Inhibition of DNase I Enzyme with Nickel(II) Triphenylphosphine Complexes Incorporating Tridentate Schiff Base Ligands in Vitro

The nickel(II) complexes containing 3-methoxy-salicylaldehyde - N 4 -R thiosemicarbazones (R:-H 2 ,-propyl)with triphenylphosphine coligands have been synthesized. The structure of Ni(II)-centered metal complex was approved by elemental analysis and melting point. The solid-state structure of complex 2 bearing PPh 3 as co-ligand was clarified by single crystal X-ray crystallography, which revealed square planar geometry around Ni(II) ion. T hiosemicarbazone ligands are coordinated by ONS mode to nickel(II). The potential of these complexes to inhibit the DNase I enzyme, which uses DNA as a substrate, was investigated in vitro. The results revealed that the compounds inhibited the DNase enzyme in directly and/or indirectly (by masking of DNA molecules) at ≥0.1 µg/ml concentrations in vitro .