反应详情

Methanol (15 ml) and conc. hydrochloric acid (0.8 g) were added to 7-[2-(tert-butoxycarbonylmethoxyimino)-2-(2-formamidothiazol-4-yl)acetamido]-3-chloro-3-cephem-4-carboxylic acid (syn isomer, 2.2 g), and stirred at room temperature for 2.5 hours. To the resultant solution were added ethyl acetate (50 ml) and water (50 ml), and then the solution was adjusted to pH 7.5 with a saturated solution of sodium bicarbonate. After separating the aqueous layer, the aqueous solution was saturated with sodium chloride, and adjusted to pH 3.0 with 10% hydrochloric acid. After adding water, the solution was extracted with ethyl acetate. The extract was washed with a saturated solution of sodium chloride, dried over magnesium sulfate and concentrated in vacuo. The residue was triturated with diisopropyl ether and the precipitates were collected by filtration and dried to give 7-[2-(tert-butoxycarbonylmethoxyimino)-2-(2-aminothiazol-4-yl)acetamido]-3-chloro-3-cephem-4-carboxylic acid (syn isomer, 1.72 g).

1. customAfter separating the aqueous layer
2. additionAfter adding water
3. extractionthe solution was extracted with ethyl acetate
4. washThe extract was washed with a saturated solution of sodium chloride
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was triturated with diisopropyl ether
8. filtrationthe precipitates were collected by filtration
9. customdried