反应详情

A suspension of methyl 6-[(2,2-diphenylethyl)amino]-9H-purine-2-carboxylate (Preparation 7) (1.5 g, 4.02 mmol) in 1,1,1-trichloroethane (40 ml) was treated with N,O-bis(trimethylsilyl)acetamide (4.8 ml, 19.6 mmol). The mixture was heated under reflux for two hours. The solution was allowed to cool to room temperature and the solvent removed under reduced pressure. The residue was taken up in anhydrous toluene (40 ml) and 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose (1.65 g, 5.19 mmol) and trimethylsilyl trifluoromethanesulfonate (0.98 ml, 5.43 mmol) added. The resulting solution was heated under reflux under a nitrogen atmosphere for 3 hours. The mixture was cooled to room temperature, diluted with ethyl acetate (200 ml) and washed with a saturated aqueous solution of sodium hydrogen carbonate. The organic layer was separated, dried over anhydrous magnesium sulphate, filtered and the solvent removed under reduced pressure. The residue was purified by column chromatography on silica gel using gradient elution with ethyl acetate:pentane (70:30, by volume) then ethyl acetate:pentane (80:20, by volume) then ethyl acetate to afford the title compound as a foam (2.05 g).

1. temperatureThe mixture was heated
2. temperatureunder reflux for two hours
3. customthe solvent removed under reduced pressure
4. temperatureThe resulting solution was heated
5. temperatureunder reflux under a nitrogen atmosphere for 3 hours
6. temperatureThe mixture was cooled to room temperature
7. washwashed with a saturated aqueous solution of sodium hydrogen carbonate
8. customThe organic layer was separated
9. dry with materialdried over anhydrous magnesium sulphate
10. filtrationfiltered
11. customthe solvent removed under reduced pressure
12. customThe residue was purified by column chromatography on silica gel using gradient elution with ethyl acetate:pentane (70:30, by volume)