反应详情

A mixture of 123d (152 mg, 0.26 mmol) and lithium hydroxide (61 mg, 2.56 mmol) in i-propanol/THF (1:1, 10 mL) and water (3 mL) was stirred at room temperature for 1 h. The mixture was evaporated under reduced pressure and the residue was extracted with ethyl acetate (2×10 mL). The combined ethyl acetate extract was concentrated under reduced pressure and the residue was purified by reverse-phase prep-HPLC to afford 123 (55 mg, 39%) as a yellow solid. MS-ESI: [M+H]+ 545.2. 1H NMR (500 MHz, DMSO-d6) δ 9.72 (s, 1H), 8.58 (d, J=5.0 Hz, 1H), 8.54 (d, J=2.5 Hz, 1H), 8.18 (s, 1H), 7.90 (d, J=2.0 Hz, 1H), 7.80-7.75 (m, 1H), 7.74 (s, 1H), 7.71 (d, J=5.0 Hz, 1H), 7.51 (s, 1H), 4.90 (t, J=5.0 Hz, 1H), 4.61-4.53 (m, 2H), 4.09 (q, J=7.5 Hz, 2H), 3.54 (s, 3H), 1.41 (s, 9H), 1.35 (t, J=6.0 Hz, 3H).

1. customThe mixture was evaporated under reduced pressure
2. extractionthe residue was extracted with ethyl acetate (2×10 mL)
3. extractionThe combined ethyl acetate extract
4. concentrationwas concentrated under reduced pressure
5. customthe residue was purified by reverse-phase prep-HPLC