反应详情

The product from Example 23A (0.71 g, 2.28 mmol) in tetrahydrofuran (23 mL) and CH3OH (5.7 mL) was treated with 1N aqueous LiOH (5.7 mL, 5.7 mmol). After stirring overnight at room temperature, the organic solvents were removed under reduced pressure and the remaining aqueous solution was acidified to pH 1 with concentrated HCl. The acidified solution was extracted with ethyl acetate. The extracts were combined, dried over Na2SO4, filtered, and the filtrate concentrated under reduced pressure to provide the title compound as a solid. 1H NMR (300 MHz, DMSO-d6) δ 10.33 (s, 1H), 8.06 (m, 4H), 7.69 (m, 2H), 7.38 (m, 2H), 1.29 (s, 9H); MS (ESI+) m/z 298 (M+H)+.

1. customthe organic solvents were removed under reduced pressure
2. extractionThe acidified solution was extracted with ethyl acetate
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationthe filtrate concentrated under reduced pressure