Synthesis and biological evaluation of platinum(II) complexes containing (1R,2R)-N1-alkyl-1,2-diaminocyclohexane and D-(+)-camphorate ligands

Five platinum(II) complexes with N-monoalkyl derivatives of 1R,2R-diaminocyclohexane as ligands and D-(+)-camphorate anion as leaving group have been synthesized and characterized by elemental analysis, IR, 1H NMR, ESI-MS, and HRMS spectra. All complexes were evaluated for their in vitro cytotoxicity against four human tumor cell lines and most of them showed promising cytotoxic activity, especially compounds 3 and 4 with branched alkyl substituent at one of nitrogen atoms. Preliminary mechanism study by flow cytometry and agarose gel electrophoresis was also carried out in comparison with cisplatin and oxaliplatin.