反应详情

In 300 ml of methanol was dissolved 2 g of benzyloxycarbonyl-2-(2,5-dioxopyrrolidin-3-yl)glycine and under ice-cooling an excess of an ethereal solution of diazomethane was added. The mixture was stirred under ice-cooling for 2 hours and then concentrated under reduced pressure. The concentrate was chromatographed on a silica gel column and eluted with toluene-acetone (4:1). The eluate was concentrated under reduced pressure and after addition of ethyl ether to the residue, the mixture was allowed to stand in a refrigerator overnight to give crystals. Yield 1.3 g.

1. additionwas added
2. temperaturecooling for 2 hours
3. concentrationconcentrated under reduced pressure
4. customThe concentrate was chromatographed on a silica gel column
5. washeluted with toluene-acetone (4:1)
6. concentrationThe eluate was concentrated under reduced pressure
7. additionafter addition of ethyl ether to the residue
8. customto stand in a refrigerator overnight
9. customto give crystals