Synthesis and Antimicrobial Efficacies of Bidentate Schiff Metal Complexes Derived From Terephthalaldehyde and 2-Aminophenol

Abstract

The objective of this paper was to investigate the synthesis and antimicrobial efficacies of Bidentate Schiff metal complexes of Mn (II), Co (II), Ni (II), Cu (II) and Zn (II) complexes derived from equimolar ratio of terephthalaldehyde (TPA) and 2-aminophenol (AMP) The ligand and complexes were characterized using physicochemical techniques - melting point, solubility, conductivity and spectroscopic parameters - FTIR and UV-Visible. FTIR spectrum of the Schiff base ligand showed absorption bands at 1671 cm^-1 which shifted to 1689 - 1698 cm^-1 in the spectra of metal complexes indicating of coordination of metal ion to the ligand through azomethine N-atom. In the same vein, the sharp absorption bands at 3323 - 3366 cm^-1 in the spectra of metal complexes showed coordinated water of crystallization. Square planar geometry was proposed for all metal complexes based on the available spectroscopic data obtained. The antimicrobial results showed that both the ligands and the metal complexes inhibited bacterial and fungi growth, more effective than some of the standard antimicrobial drugs used. The Cu (II) complex exhibited encouraging antibacterial activities against all strains of microbes, the ligand, Mn (II), and Co (II) metal complexes were only active against staphylococcus aureus, Escherichia Coli, and Candida albicans while Ni (II) complex showed no activity against both bacteria and fungi strains. MIC (Mininum Inhibitory Concentration) of Manganese complex is 20 mg/ml while MIC that prevents the visible growth of the tested organisms for Schiff base ligand, Copper and Cobalt complexes is 40 mg/ml.