反应详情

To a suspension of benzhydryl 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylate (syn isomer)(2.3 g) in methylene chloride (40 ml) were added anisole (3.3 g) and trifluoroacetic acid (8.7 g) under ice-cooling with stirring, and the stirring was continued at ambient temperature for 75 minutes. After evaporation of the reaction mixture, to the residue were added water and ethyl acetate, followed by adjusting to pH 7 with a saturated aqueous solution of sodium bicarbonate. To the separated aqueous solution was added ethyl acetate, followed by adjusting to pH 2 with 10% hydrochloric acid. The ethyl acetate layer was separated out, washed with an aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate and then evaporated to dryness to give a residue, which was washed with diethyl ether to obtain 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid (syn isomer)(1.45 g).

1. temperaturecooling
2. customAfter evaporation of the reaction mixture
3. additionto the residue were added water and ethyl acetate
4. additionTo the separated aqueous solution was added ethyl acetate
5. customThe ethyl acetate layer was separated out
6. washwashed with an aqueous solution of sodium chloride
7. dry with materialdried over anhydrous magnesium sulfate
8. customevaporated to dryness
9. customto give a residue, which
10. washwas washed with diethyl ether