Abstract：
:3-Alkyl-1,2,3-oxadiazolinium ions 1 have been proposed as reactive intermediates in the activation of (2-hydroxyethyl)nitrosamines. The reaction of 3-methyl-1,2,3-oxadiazolinium tosylate (1a), 2-ethyl-1-methoxy-2-phenyldiazenium tetrafluoroborate (3), and 3-phenyl-1,2,3-oxadiazolinium triflate (1b) with thiols was investigated to determine the behavior of these compounds toward typical "cellular nucleophiles". Each of these substances oxidizes benzenethiol to diphenyl disulfide. The reaction in aqueous buffer at pH 7.4 is rapid. Reaction of 1b with benzenethiol gives, in addition to the disulfide, benzene, biphenyl, azobenzene, diphenyl sulfide, aniline, and glycolaldehyde. Similar products are obtained from 3. Phenyldiazene is postulated as an intermediate in this process, and its generation from phenyldiazoformate in the presence of benzenethiol gives similar products. Diazenes are presumed to arise by proton abstraction from the CH adjacent to N. The kinetics of reaction of 1a with N-acetylcysteine to give the corresponding disulfide show first order dependence on each reactant and base catalysis. The data from these model chemical experiments suggest that 1,2,3-oxadiazolinium ions could react with abundant thiols in cells to lead to either their detoxification or radical processes emanating from diazenes. The occurrence of thiol-oxadiazolinium ion redox transformations could modulate the alkylation chemistry of these substances as well.
journal_name
Chem Res Toxicoljournal_title
Chemical research in toxicologyauthors
Loeppky RN,Srinivasan Adoi
10.1021/tx00048a001subject
Has Abstractpub_date
1995-09-01 00:00:00pages
817-20issue
6eissn
0893-228Xissn
1520-5010journal_volume
8pub_type
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更新日期：1994-01-01 00:00:00
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更新日期：2011-03-21 00:00:00
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更新日期：1996-09-01 00:00:00
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更新日期：2012-07-16 00:00:00
