Synthesis, characterization, biological approach and various applications of some novel transition metal complexes

Abstract

In the first part, new Schiff base complexes of mononuclear Mn(II), Ru(III), Co(II), Ni(II), Cu(II), and Zn(II) were synthesized by template condensation of 2,5-thiophene-dicarboxaldehyde and 2-aminobenzimidazole., and the metal complexes were structurally characterized by elemental analysis, FT-IR spectroscopy, 1H NMR spectra, electronic spectra, ESI-Ms spectra, EPR spectra, conductance measurements and magnetic susceptibility measurements. The molar conductance measurements of the complexes showed non-electrolytic nature. In all the complexes, the Schiff base coordinates through azomethine nitrogen.The physicochemical and spectroscopic measurements reveal octahedral environment for all metal complexes. The antibacterial activity, antioxidant activity and DNA interactionof the Schiff base ligand and its metal chelates were investigated to find their role in drug design. In second part, a new series of mononuclear octahedral Ru(III) complexes of general formula [RuL1-3Cl]Cl2 (1-3) where L = dianion of Schiff bases namely: 2,2'-(((1E,1'E)-thiophene-2,5-diylbis(methane-lylidene))bis-(azaneylylidene))di-phenol (H2L1), 2,2'-(((1E,1'E)-thiophene-2,5-diylbis-(methaneylyl-idene))bis(azaneylylidene))dibenzenethiol (H2L2) and 2,2'-(((1E,1'E)-thiophene-2,5-diylbis(methaneylyli-dene))bis(azaneylyli-dene))-dibenzoic acid (H2L3), respectively are synthesized and characterized by different physico-chemical techniques. The interaction of complexes with CT-DNA studied by different techniques. Further, the antiproliferative activity of the complexes on Human cervical cancer cells (HeLa) and breast cancer cells (MCF-7) were evaluated by MTT assay, which revealed that, all the complexes showed more intense inhibition against HeLa and MCF-7 cell lines.