反应详情

温度

60 °C

The sodium salt of 3-acetoxymethyl-2-carboxy-7-[(5,6-dihydro-1,4-oxathiin-2-yl )acetamido]-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene (14 g.) is dissolved in distilled water (350 cc.). Sodium bicarbonate (2.69 g.) followed by 2-methyl-5-thioxo-1,3,4-thiadiazoline (4.65 g.) are added to the solution and the reaction mixture is heated with stirring at 60° C. for 6 hours. After cooling, the reaction mixture is washed with ethyl acetate (2 × 150 cc.) and then acidified to pH 2 by addition of 4N hydrochloric acid in the presence of ethyl acetate (350 cc.). After decanting the organic phase, the aqueous phase is extracted twice with ethyl acetate (total 150 cc.). The organic extracts are combined, washed six times with water (total 600 cc.), dried over sodium sulphate, treated with decolourizing charcoal, filtered and then concentrated under reduced pressure (20 mm.Hg) to a final volume of 80 cc. After 30 minutes at 2° C., the solid compound which has formed is filtered off and then washed twice with ethyl acetate (10 cc.) and finally with diisopropyl ether (100 cc.). After drying under reduced pressure (0.5 mm.Hg), 2-carboxy-7-[(5,6-dihydro-1,4-oxathiin-2-yl )acetamido]-3-[(5-methyl-1,3,4-thiadiazol-2-yl )thiomethyl]-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene (7.5 g.) is obtained.

1. additionare added to the solution
2. temperaturethe reaction mixture is heated
3. temperatureAfter cooling
4. washthe reaction mixture is washed with ethyl acetate (2 × 150 cc.)
5. additionacidified to pH 2 by addition of 4N hydrochloric acid in the presence of ethyl acetate (350 cc.)
6. customAfter decanting the organic phase
7. extractionthe aqueous phase is extracted twice with ethyl acetate (total 150 cc.)
8. washwashed six times with water (total 600 cc.)
9. dry with materialdried over sodium sulphate
10. additiontreated with decolourizing charcoal
11. filtrationfiltered
12. concentrationconcentrated under reduced pressure (20 mm.Hg) to a final volume of 80 cc
13. waitAfter 30 minutes at 2° C.
14. customthe solid compound which has formed
15. filtrationis filtered off
16. washwashed twice with ethyl acetate (10 cc.) and finally with diisopropyl ether (100 cc.)
17. customAfter drying under reduced pressure (0.5 mm.Hg)