反应详情

To a mixture of benzhydryl 7-[2-(2-tritylaminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(4-methyl-5-oxo-6-hydroxy-4,5-dihydro-1,2,4-triazin-3-yl)thiomethyl-3-cephem-4-carboxylate (syn isomer) (1.20 g) and anisole (2.5 ml) in methylene chloride (2.5 ml) was added trifluoroacetic acid (5 ml) under ice-cooling. After being stirred for 30 minutes, the mixture was poured into diisopropyl ether (50 ml). The resultant mixture was adjusted to pH 7 with an aqueous solution of sodium bicarbonate. The separated aqueous layer was washed with ethyl acetate, acidified with 6N hydrochloric acid and extracted with a mixture of tetrahydrofuran and ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride, dried and evaporated under reduced pressure. The residue was triturated in diethyl ether and collected by filtration to give 7-[2-(2-aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(4-methyl-5-oxo-6-hydroxy-4,5-dihydro-1,2,4-triazin-3-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (600 mg).

1. temperaturecooling
2. washThe separated aqueous layer was washed with ethyl acetate
3. extractionextracted with a mixture of tetrahydrofuran and ethyl acetate
4. washThe extract was washed with a saturated aqueous solution of sodium chloride
5. customdried
6. customevaporated under reduced pressure
7. customThe residue was triturated in diethyl ether
8. filtrationcollected by filtration