Synthesis, structures and in vitro cytotoxicity of some cationic cis-platinum(II) complexes containing chelating thiocarbamates

The thiocarbamates 4-RC 6H 4NHC(S)NR 2′ (R = H, Cl; R′ = Me, Et), 4-ClC 6H 4NHC(S)NR (NR = 2-pyridylpiperazine) react with cis-[PtCl 2(PTA) 2] (PTA = 1,3,5-triaza-7-phosphaadamantane) in the presence of base to afford the monocationic platinum(II) complexes cis-[Pt{SC(NR 2′) = NC 6H 4R}(PTA) 2] + (R = H, Cl; R′ = Me, Et), cis-[Pt{SC(NR) = NC 6H 4Cl}(PTA) 2] + (NR = 2-pyridylpiperazine), which were isolated as their PF 6 salts in high yields. The complexes were fully characterised spectroscopically and also by X-ray crystallography. Cytotoxicity of these complexes was studied in vitro in three human cancer cell lines (CH1, A549 and SW480) using the MTT assay. The monocationic platinum(II) complexes cis-[Pt{SC(NR 2′) = NC 6H 4R}(PTA) 2] + (R = H, Cl; R′ = Me, Et) and cis-[Pt{SC(NR) = NC 6H 4Cl}(PTA) 2] + (NR = 2-pyridylpiperazine) containing the cage phosphine PTA (1,3,5-triaza-7-phosphaadamantane) were prepared and their in vitro cytotoxicity was studied. [Display omitted]