Copper(II) Compounds of 4-Nitrobenzohydrazide with Different Anions (ClO4 - , NO3 - and Br- ): Synthesis, Characterization, DFT Calculations, DNA Interactions and Cytotoxic Properties.

Copper complexes containing 4-nitrobenzohydrazide (4-NH), [Cu(4-NH)2 (ClO4 )2 ] (1), [Cu(4-NH)2 (NO3 )2 ] (2) and [Cu(4-NH)2 Br2 ] (3), were synthesized and characterized by various spectroscopy. DFT calculations have revealed a distorted octahedral for 1, 2 and 3. DNA interactions of 1-3 toward calf-thymus DNA were investigated by absorption titration, viscosity, fluorescence spectroscopy and gel electrophoresis. All complexes bind to DNA via intercalation mode. The Kb values have shown the binding ability in the order of 3>2>1. The in vitro cytotoxicity of 1-3 was tested against two human cancer cells (HeLa and MCF-7) and normal Vero cells by MTT assay. All complexes show anticancer ability upon increasing time, but the ligand is inactive. Complex 3 with the Br- anion gives the lowest IC50 values of 19.26±2.43 μg/mL toward MCF-7. Moreover, all complexes were not arrested at any cell cycle phases. However, the sub-G1 populations were enhanced upon increasing the complex concentration. Therefore, they may induce apoptotic cell death for both cancer cells. The antibacterial activity of 1-3 was tested against E. coli, Salmonella and Campylobacter. Complex 3 gives the best activity toward Campylobacter (0.156×103  μg/mL).