124-41-4

100644-65-3

100644-67-5

The general procedure for the synthesis of 4-methoxy-1H-pyrazolo[3,4-d]pyrimidin-6-amine from sodium methanol and 4-chloro-1H-pyrazolo[3,4-d]pyrimidin-6-amine was as follows: 4-chloro-1H-pyrazolo[3,4-d]pyrimidin-6-amine (800 mg, 4.73 mmol) was dissolved in 12.5 mL anhydrous methanol and purged with nitrogen to remove the oxygen. Subsequently, the solution was transferred to a methanol solution containing 2.3 M sodium methanol. After the reaction was refluxed at 65 °C for 2 h, 7.5 mL of acetic acid was slowly added and stirring was continued for 5 min. Upon completion of the reaction, the solvent was removed by rotary evaporation and dried under vacuum to give 745 mg of tan solid product in 95.4% yield.