuclear complexes has been checked against bacteria (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi) and fungi (Candida albicans and Candida parapsilosis) to assess their antibacterial and antifungal properties.