A novel cationic copper(II) Schiff base complex: Synthesis, characterization, crystal structure, electrochemical evaluation, anti-cancer activity, and preparation of its metal oxide nanoparticles

A tridentate ONO ligand (E)-N'-((2-hydroxynaphthalen-1-yl)methylene)acetohydrazide [HL] and its cationic Cu(II) complex [Cu(L)(H2O)]NO3 were synthesized and characterized by means of elemental analysis, FT-IR and UV-Vis spectrometry and conductivity measurements. The structure of the complex was determined using single crystal X-ray diffraction. The obtained data revealed that the Cu(II) center is coordinated by two oxygens and one nitrogen of the ligand. The fourth position is occupied by oxygen atom of a coordinated water molecule. X-ray data obtained showed that this complex possessed distorted square planar geometry around Cu(II) ion. Nitrate anion as the counter ion occupied the second sphere around the Cu(II) center via hydrogen bonding. The electrochemical behavior of the free ligand and its Cu(II) complex were studied using cyclic voltammetry. Nanoparticles (NPs) of CuO with the average size of 23 nm were prepared with thermal decomposition of the title complex and then were characterized using X-ray powder diffraction (XRD). Anti-cancer activities of the title compounds against human breast cancer (MCF-7 cells viability) were investigated and compared with each other. It was found that [Cu(L)(H2O)]NO3 complex showed higher anticancer activity than the others. (C) 2015 Elsevier B.V. All rights reserved.