反应详情

温度

140 °C

5-methyl-6-[1-(2,2,2-trichloroethoxycarbonyl)-1,4-dihydro-4-pyridazinyl]-2H-1,4-thiazin-3(4H)-one (2.4 g) was well mixed with sulfur sublimed (10.7 g) in a mortar and the mixture was stirred at 140° C. for 1.5 hours and then was cooled to ambient temperature. The obtained solid was ground and was extracted with methanol. Methanol was removed under reduced pressure. The residue was dissolved in 50 ml of 2N hydrochloric acid. The insoluble matter was removed by filtration and the filtrate was adjusted to pH 7.2 by 2N aqueous sodium hydroxide. The resulting precipitates were removed by filtration. The filtrate was extracted with chloroform (20 ml×5 times) and the extract was evaporated to dryness. After combined with the above solid, the residue was recrystallized from methanol to give the titled compound (0.3 g, yield 23%) as pale yellow plates.

1. temperaturewas cooled to ambient temperature
2. extractionwas extracted with methanol
3. customMethanol was removed under reduced pressure
4. dissolutionThe residue was dissolved in 50 ml of 2N hydrochloric acid
5. customThe insoluble matter was removed by filtration
6. customThe resulting precipitates
7. customwere removed by filtration
8. extractionThe filtrate was extracted with chloroform (20 ml×5 times)
9. customthe extract was evaporated to dryness
10. customthe residue was recrystallized from methanol