反应详情

The product of Example 3C (76 mg, 0.21 mmol) in 2 mL tetrahydrofuran was stirred with acetic anhydride (0.026 mL, 0.275 mmol) and triethylamine (0.088 mL, 0.63 mmol) at rt for 3 h. The reaction mixture was then diluted with ethyl acetate and washed with water and brine. The organic phase was dried over Na2SO4, filtered and concentrated. The residue was chromatographed on silica gel, eluting with 35% ethyl acetate-hexane and then 60% ethyl acetate-hexane to afford the title compound as a tan foam (38 mg, 45%). 1H NMR (DMSO-d6) δ 8.03 (s, 1H), 7.48 (m, 4H), 7.10 (m, 2H), 6.82 (m, 1H), 4.72 (d, J=3.8 Hz, 1H), 3.92 (m, 1H), 2.84-3.02 (m, 3H), 2.73 (s, 3H), 2.44 (m, 1H), 1.86 (m, 1H), 1.61 (m, 1H), 1.27 (s, 9H); MS (ESI+) m/z 405 (M+H)+.

1. washwashed with water and brine
2. dry with materialThe organic phase was dried over Na2SO4
3. filtrationfiltered
4. concentrationconcentrated
5. customThe residue was chromatographed on silica gel
6. washeluting with 35% ethyl acetate-hexane