反应详情

5-methyl-3-(phenylamino)-1H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (4.3 g, 16.7 mmol) is refluxed in POCl3 (120 mL) for 2 days, and then POCl3 is removed under reduced pressure. The residue is suspended in 100 mL of water and carefully adjusted to pH=1˜2 with 7% NH4OH upon cooling. The mixture is then extracted with CH2Cl2 and MeOH (10:1, v/v) five times. The combined organic phase is washed with water, dried over Na2SO4, and then evaporated under reduced vacuum to give 3.3 g of crude product (Yield: 72%). MS (ESI) m/z 276.1 [M+H]+.

1. customPOCl3 is removed under reduced pressure
2. temperatureupon cooling
3. extractionThe mixture is then extracted with CH2Cl2 and MeOH (10:1
4. washThe combined organic phase is washed with water
5. dry with materialdried over Na2SO4
6. customevaporated under reduced vacuum