反应详情

A mixed solution of ethyl 4-hydroxy-3-methyl-1-(2-pyridinyl)-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (1.5 g, 5.0 mmol) and cyclohexylamine (2.2 g, 22 mmol) in xylene (5.0 mL) and dimethylsulfoxide (5.0 mL) was stirred at 130° C. for 28 hours. The solution was cooled to room temperature and water was added thereto. Subsequently, organic matter was extracted with ethyl acetate. The extract was washed with saturated brine and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purification of the residue by silica gel column chromatography (chloroform:methanol=50:1 to 20:1) gave crude crystals. The crude crystals were recrystallized from ethyl acetate/ethanol to give the title compound (0.17 g, 10% yield).

1. extractionSubsequently, organic matter was extracted with ethyl acetate
2. washThe extract was washed with saturated brine
3. dry with materialdried over anhydrous sodium sulfate
4. customthe solvent was evaporated under reduced pressure
5. customPurification of the residue by silica gel column chromatography (chloroform:methanol=50:1 to 20:1)
6. customgave crude crystals
7. customThe crude crystals were recrystallized from ethyl acetate/ethanol