Ru, Rh and Ir metal complexes of pyridyl chalcone derivatives: Their potent antibacterial activity, comparable cytotoxicity potency and selectivity to cisplatin

Half sandwich ruthenium, rhodium and iridium complexes containing pyridyl chalcone analogues (L1 and L2) are prepared by the reaction of [(arene)M(µ-Cl)Cl]2 (arene = benzene, p-cymene, Cp*) and (M = Ru, Rh/Ir)] with L1 and L2 in 1:2 (M:L) ratio. Eight neutral mononuclear complexes (1–8) were obtained and characterized using FT-IR, 1H NMR, 13C NMR, ESI mass and UV–Vis spectroscopic methods. The molecular structures of complexes 2, 4, 5 and 7 are established by single crystal X-ray diffraction studies. Antibacterial studies were tested against three strains of bacterial microorganisms Staphylococcus aureus (gram +ve), Klebsiella pneumoniae (gram −ve) and Escherichia coli (gram −ve). Further the cytotoxicity study of the pyridyl chalcone derivatives and their complexes were evaluated against the human colorectal cancer cell lines HT-29, HCT-116 p53+/+, HCT-116 p53−/− and ARPE-19 (non-cancer retinal epithelium).