Synthesis and cytotoxicity of new Pt(IV) complexes of 2,2′-biimidazole and derivatives

Compounds of type [PtCl4(LL)] [LL = 2,2′-biimidazole (H2bim), N-methyl-2,2′-biimidazole (MeHbim), N-hydroxyethyl-2,2′-biimidazole (HOEtHbim), or N,N′-dimethyl-2,2′-biimidazole (Me2bim)] were prepared and characterized. The structure of [PtCl4(Me2bim)] was determined by X-ray diffractometry. The new compounds were tested for cytotoxicity against the human ovarian cancer cell line A2780 and the cisplatin-resistant line A2780cis. All of them, except the HOEtHbim derivative, circumvent cisplatin-induced resistance.