A binuclear chloride bridged copper(II) complex with a modified ligand structure and different coordination environment and mononuclear cobalt(II) complexes with a pyridylpyrazole ligand: Synthesis, structure and cytotoxic activity

Abstract

One new binuclear chloride bridged copper(II) complex [L′(Cl)Cu-(μ-Cl)-Cu(pz)L′](PF6)2 (1) and two mononuclear cobalt(II) complexes [Co(Cl)L]BF4·1/2CH3OH (2) and [Co(Cl)L]PF6 (3) where L={N,N-bis(3,5-dimethylpyrazol-1-ylmethyl)}(2-aminomethyl)pyridine, L′={N-(3,5-dimethylpyrazol-1-ylmethyl)}(2-aminomethyl)pyridine and pz=3,5-dimethyl-pyrazole have been synthesized and characterized by physico-chemical methods and single crystal X-ray diffraction studies. The crystal structure of the binuclear copper(II) complex [L′(Cl)Cu-(μ-Cl)-Cu(pz)L′](PF6)2 shows that the two square plane copper(II) moieties are joined through a single chloride (μ-Cl) bridge and the coordination environment around the two copper atoms are different, whereas the cobalt ion in [Co(Cl)L]BF4·1/2CH3OH has a trigonal bipyramidal geometry. The cytotoxic activity of the ligand, and the copper and cobalt complexes 1 and 2 were measured in vitro against the human lymphocyte HL-60 and it shows that the metal complexes have different cytotoxic activities to the organic ligand.