反应详情

900 mg of the 3-(ethoxycarbonylmethyl)imidazo[5,1-b]-thiazole prepared in Preparation 50 was dissolved in 20 ml of methanol. To this solution was added 810 mg of sodium borohydride with ice-cooling, and the mixture was stirred at room temperature for 2.5 hours. To this was added 2 ml of concentrated hydrochloric acid, and the mixture was stirred at room temperature for 15 minutes. The solvent was distilled off under reduced pressure. To the residue was added 20 ml of water, and the pH of the mixture was adjusted to 7.5 by sodium hydrogencarbonate. The water was evaporated from the mixture under reduced pressure. To the residue were successively added 50 ml of dichloromethane and anhydrous magnesium sulfate. Insoluble matters were removed by filtration, and the solvent was distilled off under reduced pressure. The residue was washed with a mixture of 10 ml of ethyl acetate and 50 ml of ether to give 476 mg (yield 66%) of the title compound. NMR (CDCl3) d: 1.95 (1H, br-s), 3.01 (3H, t, J=6 Hz), 4.02 (1H, t, J=6 Hz), 6.57 (1H, s), 7.04 (1H, s), 7.90 (1H, s) MS (EI, CHCl3, 100° C.): 168 (M+)

1. temperaturecooling
2. stirringthe mixture was stirred at room temperature for 15 minutes
3. distillationThe solvent was distilled off under reduced pressure
4. additionTo the residue was added 20 ml of water
5. customThe water was evaporated from the mixture under reduced pressure
6. customInsoluble matters were removed by filtration
7. distillationthe solvent was distilled off under reduced pressure
8. washThe residue was washed with a mixture of 10 ml of ethyl acetate and 50 ml of ether