反应详情

To a solution of Example 174 (305 mg, 0.657 mmol) in a mixture of THF (8 mL), water (8 mL), and EtOH (4 mL), was added LiOH (63 mg, 2.63 mmol). The reaction mixture was vigorously stirred for 24 hours, diluted with water (20 mL), and washed with Et2O (10 mL). The aqueous phase was then acidified to pH ˜1 using 1 N HCl, and then extracted with CH2Cl2 (4×50 mL). The combined organic layers were dried (Na2SO4), filtered, and concentrated under reduced pressure. The residue was then purified by silica gel flash chromatography (95:5 CH2Cl2/MeOH) to afford product (189 mg, 66%) as a white solid. (C26H29NO3S): LC-MS, RT 3.95 min., M+H 436.4; 1H NMR (CDCl3): δ 1.25 (s, 3H), 1.28 (s, 3H), 1.70-1.82 (m, 1H), 2.32-2.43 (m, 2H), 2.45 (s, 3H), 2.74-2.98 (m, 4H), 3.18 (t, 2H), 3.47-3.54 (m, 1H), 4.28 (t, 2H), 6.72 (dd, 1H), 6.78 (s, 1H), 7.08 (d, 1H), 7.51 (AB quartet, 4H).

1. washwashed with Et2O (10 mL)
2. extractionextracted with CH2Cl2 (4×50 mL)
3. dry with materialThe combined organic layers were dried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe residue was then purified by silica gel flash chromatography (95:5 CH2Cl2/MeOH)