反应详情

To 10 g. of 2,2,2-trichloroethyl 7β-amino-3-methyl-3-cephem-4-carboxylate hydrochloride was added about 70 ml. of water. About 2.5 g. of sodium bicarbonate was added thereto and, after stirring for a while, the resultant was extracted with ethyl acetate. The extract was dried over anhydrous sodium sulfate and concentrated at a temperature below 35° C. The so obtained free base was dissolved in 40 ml. of methanol and 5 g. of 4-hydroxy-3,5-di-tert.-butylbenzaldehyde was added thereto and stirring was continued at room temperature for 4 hours. The insolubles were dissolved by heating briefly and the reaction mixture was concentrated into a half amount thereof, which was then cooled to separate out crystalline substances. The substances were recovered by filtration and washed with cold methanol to give 2,2,2-trichloroethyl 7β-(4-hydroxy-3,5-di-tert.-butylbenzylideneamino)-3-methyl-3-cephem-4-carboxylate. Yield 7 g. The product was recrystallized from a small amount of methanol to give the pure product as slightly yellow colored crystals. m.p. 94° C.

1. extractionthe resultant was extracted with ethyl acetate
2. dry with materialThe extract was dried over anhydrous sodium sulfate
3. concentrationconcentrated at a temperature below 35° C
4. customThe so obtained free base
5. dissolutionwas dissolved in 40 ml
6. stirringstirring
7. dissolutionThe insolubles were dissolved
8. temperatureby heating briefly
9. concentrationthe reaction mixture was concentrated into a half amount
10. temperaturewhich was then cooled
11. customto separate out crystalline substances
12. filtrationThe substances were recovered by filtration
13. washwashed with cold methanol