反应详情

The compound (47.2 mg) obtained in Example 91-1 was dissolved in methanol (1.0 ml) and trimethyl orthoformate (28.0 μl) and a methanol solution containing the compound (14.7 mg) obtained in Example 1-2 were dropped thereto at room temperature under a nitrogen atmosphere. The whole was stirred for 12 hours. Sodium borohydride (10.0 mg) was added thereto under ice-cooling and the whole was warmed back to room temperature and stirred for 2 hours. After completion of the reaction, water was added thereto. The solvent was distilled off under reduced pressure. The resultant was diluted with chloroform and added with water, and the aqueous layer was subjected to extraction with chloroform. The combined organic layer was washed with a saturated saline solution and dried with anhydrous sodium sulfate. After filtration, the solution was concentrated and evaporated to dryness under reduced pressure and the residue was purified through silica gel column chromatography (chloroform/methanol), thereby obtaining the subject compound (51.6 mg) as a pale-yellow solid.

1. additionwere dropped
2. customat room temperature
3. temperatureunder ice-cooling
4. stirringstirred for 2 hours
5. additionwas added
6. distillationThe solvent was distilled off under reduced pressure
7. additionThe resultant was diluted with chloroform
8. additionadded with water
9. extractionthe aqueous layer was subjected to extraction with chloroform
10. washThe combined organic layer was washed with a saturated saline solution
11. dry with materialdried with anhydrous sodium sulfate
12. filtrationAfter filtration
13. concentrationthe solution was concentrated
14. customevaporated to dryness under reduced pressure
15. customthe residue was purified through silica gel column chromatography (chloroform/methanol)