反应详情

40 g of 7-amino-3-vinyl-3-cephem-4-carboxylic acid in 400 ml of dichloromethane are treated with 55.7 ml of N,O-bistnmethyl-silylacetamid. The mixture obtained is stirred for ca. 2 hours at room temperature, cooled to 0° and treated with 52.2 g of 2-(Z)-(2-aminothiazol-4-yl) -2-acetoxyiminoacetic acid chloride in the form of a hydrochloride in small portions. The mixture obtained is stirred for ca.90 minutes at 0° and added under stirring to a mixture of 44.55 g of NaHCO3, 600 ml of water und 100 ml of dichloromethane of a temperature of 5°. The pH of the mixture obtained is adjusted to a pH of ca. 7.2-7.3 with a saturated aqueous solution of NaHCO3. The phases formed are separated. To the aqueous phase 300 ml of water are added and 28.7 g of NH4Cl. The pH of the mixture obtained is adjusted to pH 8 by addition of an aqueous 10% K2CO3 solution and the mixture is stirred for ca. 80 minutes. A solution is obtained. The pH of the solution obtained is adjusted to pH 3 by addition of 5 m sulphuric acid. 7-(Z)-[2-(2-amino-thiazol4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid precipitates, is filtrated off, washed with water and dried. 7-(Z)-[2-(2-amino-thiazol-4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid in a purity of 94.3 % is obtained.

1. customThe mixture obtained
2. temperaturecooled to 0°
3. customThe mixture obtained
4. stirringis stirred for ca
5. addition90 minutes at 0° and added
6. customThe pH of the mixture obtained
7. customThe phases formed
8. customare separated
9. additionTo the aqueous phase 300 ml of water are added
10. customThe pH of the mixture obtained
11. stirringthe mixture is stirred for ca. 80 minutes
12. customA solution is obtained
13. customThe pH of the solution obtained
14. custom7-(Z)-[2-(2-amino-thiazol4-yl)-2-hydroxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid precipitates
15. filtrationis filtrated off
16. washwashed with water
17. customdried