反应详情

To 4 parts of 2-(2H-1,4-benzothiazin-3(4H)-ylidene)-2-(4-fluorophenyl)acetamide in 80 parts of DMF is added 6 parts dimethylformamide diethyl acetal and the reaction mixture was stirred at room temperature for 2 to 6 hours then heated at 80°-140° C. for 1 to 6 hours. After cooling 6 parts of methoxy-bis-(dimethylamino)methane is added and the reaction mixture then heated at 50° to 80° C. for 2 to 24 hrs. The cooled reaction mixture is then diluted with 40 parts of water and refluxed for 2 to 18 hr. Upon cooling the precipitate present was collected and recrystallized from aqueous DMF to give 4-(4-fluorophenyl)-5H-pyrido[3,4-b][1,4]benzothiazin-3(2H)-one which melts above 300°.

1. temperaturethen heated at 80°-140° C. for 1 to 6 hours
2. additionis added
3. temperaturethe reaction mixture then heated at 50° to 80° C. for 2 to 24 hrs
4. customThe cooled reaction mixture
5. temperaturerefluxed for 2 to 18 hr
6. temperatureUpon cooling the precipitate present
7. customwas collected
8. customrecrystallized from aqueous DMF