title: Anticancer activity of osmium metalla-rectangles.
abstract: A series of cationic metalla-rectangles of the general formula [(p-cymene)(4)Os(4)(OO[intersection]OO)(2)(N[intersection]N)(2)](4+) have been obtained in methanol from the dinuclear arene osmium precursors [(p-cymene)(2)Os(2)(OO[intersection]OO)(2)Cl(2)] (OO[intersection]OO = 2,5-dioxydo-1,4-benzoquinonato (dhbq), 2,5-dichloro-1,4-benzoquinonato (dcbq)) by reaction with bipyridine linkers (N[intersection]N = 4,4'-bipyridine, 1,2-bis(4-pyridyl)ethylene) in the presence of AgCF(3)SO(3). All complexes were isolated as triflate salts and characterised by NMR, IR and UV-visible spectroscopy. The cytotoxicities of the dinuclear and tetranuclear osmium complexes were established using ovarian A2780 cancer cell lines. The most active metalla-rectangle, [(p-cymene)(4)Os(4)(dhbq)(2)(4,4'-bipyridine)(2)](4+), shows an IC(50) value of 5.7 microM (comparable to cisplatin) against A2780 cancer cells and 7.5 microM against the cisplatin resistant A2780cisR cells.
authors.affiliation: Institute of Chemistry, University of Neuchatel, 51 Ave de Bellevaux, CH-2000, Neuchatel, Switzerland.
authors.forename: Nicolas P E
authors.initials: NP
authors.lastname: Barry
authors.forename: Fabio
authors.initials: F
authors.lastname: Edafe
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Dyson
authors.forename: Bruno
authors.initials: B
authors.lastname: Therrien
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D002412:Cations / Q000737:chemistry; D045744:Cell Line, Tumor; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009992:Osmium / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000970:Antineoplastic Agents; D002412:Cations; D056831:Coordination Complexes; D011725:Pyridines; D009992:Osmium; C023666:pyridine