title: Photochemical activities of N-nitroso carboxamides and sulfoximides and their application to DNA cleavage.
abstract: N-Nitroso compounds containing benzene, fluorene or fluorenone rings were synthesized. Photolysis of these compounds with 312-nm UV light provided the NO(*) species, the presence of which was corroborated by use of an EPR method and of 2-phenyl-4,4,5,5-tetramethylimidazolin-1-oxyl 3-oxide (PTIO) as a trapping agent. During irradiation of N-methyl-N-nitroso-9-fluorenone carboxamide (14 c) in the absence of PTIO, it underwent decomposition followed by recombination to give the heterocyclic nitric oxide radical 15. Incorporation of intercalating moieties endowed the N-nitroso compounds with DNA-cleaving ability through single-strand scission upon UV irradiation in a phosphate buffer (pH 5.0-8.0) under aerobic conditions.
authors: Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC. jrhwu@mx.nthu.edu.tw
authors: Jih Ru
authors: JR
authors: Hwu
authors: Joseph Jen-Tse
authors: JJ
authors: Huang
authors: Fu-Yuan
authors: FY
authors: Tsai
authors: Shwu-Chen
authors: SC
authors: Tsay
authors: Ming-Hua
authors: MH
authors: Hsu
authors: Kuo Chu
authors: KC
authors: Hwang
authors: Jia-Cherng
authors: JC
authors: Horng
authors: Ja-An Annie
authors: JA
authors: Ho
authors: Chun-Cheng
authors: CC
authors: Lin
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D004249:DNA Damage; D005449:Fluorenes / Q000737:chemistry; D009569:Nitric Oxide / Q000737:chemistry*; D009603:Nitroso Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D010782:Photolysis; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D000081:Acetamides; D005449:Fluorenes; D009603:Nitroso Compounds; D013438:Sulfhydryl Compounds; D009569:Nitric Oxide