反应详情

温度

51 °C

To a suspension of 7-amino-3 (1H-1,2,3-triazol-4-yl)thiomethylceph-3-em-4-carboxylic acid (31.3 g., 0.1 moles) in a mixture of 1,2-dimethyoxyethane (250 ml.) and concentrated HCl (12 ml., 0.138 moles) in water (50 ml.) was added 2,2-diethoxyethylcyanamide (52.05 g., 0.3 moles). The mixture was stirred and heated at 51° C. for 4 hours and the resulting solution was evaporated under reduced pressure to remove the 1,2-dimethoxyethane. The residual oil was diluted with water (250 ml.), the pH of the resulting suspension was adjusted to 4.8 using sodium bicarbonate and then filtered. The filtrate was applied to a column of "Amberlite" XAD-2 (500 ml.) ("Amberlite" is a Trade Mark). The resin was first washed with water (2000 ml.) and then eluted with 40% v/v aqueous methanol. The required fractions were combined and evaporated to dryness to give 7-(imidazol-2-yl)amino-3-(1H-1,2,3-triazol-4-yl)thiomethylceph-3-em-4-carboxylic acid (3.79 g., 10%) having an n.m.r. spectrum identical to the product of Example 5.

1. customthe resulting solution was evaporated under reduced pressure
2. customto remove the 1,2-dimethoxyethane
3. additionThe residual oil was diluted with water (250 ml.)
4. filtrationfiltered
5. washThe resin was first washed with water (2000 ml.)
6. washeluted with 40% v/v aqueous methanol
7. customevaporated to dryness