反应详情

1 N Sulfuric acid (1 mL) was added to a stirred solution of 5-(2-butoxy-5-ethynyl-3-pyridinyl)-2-[2-(dimethylamino)ethyl]-3-ethyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (Example 46) (280 mg, 0.69 mmol) in acetone (8 mL) at room temperature. Mercury sulfate (40 mg, 0.14 mmol) was added and the mixture heated at reflux for 5 h. The reaction mixture was cooled, diluted with methanol (10 mL), filtered and the filtrate washed with further methanol. The solvent was evaporated and the residue partitioned between ethyl acetate (100 mL) and saturated sodium bicarbonate solution (100 mL). The aqueous was washed with a further 100 mL of ethyl acetate and the combined organics dried (MgSO4) and concentrated. Purification by flash column chromatography (elution with 95% dichloromethane/methanol) gave the product as a cream coloured solid (140 mg).

1. temperaturethe mixture heated
2. temperatureat reflux for 5 h
3. temperatureThe reaction mixture was cooled
4. filtrationfiltered
5. washthe filtrate washed with further methanol
6. customThe solvent was evaporated
7. customthe residue partitioned between ethyl acetate (100 mL) and saturated sodium bicarbonate solution (100 mL)
8. washThe aqueous was washed with a further 100 mL of ethyl acetate
9. dry with materialthe combined organics dried (MgSO4)
10. concentrationconcentrated
11. customPurification
12. washby flash column chromatography (elution with 95% dichloromethane/methanol)
13. customgave the product as a cream