反应详情

Potassium hydroxide (790 mg, 12.0 mmol) was dissolved in 3 ml of water, and 400 mg (2.40 mmol) of 5-fluoroisatin was added thereto. To this was added 600 mg (2.40 mmol) of compound s obtained in Reference Example 19 which was dissolved in dioxane-ethanol (2 ml-4 ml). The mixture was heat-refluxed for 6 days. The solvent was distilled off, and the residue was dissolved in water and washed with ether. The aqueous layer was filtered through Celite, and acetic acid was added to the flitrate. The precipitated crystals were collected by filtration. These crystals were then dried under reduced pressure, and recrystallized from dimethylformamide-water to obtain 460 mg of the above-mentioned compound (yield 48%).

1. customobtained in Reference Example 19 which
2. temperatureThe mixture was heat-refluxed for 6 days
3. distillationThe solvent was distilled off
4. dissolutionthe residue was dissolved in water
5. washwashed with ether
6. filtrationThe aqueous layer was filtered through Celite, and acetic acid
7. additionwas added to the flitrate
8. filtrationThe precipitated crystals were collected by filtration
9. customThese crystals were then dried under reduced pressure
10. customrecrystallized from dimethylformamide-water