Reactions of Dichioride Anion Radicals with Pyrimidine and its Derivatives

概要

論文の詳細を見る
Rate constants for the reactions of dichloride anion radicals with pyrimidine and its derivatives were determined by a conventional flash photolysis. Kinetic treatment was carried out by assuming that second-order self decay of the anion radicals and the reaction with a substrate proceed simultaneously. Values of the rate constants were found within 1.1 x 10^7 to 4.1 x 1O^9 M^<-1> s^<-1>; the lowest reactivity was observed for pyrimidine and the highest for 2, 4, 6-triaminopyrimidine. Comparison of the rate constants with those for hydroxyl radicals suggests that the dichloride anion radicals undergo a different reaction with pyrimidine bases from that of the hydroxyl radicals. A transient absorption due to an intermediate produced in the reaction with the anion radicals was observed for 5-aminouradil. This is only a case where relatively long-lived absorption was observed. The absorption was used to determine the rate constants for the reactions with the anion radicals.
日本放射線影響学会の論文