反应详情

To an ethanol (60.0 mL) solution of ethyl 6-bromo-3-[2,6-dimethoxy-4-(methoxymethyl)phenyl]pyrazolo[5,1-b][1,3]thiazole-7-carboxylate (3.84 g, 8.45 mmol) was added a 5N aqueous solution of sodium hydroxide (5.07 mL, 25.3 mmol) and heated to reflux for two hours. After the reaction was completed, the solvent was distilled off under reduced pressure, water (30 mL) was added to the residue, a 5N aqueous solution of hydrochloric acid was added while cooling on ice so that the solution became acidic, and the precipitated solid was subjected to suction filtration and dried to obtain the title compound (3.4 g, 7.96 mmol).

1. temperatureheated
2. temperatureto reflux for two hours
3. distillationthe solvent was distilled off under reduced pressure, water (30 mL)
4. additionwas added to the residue
5. additiona 5N aqueous solution of hydrochloric acid was added
6. temperaturewhile cooling on ice so that the solution
7. filtrationthe precipitated solid was subjected to suction filtration
8. customdried