合成路线1

Pyrimidinone (III) was formed by condensation of benzamidine hydrochloride (I) with diethyl (ethoxymethylene)malonate (II). Subsequent reaction with glycinamide derivative (V) in the presence of p-tosyl chloride and Et3N afforded the aminopyrimidine (VI) (1). Alternatively, aminopyrimidine (VI) was prepared by chlorination of pyrimidinone (III) with POCl3, followed by displacement of the resulting chloropyrimidine (IV) with glycinamide (V) (2). Basic hydrolysis of the ethyl ester group of (VI) furnished pyrimidinecarboxylic acid (VII). This was then subjected to a Curtius rearrangement employing diphenyl phosphoryl azide (DPPA) to produce the 8-oxopurine system (VIII). Finally, N-alkylation of (VIII) with iodomethane gave rise to the title compound.