反应详情

30.0 g of the crystals obtained in Example 4 was dissolved in 600 ml of methanol, and after the addition of 65 ml of 10% sodium hydroxide, the mixture was stirred at a room temperature for 20 hours, and 1000 ml of water was added. The reaction mixture was adjusted to pH 4 with concentrated hydrochloric acid, and extracted twice with 800 ml of chloroform. The extract was dried over magnesium sulfate and concentrated under a reduced pressure to crystallize the title compound, which was then filtered and washed with hexane to obtain 25.2 g of colorless crystals.

1. extractionextracted twice with 800 ml of chloroform
2. dry with materialThe extract was dried over magnesium sulfate
3. concentrationconcentrated under a reduced pressure
4. customto crystallize the title compound, which
5. filtrationwas then filtered
6. washwashed with hexane