Synthesis, characterization of some transition-metal complexes of a new heptadentate N(5)S(2) Schiff-base ligand and the effects of these metal complexes on U2OS cells cytotoxicity and DNA cleavage activity

Abstract

Metal complexes of a heptadentate N(5)S(2) donor Schiff-base ligand were synthesized by the template reaction between 2,6-bis(2-aminothiophenoxymethyl)pyridine and 2,2 '-bipyridine-6,6'-dicarboxaldehyde in the presence of Zn(II), Cd(II), Hg(II) and Pb(II) perchlorate salts. The complexes were characterized by IR, 1H NMR, MS-FAB+, and elemental analyses. The mitochondrial activity of U2OS cells after exposure to these complexes was determined by colorimetric assay, which detects the conversion of 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) to formazon. DNA-binding activity of all complexes was also investigated using plasmid DNA pUC18 purified from E. coli.