Reaction between 7,8-dihydropterins and hydrogen peroxide under physiological conditions

In vitiligo, a common skin disorder that produces white patches of depigmentation, 7,8-dihydropterins accumulate in the presence of high concentration of H₂O₂. In this work, we present a study of the reaction between 7,8-dihydropterins and H₂O₂. The rate of the reaction, as well as the products formed, strongly depend on the chemical structure of the substituents. Electron-donor groups as substituents are the most reactive derivatives and undergo oxidation of the pterin moiety. The corresponding bimolecular rate constants at 37 °C in neutral aqueous solutions are reported. The biological implications of the results obtained are also discussed.