反应详情

50 g of commercially available cephradine hydrate were suspended in a mixture of water and conc. hydrochloric acid (180/7) at 5° to 10° C. with stirring. The pH was brought to 1.6 to 2.0 with hydrochloric acid in order to form a complete solution and 16 g of dimethylformamide were added. The solution was filtered and the residue was washed with 35 ml of water. The combined filtrate was warmed to 35° to 40° and the pH brought to 2.8 with aqueous triethylamine. Stirring was continued for several minutes and the pH was finally adjusted to about 4.9 with aqueous triethylamine. The resulting slurry was cooled to room temperature and filtered. The residue was washed with 80% (v/v) acetone and dried to obtain the heading compound, m.p. 190° to 200° C. (decomp.).

1. additionwere added
2. filtrationThe solution was filtered
3. washthe residue was washed with 35 ml of water
4. temperatureThe combined filtrate was warmed to 35° to 40°
5. stirringStirring
6. waitwas continued for several minutes
7. filtrationfiltered
8. washThe residue was washed with 80% (v/v) acetone
9. customdried
10. customto obtain the heading compound, m.p. 190° to 200° C. (decomp.)