反应详情

温度

-5 °C

Dimethylformamide (0.34 g.) was added to dry ethyl acetate (1 ml.), and then phosphorus oxychloride (0.72 g.) was added thereto under 10° C. The mixture was stirred at -5° C. to solidify. Dry ethyl acetate (10 ml.) was added thereto and 2-methoxyimino-2-(1,2,3-thiadiazol-4-yl)acetic acid (syn isomer) (0.8 g.) was added to the mixture at 0° C., after which the resulting mixture was stirred for 30 minutes at the same temperature. On the other hand, trimethylsilylacetamide (4.9 g.) was added to a suspension of 7-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (1.54 g.) in dry ethyl acetate (30 ml.), and the mixture was stirred for 1 hour at 40° C. to give a clear solution. To this solution was added dropwise at -20° C. the above-obtained ethyl acetate solution, and the mixture was stirred for 1 hour at the same temperature. The reaction mixture was post-treated according to a similar manner to that of Example 12 to give pale yellow powder of 7-[2-methoxyimino-2-(1,2,3-thiadiazol-4-yl)acetamido]-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (0.9 g.).

1. customunder 10° C
2. stirringafter which the resulting mixture was stirred for 30 minutes at the same temperature
3. stirringthe mixture was stirred for 1 hour at 40° C.
4. customto give a clear solution
5. stirringthe mixture was stirred for 1 hour at the same temperature
6. additionThe reaction mixture was post-treated