反应详情

Phosphoryl chloride (1.02 g.), 2-(2-formamidothiazol-4-yl)-2-(3-isoxazolylmethoxyimino)acetic acid (syn isomer, 1.0 g.), N,N-dimethylformamide (0.448 g.) and tetrahydrofuran (10 ml.) were treated in a similar manner to that of Example 5-(1) to give an activated acid solution. On the other hand, a mixture of 7-amino-3-cephem-4-carboxylic acid (0.91 g.), tetrahydrofuran (10 ml.) acetone (5 ml.) and water (5 ml.) was adjusted to pH 7.5 with 20% aqueous sodium carbonate at 0° to -5° C. The activated acid solution was added dropwise to the above solution at 0° to -5° C. while keeping at pH 7.5 to 8.0. The mixture was treated in a similar manner to that of Example 5-(1) to give 7-[2-(2-formamidothiazol-4-yl)-2-(3-isoxazolylmethoxyimino)acetamido]-3-cephem-4-carboxylic acid (syn isomer, 1.25 g.).

1. customto give an activated acid solution
2. additionThe activated acid solution was added dropwise to the above solution at 0° to -5° C.
3. additionThe mixture was treated in a similar manner to that of Example 5-(1)