反应详情

To a mixture of 7-amino-3-[3-(4-carbamoylpyridinio)-1-(E)-propenyl]-3-cephem-4-carboxylic acid hydrochloride (XXII-H, 397 mg, 1 mmole) and NaHCO3 (168 mg, 2 mmoles) in aqueous DMF (water, 3.5 ml and DMF, 7.5 ml) was added benzotriazol-1-yl-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-methoxyiminoacetate (479 mg, 1.5 mmoles) (from Preparation No. 28). The mixture was stirred at room temperature for 3.5 hours. The reaction mixture was adjusted to pH 3-4 with 3N HCl and diluted with 200 ml of acetone to give a precipitate, which was collected by filtration. The crude product was dissolved in a small volume of aqueous THF and the solution was adjusted to pH 6.8 with NaHCO3, treated with decolorizing carbon, concentrated to ca. 1 ml and seeded with a few pieces of crystalline I-1H. After stirring overnight, the crystalline precipitate was collected by filtration to afford the title compound I-1H (zwitterion form). Yield 83 mg (16%). Mp. >185° C. (dec.). Physico-chemical data of this product were identical to those of the compound in Example 10.

1. customto give a precipitate, which
2. filtrationwas collected by filtration
3. dissolutionThe crude product was dissolved in a small volume of aqueous THF
4. additiontreated with decolorizing carbon
5. concentrationconcentrated to ca. 1 ml
6. stirringAfter stirring overnight
7. filtrationthe crystalline precipitate was collected by filtration