Theophyllinylpyrimidine Scaffolds Undergo Intramolecular Cyclization Reactions to Form 1,3-Diazepines and Imidazopurines

Polyheterocyclic pyrimidinyltheophyllines have been synthesized from pyrimidine and theophylline precursors. Attempts to cyclize these reactive bis-heterocyclic systems resulted in the formation of the corresponding diazepine moieties. In addition, modification of the reaction conditions led to the formation of imidazo[2,1-f]purines.