反应详情

温度

60 °C

3-Acetoxymethyl-2-carboxy-8-oxo-7-[(1,3-dithiol-2-on-4-yl)-acetamido]-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene (8.8 g.) is dissolved in distilled water (100 cc.) and sodium bicarbonate (1.72 g.). A solution of 2-methyl-5-thioxo-1,3,4-thiadiazoline (2.7 g.) in distilled water (100 cc.) and sodium bicarbonate (1.72 g.) is added and the resulting solution is heated to 60° C. for 6 hours. After cooling, it is acidified to pH= 5.5 by adding 4 N hydrochloric acid and the extracted twice with ethyl acetate (100 cc.). The organic extracts are discarded. The acidification is continued in the presence of ethyl acetate (200 cc.) until the pH is 2. After decanting the organic phase, the aqueous phase is extracted twice with ethyl acetate (a total of 200 cc.). The organic extracts are washed twice with water (200 cc.), dried over magnesium sulphate, treated with decolourising charcoal and then filtered and concentrated under reduced pressure (20 mm.Hg) to a final volume of 25 cc. The solid compound formed is removed by filtration and washed twice with isopropyl ether (25 cc.). After drying under reduced pressure (0.5 mm.Hg), 2-carboxy-3-[(5-methyl-1,3,4-thiadiazol-2-yl)-thiomethyl]-8-oxo-7-[(1,3-dithiol-2-on-4-yl)-acetamido]-5-thia-1-azabicyclo[4.2.0]oct-2-ene (5.5 g.) is obtained.

1. temperatureAfter cooling
2. extractionthe extracted twice with ethyl acetate (100 cc.)
3. customAfter decanting the organic phase
4. extractionthe aqueous phase is extracted twice with ethyl acetate (a total of 200 cc
5. washThe organic extracts are washed twice with water (200 cc.)
6. dry with materialdried over magnesium sulphate
7. additiontreated with decolourising charcoal
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure (20 mm.Hg) to a final volume of 25 cc
10. customThe solid compound formed
11. customis removed by filtration
12. washwashed twice with isopropyl ether (25 cc.)
13. customAfter drying under reduced pressure (0.5 mm.Hg)