title: cis-[Rh2(mu-O2CCH3)2(CH3CN)6]2+ as a photoactivated cisplatin analog.
abstract: The complex cis-[Rh2(mu-O2CCH3)2(CH3CN)6]2+ (1) exchanges the two axial CH3CN ligands for solvent molecules in water to yield cis-[Rh2(mu-O2CCH3)2(CH3CN)4(H2O)2]2+ (2). Photolysis of 2 in H2O results in the photoaquation of two equatorial acetonitrile ligands to yield [Rh2(mu-O2CCH3)2(CH3CN)2(H2O)4]2+ (3), which is able to covalently bind to free 2,2'-bipyridine (bpy) and 9-ethylguanine in solution, as well as double-stranded DNA (lambdairr >/= 455 nm). Complex 2 exhibits 20-fold lower cytotoxicity towards human skin cells than hematoporphyrin in the dark, and its toxicity increases by a factor of 34 when irradiated with visible light (400-700 nm, 30 min). This increase in cytotoxicity by 2 upon irradiation is approximately 7 times greater than that measured for hematoporphyrin. These properties make 2 a promising photo-cisplatin analog and a potential agent for photodynamic therapy. To our knowledge, 2 is the first metal-metal bonded complex to bind to DNA upon irradiation with visible light.
authors.affiliation: Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Lutterman
authors.forename: Patty K-L
authors.initials: PK
authors.lastname: Fu
authors.forename: Claudia
authors.initials: C
authors.lastname: Turro
mesh_terms: D002945:Cisplatin / Q000031:analogs & derivatives* / Q000737:chemistry; D006801:Humans; D009942:Organometallic Compounds / Q000737:chemistry* / Q000494:pharmacology / Q000633:toxicity; D010777:Photochemistry; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D012867:Skin / Q000187:drug effects
chemical_list: D009942:Organometallic Compounds; D017319:Photosensitizing Agents; C509198:cis-(ruthenium(2)(mu-O2CCH3)2(CH3CN)6); D002945:Cisplatin