Abstract
An improved method for the synthesis of 5-aminocytidine, 5-amino-2''-deoxycytidine and their 5''-monophosphates from the corresponding 5-bromo pyrimidines, using liquid ammonia, is described. [Modifications of cytosine nucleosides and nucleotides have led to a variety of useful antimetabolites and enzyme inhibitors]. The respective 6-aminocytosine derivatives, minor products of the amination reaction, were isolated and characterized. A plausible mechanism is proposed to account for the formation of both 5- and 6-substituted products.