反应详情

2-({4-[2-(Heptylamino)-2-oxoethyl]-1,3-thiazol-2-yl}thio)-2-methylpropionic acid tert-butyl ester (12.0 g) obtained in Example 303-1 was dissolved in tetrahydrofuran (120 mL), 1 M-borane/tetrahydrofuran complex (100 mL) was added under ice-cooling, and the mixture was stirred at room temperature for 12 hr. The reaction mixture was ice-cooled, and methanol (400 mL) was added dropwise. After warming to room temperature, the mixture was stirred for 1 hr. The reaction mixture was concentrated under reduced pressure, piperidine (120 mL) was added, and the mixture was stirred at 50° C. for 3 hr. The reaction mixture was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (elution solvent; dichloromethane:methanol=20:1 to 10:1) to give the title compound (5.5 g) as a slightly yellow oil.

1. addition1 M-borane/tetrahydrofuran complex (100 mL) was added under ice-
2. temperaturecooling
3. temperaturecooled
4. temperatureAfter warming to room temperature
5. stirringthe mixture was stirred for 1 hr
6. concentrationThe reaction mixture was concentrated under reduced pressure, piperidine (120 mL)
7. additionwas added
8. stirringthe mixture was stirred at 50° C. for 3 hr
9. concentrationThe reaction mixture was concentrated under reduced pressure
10. customthe residue was purified by silica gel chromatography (elution solvent; dichloromethane:methanol=20:1 to 10:1)