Antimicrobial and Antiproliferative Activities of New Benzimidazole-Bridged Aren Ruthenium Rectangles in Human Breast Cancer Cells

Some novel the benzimidazole-bridged aren ruthenium rectangles compounds of the general structure [{Ru2(p-cymene)2(µ4-OOᴖOO)}2(µ4-bbim)]4+ (bbim = 1,1'-butyl-2-ene-di(benzimidazole) were obtained from the corresponding double nuclear arene ruthenium compounds [Ru2(p-cymene)2(µ4-OOᴖOO)Cl2] (OOᴖOO = 2,5-dioxido-1,4-benzoquinonato (dobq),  2,5-dichloro-1,4-benzoquinonato (dClbq),  2,5-dibromo-1,4-benzoquinonato (dBrbq), oxalato (oxa), 5,8-dioxido-1,4-naphtoquinonato (donq) by reaction with the bbim molecule and AgCF3SO3. The antiproliferative activity of the tetranuclear arene ruthenium compounds was evaluated on their anti-cancer properties against human breast cancer cell line (MDA-231-MB), compound 2 showed the highest antiproliferative effect among the other compounds during 24 and 48 hours administration. Also, other all compounds showed very good cancer cell selectivity and very low micromolar cytotoxicities. In addition, antimicrobial activities of the synthesized compounds were determined. Against ten bacteria (such as Escherichia coli ATCC10536, Staphylococcus aureus ATCC 6538P, Staphylococcus epidermidis ATCC 12228, Klebsiella pneumoniae UC57, Proteus vulgaris ATCC 8427, Pseudomonas aureginosa ATCC 27853, Enterococcus faecalis ATCC 29212, Citrobacter freundii ATCC 8090, Mycobacterium smagmatis CCM 2067 and Listeria monocytogenes ATCC 15313) and seven yeast cultures (such as Candida glabrata ATCC 90030, Candida tropicalis ATCC 13803, Candida albicans ATCC 10231, Kluyveromyces fragilis NRRL 2415, Rhodotorula rubra DSM 70403, Debaryomyces hanseni DSM 70238, Hanseniaspora guillermondii DSM 3432). Using the disk diffusion method as well as the minimal inhibitory concentration (MIC) dilution method. Especially, the compounds exhibit potential antibacterial effects against Gram negative bacteria than Gram positive bacteria and showed superior antifungal effect agaist candida species.  The results revealed that the benzimidazole-bridged aren ruthenium rectangles compounds were the very strong potent inhibitor.