反应详情

A solution of Compound 157 (0.250 g, 0.69 mmol) in 1,2-dichloroethane was added with tetrahydro-4-pyranone (0.096 mL, 1.04 mmol) followed by stirring for 15 minutes. The mixture was added with sodium triacetoxyborohydride (0.439 g, 2.07 mmol) followed by stirring at room temperature for 5 hours. The reaction mixture was added with a 2 mol/L aqueous sodium hydroxide solution and extracted with dichloromethane three times. The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform:2 mol/L ammonia-methanol solution=19:1). The obtained crystals were recrystallized from ethanol-diisopropyl ether to obtain Compound 158 (0.166 g, 0.37 mmol, 54%).

1. stirringby stirring at room temperature for 5 hours
2. extractionextracted with dichloromethane three times
3. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by silica gel column chromatography (chloroform:2 mol/L ammonia-methanol solution=19:1)
6. customThe obtained crystals were recrystallized from ethanol-diisopropyl ether