反应详情

To a stirred solution of 26a (24 mg, 0.044 mmol) in CH2Cl2 (0.44 mL) was added trifluoroacetic acid (44 μL, 0.571 mmol). The mixture was stirred for 2 h at room temperature. The solvent was then evaporated and the residue was purified by silica gel column chromatography with gradient of MeOH (5-20%) in CH2Cl2. The residue was purified by prep-HPLC using an Aquasil C18 column with gradient of MeOH (5-95%) in water to afford 27a (7.7 mg, 39%) as a white solid. 1H NMR (DMSO-d6) δ(ppm): 9.41 (t, J=5.7 Hz, 1H), 8.69 (m, 1H), 8.28 (s, 1H), 7.41 (s, 1H), 7.33 (d, J=6.8 Hz, 2H), 7.28-7.24 (m, 3H), 7.05 (d, J=3.3 Hz, 1H), 6.86 (d, J=3.9 Hz, 1H), 4.44 (m, 2H), 4.40 (d, J=5.9 Hz, 2H), 3.44 (q, J=6.8 Hz, 1H), 1.20 (d, J=6.8 Hz, 3H). LRMS: calc 451.1; found 452.5 (MH)+.

1. customThe solvent was then evaporated
2. customthe residue was purified by silica gel column chromatography with gradient of MeOH (5-20%) in CH2Cl2
3. customThe residue was purified