反应详情

in water (2 ml) containing sodium salt of 5-mercapto-1H-1,2,3-triazole (120 mg) and sodium hydroxide (40 mg) is dissolved under ice cooling 7β-amino-3-[2-(N-carboethoxycarbamoyl)benzoyloxy]methyl-3-cephem-4-carboxylic acid (450 mg) and to the mixture is added diluted hydrochloric acid to adjust its pH to 5.5 under stirring, followed by further stirring for one hour at 60° C. To the solution, is added methanol (5 ml) and the mixture is allowed to cool to the room temperature. The cooled mixture is adjusted its pH to 3.9 by adding diluted hydrochloric acid under stirring and the resultant mixture is further stirred for one hour under ice-cooling. The precipitate is collected by filtration and washed with water and methanol in this order and then dried over phosphorus pentoxide. The procedure provides 7β-amino-3-(1H-1,2,3-triazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (193 mg).

1. dissolutionis dissolved under ice
2. stirringby further stirring for one hour at 60° C
3. stirringunder stirring
4. temperaturecooling
5. filtrationThe precipitate is collected by filtration
6. washwashed with water and methanol in this order
7. dry with materialdried over phosphorus pentoxide