反应详情

1.7 g of ethyl (Z)-2-(2-acetamidothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetate are suspended in 17 ml of methanol, and 5 ml of 2N sodium hydroxide are added thereto. The mixture is refluxed for 30 minutes with heating. Then, the mixture is concentrated under reduced pressure to remove methanol. The residue is adjusted to pH 2 with diluted hydrochloric acid, and the aqueous mixture is extracted with a mixture of ethyl acetate and tetrahydrofuran (2:1). The extract is dried and concentrated under reduced pressure to dryness. The residue is crystallized with isopropanol, and the crystals are collected by filtration and then recrystallized from water. 0.8 g of (Z)-2-(2-acetamidothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetic acid is obtained.

1. temperatureThe mixture is refluxed for 30 minutes
2. temperaturewith heating
3. concentrationThen, the mixture is concentrated under reduced pressure
4. customto remove methanol
5. extractionthe aqueous mixture is extracted with a mixture of ethyl acetate and tetrahydrofuran (2:1)
6. customThe extract is dried
7. concentrationconcentrated under reduced pressure to dryness
8. customThe residue is crystallized with isopropanol
9. filtrationthe crystals are collected by filtration
10. customrecrystallized from water