Platinum(0)-η 2 -1,2-( E )ditosylethene Complexes Bearing Phosphine, Isocyanide and N -Heterocyclic Carbene Ligands: Synthesis and Cytotoxicity towards Ovarian and Breast Cancer Cells.

A wide range of platinum(0)-η 2 -( E )-1,2-ditosylethene complexes bearing isocyanide, phosphine and N -heterocyclic carbene ancillary ligands have been prepared with high yields and selectivity. All the novel products underwent thorough characterization using spectroscopic techniques, including NMR and FT-IR analyses. Additionally, for some compounds, the solid-state structures were elucidated through X-ray diffractometry. The synthesized complexes were successively evaluated for their potential as anticancer agents against two ovarian cancer cell lines (A2780 and A2780 cis ) and one breast cancer cell line (MDA-MB-231). The majority of the compounds displayed promising cytotoxicity within the micromolar range against A2780 and MDA-MB-231 cells, with IC 50 values comparable to or even surpassing those of cisplatin. However, only a subset of compounds was cytotoxic against cisplatin-resistant cancer cells (A2780 cis ). Furthermore, the assessment of antiproliferative activity on MRC-5 normal cells revealed certain compounds to exhibit in vitro selectivity. Notably, complexes 3d , 6a and 6b showed low cytotoxicity towards normal cells (IC 50 > 100 µM) while concurrently displaying potent cytotoxicity against cancer cells.