Efeito citotóxico contra células de câncer de pulmão de novos complexos de rutênio(II) contendo ligantes bifosfínicos, tiossemicarbazonas e semicarbazonas

Abstract

The present work describes the synthesis and physicochemical characterization of four novel and analogous ruthenium(II) complexes, containing in their coordination spheres biphosphine ligands (dppm = 1,1-bis (diphenylphosphine)methane and ligands of the cyclic thio and semicarbazone classes (5-methoxy-5,6-diphenyl-4,5-dihydro-2H-[1,2,4]triazine-3-thione (Btsc) and 5-methoxy-5,6-diphenyltriazine-3-one (Bsc), for complexes 1 and 2, respectively, and dppe= 1,1-bis(diphenylphosphine)ethane, Btsc and Bsc ligands, for complexes 3 and 4, respectively). The complexes were characterized by the techniques of elemental analysis, vibrational spectroscopy in the infrared region, absorption spectroscopy in the ultraviolet and visible region, 31P{1H} and 1H nuclear magnetic resonance spectroscopy, mass spectrometry and single crystal X ray diffraction. The stability of the complexes in dimethylsulfoxide (DMSO) was studied by obtaining the NMR 31P{1H} spectra in different periods of time. The study suggested that the bonds involved in the metal coordination sphere, in all complexes, remain unchanged during the monitored time interval. In vitro antitumor assays against the A549 (tumor cells) and BEAS-2B (normal cells) cells lineage were performed for all complexes, both precursors and free ligands and cisplatin. All evaluated complexes exhibited a cytotoxic effect against lung cancer cells, with IC50 values lower than cisplatin. The new complexes showed similar values in the range of 0.26 to 0.52 μM, being complex 4 the most active and selective among them. Molecular docking studies were performed to predict and understand possible interactions between complexes 1-4 and DNA.