反应详情

To a solution of example 208 (0.070 g, 0.230 mmol) in ethanol (2 ml), sodium acetate (0.018 g, 0.230 mmol) and semicarbazide hydrochloride (0.026 g, 0.230 mmol) were added and stirred at RT for 12 h. The reaction mixture was concentrated and the residue was washed with bicarbonate solution, dichloromethane and dried under vacuum to afford the title compound as a yellow solid (0.040 g, 48%). M.P.: 249-250° C. 1H-NMR (δ ppm, DMSO-d6, 400 MHz): 9.70 (s, 1H), 8.88 (d, J=2.8 Hz, 1H), 8.54 (d, J=8.9 Hz, 1H), 8.45 (d, J=8.9 Hz, 1H), 8.37 (d, J=8.2 Hz, 1H), 8.01 (s, 1H), 7.99 (d, J=8.6 Hz, 1H), 7.81 (dd, J=8.6, 1.3 Hz, 1H), 7.53 (dd, J=8.2, 4.1 Hz, 1H), 6.78 (br s, 2H), 6.14 (s, 2H), 2.35 (s, 3H).

1. concentrationThe reaction mixture was concentrated
2. washthe residue was washed with bicarbonate solution, dichloromethane
3. customdried under vacuum