反应详情

In 250 ml of water-dioxane (1:1) was suspended 10 g of 2-(2,5-dioxopyrrolidin-3-yl)glycine and under cooling at 0°-5° C. the above amino acid was dissolved by addition of 70 ml of 1 N sodium hydroxide. To this solution was added 15 ml of benzyloxycarbonyl chloride and, with adjusting pH to 7.1-7.4 with sodium hydrogen carbonate, the mixture was stirred at the same temperature as above for 2 hours. The reaction mixture was concentrated under reduced pressure to remove the organic solvent and the concentrate was washed with ethyl acetate. The aqueous layer was adjusted to pH 1 with conc. hydrochloric acid and allowed to stand in a refrigerator overnight to give crystals. Yield 15.8 g.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. customto remove the organic solvent
3. washthe concentrate was washed with ethyl acetate
4. customto stand in a refrigerator overnight
5. customto give crystals