Syntheses and Properties of 3-Hydroxy-4, 6-dimethylpyrrolo [3, 2-d] pyrimidine-5, 7 (4H, 6H)-dione (9-Hydroxy-9-deazatheophylline) Derivatives

Treatment of 1, 3, 6-trimethyl-5-nitrouracil with aryl aldehydes in the presence of piperidine results in condensation to the 5-nitro-6-styryluracil derivatives, followed by intramolecular cyclization including piperidine-catalyzed oxidation-reduction to give rise to the corresponding 3-hydroxy-4, 6-dimethylpyrrolo [3, 2-d] pyrimidine-5, 7 (4H, 6H)-dione (9-hydroxy-9-deazatheophylline) derivatives in a single step. Some properties of these compounds and an X-ray crystal structure determination of 8-(p-chlorophenyl)-9-methoxy-7-methyl-9-deazatheophylline are described.