反应详情

(2S,5R)—N-(2-Benzyloxycarbonylaminoethoxy)-5-(benzyloxyamino)-1-(tert-butoxycarbonyl)piperidine-2-carboxamide (2.91 g, 5.362 mmol) was dissolved in 1,4-dioxane (5 mL), to which was added under ice cooling 4M hydrochloric acid-dioxane solution (10 mL). After stirring for 2 h., the mixture was concentrated under reduced pressure, dissolved in water (30 mL), and washed with ether. The aqueous layer was ice-cooled, and pH was set to ca. pH 7 with 5M sodium hydroxide and acetic acid, and then extracted with ethyl acetate. The organic layer was washed with saturated brine, and dried over anhydrous sodium sulfate, and then the solvent was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (chloroform chloroform/methanol=3:1) to afford 2.27 g of the title compound (yield 95%).

1. additionwas added under ice cooling 4M hydrochloric acid-dioxane solution (10 mL)
2. concentrationthe mixture was concentrated under reduced pressure
3. dissolutiondissolved in water (30 mL)
4. washwashed with ether
5. temperaturecooled
6. extractionextracted with ethyl acetate
7. washThe organic layer was washed with saturated brine
8. dry with materialdried over anhydrous sodium sulfate
9. concentrationthe solvent was concentrated under reduced pressure