Synthesis, characterization and crystal structures of copper(II) and nickel(II) complexes of propargyl arm containing N2O2 ligands: Antimicrobial activity and DNA binding

Ni(II) and Cu(II) complexes of propargyl arm containing N2O2 Schiff base donor ligands (L1–L3) were prepared and characterised by elemental analysis, IR, NMR and UV–Vis spectroscopy. The crystal structures of CuL3 and NiL3 were determined by single crystal X-ray diffraction measurements. The coordination geometry around the copper and nickel centres is square planar, with the plane formed by the N2O2 donors of the Schiff base ligand. The crystal packing is stabilized by C–H⋯O intermolecular hydrogen bonding and further influenced by C–H⋯π interactions. The electrochemical behaviour of the synthesized copper complexes was studied and the results obtained evidenced their irreversible oxidation. Antibacterial activity was assayed against selective Gram(+ve) and Gram(−ve) microorganisms. The DNA binding behaviour of the complexes was investigated using absorption and fluorescence titration measurements.

Propargyl arm containing N2O2 Schiff bases and their copper and nickel complexes were synthesized. Single crystal X-ray analysis identified a square planar geometry for the complexes. Their DNA binding abilities and bacterial activities were discussed.Figure optionsDownload as PowerPoint slide