Platinum(II) and gold(I) complexes based on 1,1′-bis(diphenylphosphino)metallocene derivatives: Synthesis, characterization and biological activity of the gold complexes

The synthesis of series of 1,2,1′ substituted bis(diphenylphosphino)- ruthenocenyl (1–4) and ferrocenyl cis-platinum(II) (5–7) and gold(I) (8–12) complexes are described. Crystal structures of 2 and 4, as well as 5, 6 and 10 confirm the molecular geometry of these ligands and their metal complexes. Preliminary investigation of four gold complexes as potential anticancer, antiHIV and antimalaria showed at least one gold compound that has excellent activity towards one of these diseases. The three gold(I) complexes, {1- [1-(dimethylamino)ethyl]-1 ,2-bis(diphenylphosphino)ruthenocene-κ2P,P′}bis[chlorogold(I)] (8) (IC50 = 1.40 μM), {1-[1-(acetoxyethyl)-1′,2-bis(diphenylphosphino)ferrocene-κ2P,P′]bis[chlorogold(I)] (9) (IC50 = 0.51 μM), {1-[1-(3-carboxypropanamido)ethyl]-1′,2-bis(diphenylphosphino)-ruthenoceneκ2P,P′}bis[chlorogold(I)] (12) (IC50 = 1.784 μM), have the best activities against cancer, HIV and malaria respectively.