反应详情

262 mg (2.0 mmol) of D-Hyp-OH was dissolved in 5 ml of a saturated aqueous solution of sodium hydrogencarbonate under stirring and a mixture of 742 mg (2.2 mmol) of Fmoc-OSu and 10 ml of 1,4-dioxane was added dropwise under cooling with ice; thereafter, and the mixture was stirred at room temperature for 3 days. In the meantime, a saturated aqueous solution of sodium hydrogencarbonate was added as appropriate to keep the pH of the reaction mixture at 8-9. After being rendered acidic with hydrochloric acid under cooling with ice, the reaction mixture was subjected to extraction with ethyl acetate. The ethyl acetate layer was washed with water and saturated brine, dried with anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography (eluting solvents were chloroform and acetic acid supplemented chloroform:methanol=10:1); to remove the acetic acid used in eluting, the fractions were once concentrated under reduced pressure and dissolved again in ethyl acetate; thereafter, the solution was washed with water, dried with anhydrous magnesium sulfate and concentrated under reduced pressure to give a colorless powder in the amount of 660 mg (93%).

1. additionwas added dropwise
2. temperatureunder cooling with ice
3. stirringthereafter, and the mixture was stirred at room temperature for 3 days
4. temperatureunder cooling with ice
5. extractionthe reaction mixture was subjected to extraction with ethyl acetate
6. washThe ethyl acetate layer was washed with water and saturated brine
7. dry with materialdried with anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe resulting crude product was purified by silica gel column chromatography (eluting solvents were chloroform and acetic acid supplemented chloroform:methanol=10:1)
10. customto remove the acetic acid
11. washin eluting
12. concentrationthe fractions were once concentrated under reduced pressure
13. dissolutiondissolved again in ethyl acetate
14. washthereafter, the solution was washed with water
15. dry with materialdried with anhydrous magnesium sulfate
16. concentrationconcentrated under reduced pressure
17. customto give a colorless powder in the amount of 660 mg (93%)