Synthesis of Nickel(II) Complexes Based on Dialkylphosphorylpyridines and Their Cytotoxic Activity

Abstract

Bis-chelate nickel complex of composition [L2Ni(H2O)2](BF4)2 (4), where L = 1,3-dibenzhydryl-5-(pyridin-2-yl)-5-oxo-1,3,5-diazaphosphorinane, and tris-chelate complexes 5 and 6 of composition [L3Ni](BF4)2, where L = 2-diethylphosphorylpyridine and 2-diisopropylphosphorylpyridine, based on 1,4-N,O ligands L2–L4 with phosphoryl groups of acyclic and cyclic structure have been prepared. The structure and composition of complexes 4–6 were confirmed by mass-spectrometry, IR spectroscopy, thermogravimetric and elemental analysis. The structure of complexes 4-EtOH and 5 in crystals has been established by X-ray diffraction study. Cytotoxic properties toward M-HeLa and HuTu80 cancer cells and Chang Liver normal cell lines for the previously prepared nickel(II) complexes 1–3 based on 2-(oxophospholane)pyridines and the nickel(II) complexes obtained in this work have been studied. It has been found that the complexes with ligands containing cyclic phosphoryl groups show higher cytotoxicity toward cancer cells as compared with the complexes with their acyclic analogs.