反应详情

1.60 g of 4-dimethylamino-pyridine were added to a suspension of 4.5 g of the product of Step A in 90 ml of tetrahydrofuran and the mixture was refluxed for four hours and was evaporated to dryness under reduced pressure. The residue was added to 90 ml of water and the mixture was stirred for 30 minutes and was vacuum filtered. The product was washed with water and dried under reduced pressure at 70° C. to obtain 4.50 g of 1,3-dihydro-3-methyl-1-[(2-pyridinyl)-imino]-5-trifluoromethyl-furo[3,4-b]quinoline-9-ol which was crystallized from absolute ethanol.

1. temperaturethe mixture was refluxed for four hours
2. customwas evaporated to dryness under reduced pressure
3. additionThe residue was added to 90 ml of water
4. filtrationfiltered
5. washThe product was washed with water
6. customdried under reduced pressure at 70° C.