Synthesis, Spectral Characterization and Biological Evaluation of Cu(II) Complexes with Schiff Bases Derived from 2-Aminobenzoic Acid

Abstract

INTRODUCTIONSchiff bases are the versatile ligands which are synthesized by the condensation of an amino compound with carbonyl compounds. These compounds and their metal complexes are very important as catalysts in various biological systems, polymers, dyes, medicinal and pharmaceutical fields [1,2]. Schiff bases have been widely explored for industrial applications. These have been used as corrosion inhibitor [3], in electrochemical sensors [4], in non-linear optical devices [5] and as an electroluminescent material [6], etc., Especially, Schiff bases with nitrogen and oxygen donor atoms play important role in biological systems and represent interesting models for metalloenzymes, which efficiently catalyze the reduction of dinitrogen and dioxygen [7].In this study, we have synthesized ligands 2-[(2-hydroxy-3-methoxybenzylidene)amino]benzoic acid (L 1 ) from o-vanillin and 2-aminobenzoic acid and 2-[(2-hydroxybenzylidene)-amino]benzoic acid (L 2 ) from salicylaldehyde and 2-amino benzoic acid. Copper(II) complexes of these ligands were synthesized and characterized by colorimetry, thin-layer chromatography, IR, 1 H NMR, UV, molar conductance and magnetic susceptibility measurements. The in vitro antimicrobial activity of the free Schiff bases and its Cu(II) complexes were also investigated. EXPERIMENTALThe reagents such as o-vanillin, salicylaldehyde, 2-aminobenzoic acid, copper(II)chloride dihydrate and the solvents