Structural studies and cytotoxic activity against human cancer cell lines of mono and dinuclear tin(IV) complexes with the α,α′-dimercapto-o-xylene ligand

Abstract

The reaction of α,α′-dimercapto-o-xylene (H2dmox) with SnPh2Cl2 (1:1) and SnPh3Cl (1:2) in the presence of two equivalents of NEt3 led to the formation of the complexes [SnPh2(dmox)] (1) and [SnPh3(μ-dmox)]2 (2), respectively. Both complexes have been characterized by multinuclear NMR and IR spectroscopy, mass spectrometry and elemental analysis. In addition, the molecular structure of complex 2 has been determined by single crystal X-ray diffraction studies. The cytotoxic activity of 1 and 2 was tested against the tumor cell lines human cervix adenocarcinoma HeLa, breast carcinoma MDA-MB-453, colon carcinoma LS174 and human myelogenous leukemia K562. In addition, the toxicity of both complexes to non-stimulated and stimulated peripheral blood mononuclear cells (PBMC) has been tested. The in vitro cytotoxicity tests show very high antiproliferative activity of both complexes, being much higher that of 2. In addition, this compound shows a higher cytotoxic activity towards cancer cell lines than to non-stimulated and stimulated PBMC, indicating a slight selectivity to cancer cell lines.