反应详情

To a solution of tert-butyl[(4′R)-6′-({[5-(difluoromethyl)pyrazin-2-yl]carbonyl}amino)-2′,2′-dimethyldispiro[cyclopropane-1,3′-chromene-4′,4″-[1,3]oxazol]-2″-yl]carbamate (373 mg, 0.704 mmol) in chloroform (6 ml) was added trifluoroacetic acid (2 ml). The mixture was stirred at room temperature for 2 hours and concentrated in vacuo. The residue was purified by silica gel column chromatography (precolumn: NH-silica gel, main column: neutral silica gel, chloroform/methanol=100:0-10:1). To the purified product was added a mixture of hexane and ethyl acetate (4:1), and the mixture was stirred at room temperature over night. The resulting precipitate was collected, washed with a mixture of hexane and ethyl acetate (4:1), and dried in vacuo to afford N-[(4′R)-2″-amino-2′,2′-dimethyldispiro[cyclopropane-1,3′-chromene-4′,4″-[1,3]oxazol]-6′-yl]-5-(difluoromethyl)pyrazine-2-carboxamide (253 mg).

1. concentrationconcentrated in vacuo
2. customThe residue was purified by silica gel column chromatography (precolumn: NH-silica gel, main column: neutral silica gel, chloroform/methanol=100:0-10:1)
3. additionTo the purified product was added
4. additiona mixture of hexane and ethyl acetate (4:1)
5. stirringthe mixture was stirred at room temperature over night
6. customThe resulting precipitate was collected
7. washwashed with a mixture of hexane and ethyl acetate (4:1)
8. customdried in vacuo