Oxidation chemistry of adenine N1-oxide, a potent oncogenic agent, at a pyrolytic graphite electrode

Abstract

The electrochemical oxidation of adenine N¹-oxide has been studied at a pyrolytic graphite electrode in phosphate buffers of pH range 1.4–9.8. In cyclic voltammetry (CV) more than one oxidation peak was noticed in the acidic pH range and a single oxidation peak was observed in the neutral and alkaline pH range. The kinetics of decay of the UV-absorbing intermediate generated during electrooxidation has been studied at different pH and the decay occurred in a pseudo-first-order reaction. At pH 3.0, the electrooxidation products were characterized as alloxan-N¹-oxide, urea and alloxan in a 6e, 6H⁺ process. However, at pH 7.0, the number of electrons involved in the oxidation was found to be ∼ 2.7 per mole and a dihydroxytrimer has been characterized as the major product. A detailed interpretation of the redox mechanism for the formation of the products has also been suggested.