反应详情

To a solution of compound 17c (826 mg, 1.61 mmol) in CH2Cl2 (5 mL) was added trifluoroacetic acid (1 mL) at room temperature. The mixture was stirred at room temperature for 18 h. The mixture was extracted with CH2Cl2, and H2O after basifying the water layer to pH˜8 with 1N aqueous NaOH. The organic solution was dried over Na2SO4 and concentrated. Purification of the residue by flash column chromatography (silica gel, 2% MeOH/EtOAc) gave Cpd 916 (675 mg). 1H NMR (400 MHz, CDCl3): δ 7.88 (d, J=3.3 Hz, 1H), 7.55 (d, J=3.3 Hz, 1H), 7.41 (s, 1H), 7.37 (d, J=8.03 Hz, 1H), 7.05 (d, J=8.3 Hz, 1H), 4.54 (br. s., 1H), 4.44 (br. s., 1H), 4.01-4.35 (m, 6H), 3.75-3.95 (m, 2H), 3.12-3.31 (m, 2H), 2.85 (t, J=5.8 Hz, 1H), 2.49 (br. s., 4H). MS m/z (M+H+) 412.0.

1. extractionThe mixture was extracted with CH2Cl2, and H2O
2. dry with materialThe organic solution was dried over Na2SO4
3. concentrationconcentrated
4. customPurification of the residue by flash column chromatography (silica gel, 2% MeOH/EtOAc)