反应详情

3 g (8.85 mmol) of the compound obtained in Example 23 was stirred in 30 ml of aqueous 80% ethanol solution and 10 ml of aqueous 30% sulfuric acid solution at 120° C. for 18 hours. After the reaction was completed, the mixture was cooled to room temperature, and neutralized with conc. ammonia water. Then the obtained solid was filtered, washed with water, and dried to give 1.8 g of the title compound in a yield of 68%.

1. filtrationThen the obtained solid was filtered
2. washwashed with water
3. customdried