Synthesis, anticancer activity and apoptosis induction of gold(I) complexes containing tris(o-methoxyphenyl)phosphane

Abstract Four new phosphanegold(I) complexes; [Au{(o-MeO-Ph)3P}Cl] (1), [Au{(o-MeO-Ph)3P}{(Me-Et-Ph)P}]Cl (2), [Au{(o-MeO-Ph)3P}(Ph3P)]Cl (3) and [Au{(o-MeO-Ph)3P}2]Cl (4) (where o-MeO-Ph)3P = tris(o-methoxyphenyl)phosphane and (Me-Et-Ph)P = methylethylphenylphosphane) were prepared and characterized by elemental analysis, FTIR and NMR spectroscopy. The structure of one of the complexes was determined by X-ray crystallography, which showed that the gold(I) atom is linearly coordinated to the phosphorus and Cl atoms. The in vitro cytotoxicity of the complexes was investigated against four human cancer cell lines; A549, HeLa, MDA-MB-231 and MCF7. In all cases, the tested complexes showed excellent cytotoxicity for the selected cells, with IC50 values much less than cisplatin. In order to know the possible mode of cell death, complex 1 was further evaluated for induction of apoptosis towards the A549 cells. The results indicated that the apoptosis induction increases with the complex concentration.