Synthesis, structure, DNA and protein binding studies, and cytotoxic activity of nickel(II) complexes containing 3,3-dialkyl/aryl-1-(2,4-dichlorobenzoyl)thiourea ligands

Abstract

A new series of nickel(II) complexes of the type [Ni(L)2] (1–6) has been synthesized by using the 3,3-dialkyl/aryl-1-(2,4-dichlorobenzoyl)thiourea ligands, and characterized by analytical and spectral (NMR, FT-IR and UV–Vis) techniques. The structures of the ligands (HL1, HL2 and HL3) and complexes (2 and 5) have been confirmed by single crystal X-ray diffraction studies. The interaction of the nickel(II) complexes (2–5) with calf thymus (CT) DNA and bovine serum albumin (BSA) protein was investigated using UV–Vis and fluorescence spectroscopic methods. Absorption and emission spectral studies indicate that complex 2 interacts with CT DNA and BSA protein more strongly than the other complexes (3, 4 and 5). Complexes 2 and 5 exhibited good cytotoxicity against A549 and HT29 cell lines at 50μM concentration.