In order to study the damaging or beneficial properties of bromine atom-free radical, reaction of the free radical (Br•) with some biologically important compounds were investigated. Br• was generated through electrochemical oxidation of bromide ion (Br–). First the reactivity of Br• atom-free radical vis a vis its dimerization to form Br2, was studied using cyclic voltammetry and spectroelectrochemistry. Through these techniques it was ascertained that the substrates understudy and the under experimental conditions used, underwent reactions with Br• and not with dibromine (Br2). The monitoring of the reactions of Br• with glycine and cytosine led us to conclude that whereas cytosine reacted with Br• as simple chemical reaction (EC mechanism), glycine underwent a catalytic reaction (EC' mechanism).

Reactive Intermediates Free Radical Chemistry Group International Center for Chemical and Biological Sciences H E J Research Institute of Chemistry 75270 Karachi Pakistan

Long-life atom-free radical: Generation and reactions of bromine atom-free radical

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