反应详情

A mixture of 7-[2-(2-formamidothiazol-4-yl)-2-(2-ethoxyethoxyimino)acetamido]-3-cephem-4-carboxylic acid (syn isomer, 2.2 g.), conc hydrochloric acid (2 ml.) and methanol (30 ml.) was stirred at room temperature for 1.6 hours. After concentrating the resultant solution in vacuo, water was added to the residue, adjusted to pH 6.5 with sodium bicarbonate and washed with ethyl acetate. The aqueous solution was treated with activated charcoal and adjusted to pH 3.0 with conc. hydrochloric acid. The precipitates were collected by filtration, washed with water and dried over phosphorus pentoxide under reduced pressure to give 7-[2-(2-aminothiazol-4-yl)-2-(2-ethoxyethoxyimino)acetamido]-3-cephem-4-carboxylic acid (syn isomer, 0.87 g.).

1. concentrationAfter concentrating the resultant solution in vacuo, water
2. additionwas added to the residue
3. washwashed with ethyl acetate
4. additionThe aqueous solution was treated with activated charcoal
5. filtrationThe precipitates were collected by filtration
6. washwashed with water
7. dry with materialdried over phosphorus pentoxide under reduced pressure