Synthesis and Structure of Cytotoxic Copper(II) Complexes Based on di(o-tolyl)Phosphinic Acid and 2,2'-Bipyridine/1,10-Phenanthroline.

The following series of copper(II) complexes based on di(o-tolyl)phosphinic acid (HL) and 1,10-phenanthroline (phen), 5-chloro-1,10-phenanthroline (Cl-phen), 4,7-dimethyl-1,10-phenanthroline (dmphen), 2,2′-bipyridine (bipy) is prepared and characterized: [Cu(OH)L]n (1), [Cu(phen)(H2O)L2] (2), [Cu(dmphen)(H2O)L2] (3), [Cu(Cl-phen)(H2O)L2] (4), [Cu(bipy)(H2O)L2] (5). According to the XRD data, the phosphinate anion L– exhibits a monodentate coordination in mononuclear complexes 2–5 and a bidentate-bridge coordination in the polymer complex 1. The cytotoxic activity of the ligands and complexes is studied using the A549 (carcinoma) and MRC5 (non-neoplastic fibroblasts) human lung cell lines. It is shown that the complexes exhibit pronounced dose-dependent cytotoxicity to these cell lines in the 1-50 µM concentration range. [ABSTRACT FROM AUTHOR]