DAVOODNIA, A.; BAKAVOLI, M.; KHASHI, M.; MOLOUDI, R.; TAVAKOLI-HOSEINI, N. Synthesis of Pyrrolo[2,3-d]pyrimidin-4-ones(7-Deazapurines) Under Solvent- and Catalyst-Free Conditions. ajc 2010, 22, 4625-4628.