反应详情

To a suspension of 395 g. (1.12 moles) of 9-benzyl-1,3-dimethyl-6-(hydroxy)pyrimido[2,1-f]purine-2,4,8(1H,3H,9H)-trione in 10.5 liters of dry 1,4-dioxane, add 68.1 g. (3.14 moles) of lithium borohydride in portions. Maintain the reaction temperature at 20°-25° C. by controlling the rate of addition and by use of a cooling bath as needed. Stir the mixture at room temperature for 0.5 hour, then reflux for 18 hours. Remove solvent under reduced pressure. Allow the residue to cool; then add 4.5 liters of chloroform. To the resultant mixture, cautiously add dropwise 1.1 liters of water. Stir the mixture at room temperature until two clear phases result. Add 3N hydrochloric acid portionwise to bring the pH to 4-5. Separate the layers, and extract the aqueous phase with two 1.1-liter portions of chloroform. Wash the combined extracts with three 1.1-liter volumes of water, and dry over anhydrous sodium sulfate. Filter the drying agent, and remove volatiles from the filtrate under reduced pressure. Crystallize the residue from methanol-ethyl acetate to obtain title compound (I) as a solid with m.p. 176°-182° C.

1. additionTo a suspension of 395 g
2. temperatureMaintain the reaction temperature at 20°-25° C.
3. additionthe rate of addition
4. customby use of a cooling bath as needed
5. temperaturereflux for 18 hours
6. temperatureto cool
7. stirringStir the mixture at room temperature until two clear phases
8. customresult
9. customSeparate the layers
10. extractionextract the aqueous phase with two 1.1-liter portions of chloroform
11. washWash the combined extracts with three 1.1-liter volumes of water
12. dry with materialdry over anhydrous sodium sulfate
13. filtrationFilter the drying agent
14. customremove volatiles from the filtrate under reduced pressure
15. customCrystallize the residue from methanol-ethyl acetate