反应详情

To 8 ml of 1 N sodium hydroxide-dioxane (1:1) mixture was added 700 mg of the compound of Example 20. After the mixture had been stirred at room temperature for 2 hours, it was acidified with 1 N hydrochloric acid. The mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with water dried, and concentrated. The resulting crude product was recrystallized from ethyl acetate-isopropyl ether to give 620 mg of 2-[4-(4-bromo-2-fluorophenylmethyl)-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl]acetic acid. The structural formula and physical data of this compound are shown in Table 36.

1. extractionThe mixture was extracted with ethyl acetate
2. washThe ethyl acetate layer was washed with water
3. customdried
4. concentrationconcentrated
5. customThe resulting crude product was recrystallized from ethyl acetate-isopropyl ether