919278-72-1

871024-38-3

919278-72-1

4-Chloro-5-methyl-5H-pyrrolo[3,2-d]pyrimidine (3.30 g, 19.7 mmol) was used as starting material, which was mixed with 6 N aqueous hydrochloric acid (20 mL) and the reaction was stirred for 1 h at 120 °C. The reaction was carried out at 120 °C with the addition of 8 N aqueous sodium hydroxide. Upon completion of the reaction, the reaction solution was cooled to 0 °C and the pH was adjusted slowly to 7 by adding 8 N aqueous sodium hydroxide solution.Subsequently, the reaction mixture was filtered to collect the precipitated solid product, which was washed several times with deionized water, and dried to afford the target compound, 5-methyl-3H-pyrrolo[3,2-d]pyrimidin-4(5H)-one (2.60 g, 88% yield), as a yellow solid. The product was characterized by 1H-NMR (DMSO-d6, 300 MHz): δ 3.99 (3H, s), 6.31 (1H, d, J = 2.7 Hz), 7.35 (1H, d, J = 2.7 Hz), 7.73 (1H, d, J = 3.0 Hz), 11.81 (1H, br s).