反应详情

To a mixture of anisole (2 ml) and trifluoroacetic acid (6 ml) was added 7-[2-(2-amino-5-chlorothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer) (1.7 g) at 20° to 25° C. with stirring. The reaction mixture was stirred for an hour at the same temperature. The resultant solution was poured into a mixed solvent of dissopropyl ether (300 ml) and petroleum ether (100 ml). The precipitates were collected by filtration, washed with petroleum ether, and were dissolved in an aqueous solution of sodium bicarbonate at pH 7.5. The aqueous solution was washed with ethyl acetate, adjusted to pH 2.8 with a diluted hydrochloric acid, and extracted with a mixed solvent of ethyl acetate and tetrahydrofuran. The organic layer was washed with a saturated aqueous solution of sodium chloride and dried over magnesium sulfate. After removing the solvent in vacuo, diisopropyl ether was added to the residue. The insoluble precipitates were collected by filtration to give 7-[2-(2-amino-5-chlorothiazol-4-yl)-2-carboxymethoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer)(1.2 g), mp 165° to 167° C. (dec.).

1. stirringThe reaction mixture was stirred for an hour at the same temperature
2. filtrationThe precipitates were collected by filtration
3. washwashed with petroleum ether
4. dissolutionwere dissolved in an aqueous solution of sodium bicarbonate at pH 7.5
5. washThe aqueous solution was washed with ethyl acetate
6. extractionextracted with a mixed solvent of ethyl acetate and tetrahydrofuran
7. washThe organic layer was washed with a saturated aqueous solution of sodium chloride
8. dry with materialdried over magnesium sulfate
9. customAfter removing the solvent in vacuo, diisopropyl ether
10. additionwas added to the residue
11. customThe insoluble precipitates
12. filtrationwere collected by filtration