Synthesis, spectral characterization and biological evaluation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes with thiosemicarbazone ending by pyrazole and pyridyl rings

Here we present the synthesis of the new Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes with chelating ligand (Z)-(2-((1,3-diphenyl-1H-pyrazol-4-yl)methylene) hydrazinyl)(pyridin-2-ylamino) methanethiol. All the complexes were characterized by elemental analysis, IR, H-1 NMR, UV-vis, magnetic susceptibility measurements and EPR spectral studies. IR spectra of complexes showed that the ligand behaves as NN neutral bidentate, NSN mononegative tridentate and NSNN mononegative tetradentate. The electronic spectra and the magnetic measurements suggested the octahedral geometry for all complexes as well as the EPR confirmed the tetragonal distorted octahedral for Cu(II) complex. Cd(II) complex showed the highest inhibitory antioxidant activity either using ABTS method. The SOD-like activity exhibited those Cd(II) and Zn(II) complexes have strong antioxidative properties. We tested the synthesized compounds for antitumor activity and showed that the ability to kill liver (HePG2) and breast (MCF-7) cancer cells definitely. (C) 2014 Elsevier B.V. All rights reserved.