7791-49-3Relevant academic research and scientific papers
Cu-Catalyzed π-Core Evolution of Benzoxadiazoles with Diaryliodonium Salts for Regioselective Synthesis of Phenazine Scaffolds
Sheng, Jinyu,He, Ru,Xue, Jie,Wu, Chao,Qiao, Juan,Chen, Chao
supporting information, p. 4458 - 4461 (2018/08/09)
The Cu-catalyzed regioselective synthesis of phenazine N-oxides was realized from benzoxadiazoles and diaryliodonium salts. The process was initiated by the electrophilic arylation of benzoxadiazoles with diaryliodonium salts and followed by benzocyclization reactions. The further reduction of N-oxides in situ to phenazine scaffolds and deviation to organic fluorescent materials were readily accomplished.
Hypoxia-Selective Agents Derived from Quinoxaline 1,4-Di-N-oxides
Monge, Antonio,Palop, Juan A.,Cerain, Adela Lopez de,Senador, Virginia,Martinez-Crespo, Francisko J.,et al.
, p. 1786 - 1792 (2007/10/02)
Hypoxic cells, which are a common feature of solid tumors, but not normal tissues, are resistant to both anticancer drugs and radiation therapy.Thus the identification of drugs with selective toxicity toward hypoxic cells is an important objective in anticancer chemotherapy.The benzotriazine di-N-oxide (SR 4233, Tirapazamine) has been shown to be an efficient and selective cytotoxin for hypoxic cells.Since the bioreductive activation of Tirapazamine is thought to be due to the presence of the 1,4-di-N-oxide moiety, a series of 3-aminoquinoxaline-2-carbonitrile 1,4-di-N-oxides with a range of electron-donating and -withdrawing substituents in the 6- and /or 7- positions has been synthesized and evaluated for toxicity to hypoxic cells.Electrochemical studies of the quinoxaline di-N-oxides and Tirapazamine showed that as the electron-withdrawing nature of the 6(7)-substituent increases, the reduction potential becomes more positive and the compound is more readily reduced.Apart from the unsubstituted 6a and the 6,7-dimethyl derivative 6c, the quinoxaline di-N-oxide have reduction potentials significantly more positive than Tirapazamine (Epc -0.90 V).The most potent cytotoxins to cells in culture were the 6,7-dichloro and 6,7-difluoro derivatives 6i and 6l, which were 30-fold more potent than Tirapazamine.The 6(7)-fluoro and 6(7)-chloro compounds, 6e and 6h, showed the greatest hypoxia selectivity.Four of the compounds, 6e, 6f, 6h and 6i, killed the inner cells of multicellular tumor spheroids in vitro.In vivo Balb/c mice tolerated a dose of these four compounds twice the size of that of Tirapazamine.This study demonstrates that quinoxaline 1,4-di-N-oxides could provide useful hypoxia-selective therapeutic agents.
Pyrolysis of Aryl Azides. VII. Interpretation of Hammett Correlations of Rates of Pyrolysis of Substituted 2-Nitroazidobenzenes
Dyall, Leonard K.
, p. 89 - 101 (2007/10/02)
Rates and products of pyrolysis have been obtained for ten 2-nitroazidobenzenes with 4- or 5-substituents.Rate data at 100 deg C are correlated with Hammett constants of the 4- and 5-substituents, with respect to both the azido (A) and nitro (N) reaction
