A study on the reaction of adenine with ethylene oxide or with ethylene carbonate at different molar ratios of reagents is described. For both pairs of reagents, nominally, the same products were obtained. At first, N(9)-2-hydroxyethyl derivative of adenine was obtained, and then, polyetherols containing purine rings. The main difference between the reactions carried out using the oxide and carbonate was the resulting substitution degree of amine group. The course of both types of reactions was followed using H-1 NMR spectroscopy to determine the contents of amine, hydroxyl, and methylene groups in the products of reactions. (C) 2002 Elsevier Science B.V. All rights reserved.