Synthesis, characterization, and anticancer activity of ruthenium-pyrazole complexes

A series of new water soluble Ru(III) pyrazole complexes mer-[RuCl3(DMSO-S)(pyz)2] 1, mer-[RuCl3(DMSO-S)(DMSO-O)(pyz)] 2, mer-[RuCl3(bpy)(dmpyz)] 3, and mer-[RuCl3(DMSO-S)(dmpyz)2] 4 (pyz = pyrazole; dmpyz = 3,5-dimethylpyrazole, bpy = 2,2’-bipyridine) have been synthesized and characterized by use of a combination of spectroscopy (IR and UV-visible), X-ray diffraction, and cyclic voltammetry. The molecular X-ray structure of all reported compounds (1–4) revealed distorted octahedral coordination around ruthenium. The cytotoxicity assay on human breast cancer cells (MCF7) demonstrated that compounds 1 and 4 affect cell viability, whereas compounds 2 and 3 do not show appreciable activity. The IC50 values for 1 and 4 lie within the range of 71–32 μM in MCF7 cells.

Several water soluble Ru(III)-DMSO-Pyrazoles complexes have been prepared and characterized. Two of the complexes (1 and 4) have been found to have in vitro cytotoxicity against MCF7 human cancer cell lines.Figure optionsDownload as PowerPoint slideHighlights
► Four new neutral water soluble ruthenium-DMSO-pyrazole complexes are prepared.
► The geometry of all the four complexes are distorted octahedral with meridonial arrangement.
► The result of in vitro cytotoxicity testing showed that compounds 1 and 4 show significant cytotoxicity to the MCF7 breast cancer cells, whereas compounds 2 and 3 do not show appreciable anticancer activity to tested cancer cell lines.