Antioxidant Evaluation of Co(II) and Zn(II) Complexes with Schiff base derived from 2-hydroxy-1-naphthaldehyde and p-methoxyaniline

Abstract

The Metal Complexes of Co(II) and Zn(II) with Schiff base derived from 2-hydroxy-1-naphthaldehyde and p-methoxyaniline were synthesized and characterized using elemental analysis, conductivity measurement, magnetic susceptibility, infrared spectral analysis, and solubility test. The Schiff base and its corresponding metal complexes were evaluated for antioxidant activity. The molar conductance values range (6.62-7.80Ω^-1cm²mol^-1) indicated the non-electrolytic nature of the complexes. The magnetic susceptibility values revealed that Co(II) complex is paramagnetic while Zn(II) complex is diamagnetic. The infrared spectra analysis suggested that the Schiff base behaves as a bidentate ligand. The elemental analysis results revealed slight differences between observed and calculated percentages of C, H, and N in the Schiff base and metal complexes, the metal-ligand ratio was found to be 1:2 in all the complexes. The antioxidant activity of Schiff base and its complexes was measured on the basis of the radical scavenging effect of 1,1-diphenyl-2-picryl-hydrazyl (DPPH)-free radical activity.  The results revealed that the Schiff base and its metal complexes exhibited excellent antioxidant properties.