反应详情

温度

5 °C

To a mixture of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-(1-propenyl)-3-cephem-4-carboxylic acid (190 mg, 0.45 mmole) and potassium carbonate (75 mg, 0.54 mmole) in DMF (5 ml) was added at 5° C. 1-bromoethyl acetate** (90 mg, 0.54 mmole). The mixture was stirred at 5° C. for 1.5 hours and diluted with ethyl acetate (20 ml). The dilute was washed successively with water and a saturated aqueous NaCl solution, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was dissolved in chloroform and chromatographed on a silica gel column (5 g) with 1% methanol in chloroform. The desired fractions were combined and concentrated. The residue was dissolved in dioxane and lyophilized to yield 103 mg (45%) of the title compound as its dioxane solvate. Mp. 105°-110° C. Estimated purity 85% (by HPLC).

1. additionwas added at 5° C
2. washThe dilute was washed successively with water
3. dry with materiala saturated aqueous NaCl solution, dried over anhydrous magnesium sulfate
4. concentrationconcentrated in vacuo
5. dissolutionThe residue was dissolved in chloroform
6. customchromatographed on a silica gel column (5 g) with 1% methanol in chloroform
7. concentrationconcentrated
8. dissolutionThe residue was dissolved in dioxane