Synthesis, crystal structure and pharmacological evaluation of two new Cu(II) complexes of 2-oxo-1,2-dihydroquinoline-3-carbaldehyde (benzoyl) hydrazone: A comparative investigation

Two new copper(II) complexes have been synthesized by reacting 2-oxo-1,2-dihydroquinoline-3-carbaldehyde (benzoyl) hydrazone (H2L) with CuCl2·2H2O or Cu(NO3)2·3H2O. The structures of the complexes have been determined by single crystal X-ray diffraction studies. Results obtained using spectroscopic methods strongly suggested that the ligand and its Cu(II) complexes could interact with calf thymus DNA through intercalation. In the case of protein binding, the obtained results indicated that all the three compounds could quench the intrinsic fluorescence of bovine serum albumin through static quenching process. In addition, antioxidant activity tests showed that H2L and its copper(II) complexes possess significant scavenging effect against free radicals. Further, the two copper(II) complexes exhibited effective cytotoxic activity against a panel of human cancer cell lines.

2-oxo-1,2-dihydroquinoline-3-carbaldehyde(benzoyl)hydrazone and its copper(II) complexes have been synthesized. Their structure activity relationships on DNA and protein binding, antioxidative and cytotoxic activity have been investigated.Figure optionsDownload as PowerPoint slideHighlights
► Ligand coordinated through ONO in both the Cu(II) complexes.
► Bind to CT-DNA via intercalation and to BSA in tyrosine and tryptophan residues.
► Possess significant radical scavenging properties.
► Appreciable cytotoxic activity against cancer cell lines.