LAUSR

Four novel monocationic Ru­(II) polypyridyl complexes were synthesized with the general formula [Ru­(DIP)2flv]­X, where DIP is 4,7-diphenyl-1,10-phenanthroline, flv stands for the flavonoid ligand (5-hydroxyflavone in [Ru­(DIP)2(5-OHF)]­(PF6), genistein in [Ru­(DIP)2(gen)]­(PF6), chrysin in [Ru­(DIP)2(chr)]­(OTf), and morin in [Ru­(DIP)2(mor)]­(OTf)), and X is the counterion, PF6−, and OTf (triflate, CF3SO3), respectively. Following the chemical characterization of the complexes by 1H and 13C NMR, mass spectrometry, and elemental analysis, their cytotoxicity was tested against several cancer cell lines. The most promising complex, [Ru­(DIP)2(gen)]­(PF6), was further investigated for its biological activity. Metabolic studies revealed that this complex severely impaired mitochondrial respiration and glycolysis processes, contrary to its precursor, Ru­(DIP)2Cl2, which showed a prominent effect only on the mitochondrial respiration. In addition, its preferential accumulation in MDA-MB-435S cells (a human melanoma cell line previously described as mammary gland/breast; derived from metastatic site: pleural effusion), which are used for the study of metastasis, explained the better activity in this cell line compared to MCF-7 (human, ductal carcinoma).