反应详情

A mixture of 7β-[2-cyclopropyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]-3-carbamoyloxymethyl-3-cephem-4-carboxylic acid (syn isomer) (2.0 g) and concentrated hydrochloric acid (1.2 ml) in a mixture of methanol (15 ml) and tetrahydrofuran (15 ml) was warmed at 33° to 35° C. for 1.5 hours. The mixture was poured into ice-water, adjusted to pH 7.5 with saturated aqueous solution of sodium bicarbonate and washed with ethyl acetate. The aqueous solution was adjusted to pH 2 with 1N hydrochloric acid and extracted with a mixture of ethyl acetate and tetrahydrofuran. The extract was washed with saturated aqueous solution of sodium chloride, dried over magnesium sulfate and concentrated in vacuo. The residue was triturated with ethyl acetate to give 7β-[2-(2-aminothiazol-4-yl)-2-(cyclopropyloxyimino)acetamido]-3-carbamoyloxymethyl-3-cephem-4-carboxylic acid (syn isomer) (0.86 g).

1. temperaturewas warmed at 33° to 35° C. for 1.5 hours
2. washwashed with ethyl acetate
3. extractionextracted with a mixture of ethyl acetate and tetrahydrofuran
4. washThe extract was washed with saturated aqueous solution of sodium chloride
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue was triturated with ethyl acetate