反应详情

温度

0 °C

A 3.5 ml portion of acetonitrile was added to 0.946 g of 7-amino-3-(2-carboxybenzoyloxy)methyl-3-cephem-4-carboxylic acid and 0.32 g of 5-mercapto-1-methyl-1H-tetrazole, and the mixture was cooled over a dry-ice/ethanol bath, followed by adding through a dropping funnel 3.71 g of DCPA to it with stirring and rinsing the funnel with 1.0 ml of acetonitrile. The external bath was removed, and the reaction mixture was warmed to 0° C., whereby the starting materials dissolved. The solution was stirred at 14° to 16° C. for 40 minutes to allow the reaction to proceed, and the reaction solution was cooled with ice, and poured into ice-water, which was placed in a refrigerator overnight. The precipitate was filtered out and washed with 10 ml of water, and the filtrate and washing were combined and adjusted to pH 4.0 with 25% aqueous ammonia under ice cooling. The precipitated powder was recovered by filtration, washed with water and acetone successively, and dried, thereby affording 0.710 g (86.5% of yield) of 7-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid. The IR and NMR values of the product were in accordance with those of the authentic sample.

1. temperaturethe mixture was cooled over a dry-ice/ethanol bath
2. washrinsing the funnel with 1.0 ml of acetonitrile
3. customThe external bath was removed
4. dissolutionwhereby the starting materials dissolved
5. stirringThe solution was stirred at 14° to 16° C. for 40 minutes
6. customthe reaction
7. temperaturethe reaction solution was cooled with ice
8. customwas placed in a refrigerator overnight
9. filtrationThe precipitate was filtered out
10. washwashed with 10 ml of water
11. washthe filtrate and washing
12. filtrationThe precipitated powder was recovered by filtration
13. washwashed with water and acetone successively
14. customdried