Anti-cancer gold(I) phosphine complexes: Cyclic trimers and tetramers containing the P-Au-P moiety

We report the application of cationic tri- and tetra-nuclear gold(I) phosphine complexes [Au 3 (μ-dppen) 3 ]X 3 and [Au 4 (μ-dppa) 4 ]X 4 (X = OTf, PF 6 ) [OTf = trifluoromethanesulfonate, dppen = trans-1,2-bis(diphenylphosphino)ethene, dppa = bis(diphenylphosphino)acetylene] for cancer treatment. The results of cytotoxicity tests on four different cancer cells [prostate (DU145), cervical (HeLa), breast (MDAMB-231) and fibro sarcoma (HT1080)] indicate these complexes possess remarkable tumor cell growth inhibitory effects and high selectivity towards cancer cells. The anti-tumor mechanism of the tri- and tetra-nuclear gold(I) complexes has also been investigated.