反应详情

To a solution of 2-(4-acetoxymethyl-2-furoyl)-6-chloro-1-ethoxycarbonyl-3-[(S)-2-acetoxypropionylamino]indole (step 1, 267 mg, 0.494 mmol) in ethanol (2 ml) was added 2N aqueous sodium hydroxide (2 ml). After stirrig for 3 h, the mixture was poured into saturated aqueous ammonium chloride (20 ml) and extracted with ethyl acetate (80 ml). The organic layer was washed with brine (20 ml), dried (MgSO4) and concentrated. The residue was purified by flash column chromatography eluting with dichloromethane/methanol (50/1) and recrystallized from 2-propanol/isopropyl ether to give 43 mg (24%) of the titled compound as yellow solids. m.p.: 213-214° C. 1H-NMR (CDCl3) δ: 11.4 (1H, br s), 10.8 (1H, br s), 8.35 (1H, d, J=8.90 Hz), 7.76 (1H, s), 7.53 (1H, d, J=1.81 Hz), 7.45 (1H, s), 7.01 (1H, dd, J=8.90 Hz, 1.81 Hz), 4.58 (2H, d, J=5.11 Hz), 4.36 (1H, q, J=6.92 Hz), 1.52 (3H, d, J=6.92 Hz).

1. extractionextracted with ethyl acetate (80 ml)
2. washThe organic layer was washed with brine (20 ml)
3. dry with materialdried (MgSO4)
4. concentrationconcentrated
5. customThe residue was purified by flash column chromatography
6. washeluting with dichloromethane/methanol (50/1)
7. customrecrystallized from 2-propanol/isopropyl ether