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 degrees C in neutral aqueous solutions are reported. The biological implications of the results obtained are also discussed. (c) 2008 Elsevier Ltd. All rights reserved.