Stanislav Grabovskiy - 5-Aminouracil as effective inhibitor of peroxyl radicals. experimental and theoretical studies

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      Publication Details (including relevant citation   information):

      Curr. Org. Chem., 2012, 16 (11), pp. 1447-1452.

      DOI: 10.2174/138527212800672619

      Abstract:

      The reaction of 5-aminouracil with peroxyl   radicals generated by the thermal decomposition of   2,2'-azo-bis(2- methylpropionitrile) (AIBN) and   2,2'-azo-bis(2-amidinopropane) dihydrochloride was studied at   50°C in ethanol and water (pH 7.0) solution respectively. The   oxidation product of 5-aminouracil formed by peroxyl radicals was   dihydro-5,5,6-trihydroxypyrimidine-2,4-dione. The relative rate   constant of 5-aminouracil vs. quercetin and   2,6-di-tert-butyl-4-methylphenol by peroxyl radicals generated   from AIBN was measured in ethanol and found to be 0.19 (50°C) and   3.6 (70°C) respectively. Theoretical data of the redox potential   and the bound dissociation energy oppose against single   electron/proton transfer mechanism and provide support for a   hydrogen atom abstraction mechanism. Transition structures and   activation barriers of the hydrogen abstraction from   5-aminouracil, 5-hydroxy-6-methyluracil and   2,6-di-tert-butyl-4-methylphenol by methyl peroxyl radical were   determined with the BB1K/6-31+G(d,p) level of theory. The   relative theoretical reactivity was found to be in a good   agreement with the experimental results and also supported the   hydrogen abstraction mechanism.

      Address (URL): http://www.eurekaselect.com/98371/article