The reactions of hydroxyl radicals with 5-nitrouracil, 5-nitrobarbituric acid, and 6-nitro-2-furoic acid in aqueous solutions have been studied by conductometric pulse radiolysis and by determination of the yield of nitrate in irradiated solutions. Addition of OH to the position bearing the nitro group was found to be followed by immediate elimination of HNO2. This path accounts for 25% of the OH reaction with 5-nitrouracil and 75% with 5-nitro-2-furoic acid. An additional yield of nitrite is, however, produced on the time scale of the decay of the organic radicals and the total yield reaches 85% of G(OH) for both the nitrouracil and the nitrofuroic acid. This slower formation of nitrite is a result of radical disproportionation by electron transfer. This mechanism was found to be pH dependent with the yield for nitrite formation decreasing in acid solutions.

This content is only available as a PDF.
You do not currently have access to this content.