反应详情

The compound (3.5 g, 21.0 mmol) obtained in Step 1 above was dissolved in 5N aqueous sodium hydroxide solution (40 ml) and benzyloxycarbonyl chloride (3.3 ml, 23.0 mmol) was added dropwise at 0° C. After stirring at room temperature for 16 hours, the reaction mixture was rendered acidic by addition of 1N hydrochloric acid, followed by extraction with ethyl acetate. The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, diethyl ether and hexane were added to the residue obtained and then the slurry was filtered and dried to give 2.06 g (37%) of the title compound as a colorless solid.

1. extractionfollowed by extraction with ethyl acetate
2. washThe organic layer was washed with brine
3. dry with materialdried over anhydrous magnesium sulfate
4. customThe solvent was evaporated under reduced pressure, diethyl ether and hexane
5. additionwere added to the residue
6. customobtained
7. filtrationthe slurry was filtered
8. customdried