反应详情

A 1 L round-bottomed flask was charged with compound 7.4 (40.9 g, 85.8 mmol), THF (100 mL) and MeOH (100 mL). Next, 2 N NaOH (86 mL, 172 mmol) was added dropwise, and the reaction was stirred at room temperature for 1 h. The solution was neutralized with 2 N HCl (86 mL) and the organic solvent was evaporated to give an aqueous solution and an insoluble oil. The residue was diluted with AcOEt (300 mL) and 1N HCl (300 mL), and partitioned. The organic phase was successively washed with water (400 mL) and brine (400 mL), dried over MgSO4, and concentrated to give white crystals. Recrystallization from 520 mL of AcOEt/hexane (3/10) gave compound 7 (33.4 g) as white crystals. MS APSI m/e: 447 (M−H). 1H NMR (400 MHz) (DMSO-d6) δ 13.0 (1H, brs); 7.64 (2H, d, J=8.8 Hz); 7.38 (2H, d, J=8.3 Hz); 7.30-7.20 (2H, m); 7.16 (4H, d, J=8.3 Hz); 6.89 (1H, d, J=8.5 Hz); 5.14 (2H, s); 4.74 (2H, s); 2.19 (3H, s).

1. customthe organic solvent was evaporated
2. customto give an aqueous solution
3. custompartitioned
4. washThe organic phase was successively washed with water (400 mL) and brine (400 mL)
5. dry with materialdried over MgSO4
6. concentrationconcentrated
7. customto give white crystals
8. customRecrystallization from 520 mL of AcOEt/hexane (3/10)