反应详情

The compound prepared as described in Example 2 (720 mg, 1.90 mmol) was dissolved in concentrated hydrochloric acid (14 ml). The resulting solution was heated under reflux for 8 hours. At the end of this time, the reaction mixture was neutralized with an aqueous solution of 1 N sodium hydroxide, and extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate and the solvent was removed by distillation under reduced pressure. The residue was purified by column chromatography through silica gel (eluent, ethyl acetate:methanol:isopropylamine=10:1:1), to give the title compound (Rf=0.45, 255 mg) as a white powder (yield 37%).

1. customThe compound prepared
2. temperatureThe resulting solution was heated
3. temperatureunder reflux for 8 hours
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with water
6. dry with materialdried over anhydrous sodium sulfate
7. customthe solvent was removed by distillation under reduced pressure
8. customThe residue was purified by column chromatography through silica gel (eluent, ethyl acetate:methanol:isopropylamine=10:1:1)