反应详情

To a solution of 2-benzyloxycarbonylamino-2-methylpropionic acid (2.37 g) in tetrahydrofuran (20 mL) was added 1,1′-carbonylbis-1H-imidazole (1.78 g), and the mixture was stirred at room temperature for 1 hour. To the reaction mixture was added 1-methylpiperazine (2.0 mL), and the mixture was stirred at 40° C. for 3.5 days. To the reaction mixture was added methanol, and the resulting mixture was concentrated under reduced pressure. The residue was purified by column chromatography on silica gel (eluent: dichloromethane/methanol=20/1) to give 1-(2-benzyloxycarbonylamino-2-methylpropionyl)-4-methylpiperazine (1.99 g). This material was dissolved in methanol (10 mL). To the solution was added 10% palladium-carbon powder (0.4 g), and the mixture was stirred at room temperature under a hydrogen atmosphere for 3 hours. The insoluble material was removed by filtration, and the solvent of the filtrate was removed under reduced pressure to give the title compound (1.14 g).

1. stirringthe mixture was stirred at 40° C. for 3.5 days
2. concentrationthe resulting mixture was concentrated under reduced pressure
3. customThe residue was purified by column chromatography on silica gel (eluent: dichloromethane/methanol=20/1)