反应详情

A solution of compound 112 (300 mg, 0.6 mmol) in dichloromethane (10 mL) was added BCl3 (3 mL, 3 mmol, 1M in dichloromethane) at −78° C. The resulting solution was kept at −20° C. for 1 hour, then quenched by the addition of methanol (10 mL). Volatiles were distilled out under vacuum to give a residue, which was dissolved into methanol (5 mL) and neutralized by Con. NH4OH (2 ml, 26% aqueous solution). After concentration, the crude product was purified by a silica gel column, eluted with 10% methanol in dichloromethane to give the title compound as a white solid (94.2 mg, 49%). (ES, m/z): [M+H]+ 300.9; 1H NMR (D2O, 300 MHz) δ 6.16 (d, J=6.3 Hz, 1H), 4.11-4.15 (m, 1H), 3.93-3.97 (m, 1H), 3.77-3.83 (m, 1H), 3.44-3.48 (m, 1H), 2.91 (s, 6H), 2.52-2.68 (m, 1H), 2.37-2.49 (m, 1H).

1. customquenched by the addition of methanol (10 mL)
2. distillationVolatiles were distilled out under vacuum
3. customto give a residue, which
4. concentrationAfter concentration
5. customthe crude product was purified by a silica gel column
6. washeluted with 10% methanol in dichloromethane