反应详情

A 4.0 N hydrogen chloride/dioxane solution (14 ml) is added to t-butyl (2S)-2-[3-[2-(acetylthio)ethyl]-3-(2-cyclohexylethyl)ureido]propionate (Compound No. 5-1, 2.3 g), and the mixture is stirred at room temperature overnight. The reaction mixture is concentrated under reduced pressure, to the resulting oily matter are added a 5% aqueous sodium hydrogencarbonate solution (30 ml) and ethyl acetate (30 ml), and the aqueous layer is separated from the organic layer. A 5% aqueous citric acid solution is added to the aqueous layer to acidify it, and the whole is extracted with ethyl acetate. The organic layer is washed with water and saturated brine successively, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting oily matter is purified by silica gel column chromatography to give 826 mg (42%) of the titled compound (Compound No. 7-1) as crystals.

1. concentrationThe reaction mixture is concentrated under reduced pressure, to the resulting oily matter
2. additionare added a 5% aqueous sodium hydrogencarbonate solution (30 ml) and ethyl acetate (30 ml)
3. customthe aqueous layer is separated from the organic layer
4. additionA 5% aqueous citric acid solution is added to the aqueous layer
5. extractionthe whole is extracted with ethyl acetate
6. washThe organic layer is washed with water and saturated brine successively
7. dry with materialdried over anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe resulting oily matter is purified by silica gel column chromatography