A group of combinations which have more importance in biological studies, biochemistry and also medical applications are Schiff base complexes. They have been considered by the chemists. Schiff base ligand(4, 4′-Bis-[2-(2-mercapto-phenylimino)-1-methylpropylideneamino]-biphenyl-3, 3′-diol) was provided by means of condensation of 3, 3′- dihydroxybenzidine, diacetyl and 2-aminothiophenol in absolute ethanol solvent with reflux method. Then the complexes of transition metals Cu(II), Ni(II) and VO(II) with the ligand to being determined synthesized binuclear Schiff base metal complexes and using elemental analyses, molar conductance, magnetic susceptibility, IR, UV-Vis spectral data, ESR and H1NMR studies. The elemental analysis of the complexes confine to the stoichiometry of the type [M2L]. The complexes were found to be non-electrolytic in nature on the basis of low value of molar conductance. From the spectral data an square-planar geometry for the Cu(II), Ni(II) and square pyramidal for VO(II) complexes. The possible geometries of metal complex were evaluated using 3D molecular modelling picture. The metal complexes have been screened for their antibacterial (Gram-positive bacteria like Staphylococcus aureus, Bacillus subtilis and two Gram-negative bacteria like Escherichia coli and Klebsilla pneumonia) and antifungal activity (Fusarium oxysporum and Aspergillus fumigates). DNA cleavage activities of Schiff bases and their metal complexes were monitored by agarose gel electrophoresis method in the presence of H2O2. The antioxidant activities of the complexes were also investigated through scavenging effect on DPPH.
