反应详情

2,2,2-Trifluoroacetic anhydride (2.12 g) was dropwise added to a stirred solution of 2-n-octyloxy-1-n-octyloxymethylethyl 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate-1-oxide (syn isomer, 2.34 g) and sodium iodide (1.56 g) in dry acetone (40 ml) at 0° to 5° C. over 45 minutes, and stirred at 0° to 5° C. for 2 hours. The resultant mixture was poured into ice water (200 ml), and then extracted with ethyl acetate (110 ml). The extract was washed with an aqueous solution of sodium thiosulfate, an aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in turn, and then dried over anhydrous magnesium sulfate. After evaporating the solution in vacuo, the residue was subjected to column chromatography, on silica gel (100 g) with a mixture of chloroform and methanol (20:1). The eluate was evaporated in vacuo to give powder (1.57 g) of 2-n-octyloxy-1-n-octyloxymethylethyl 7-[2-(2-formamidothiazol-4 -yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 1.57 g).

1. extractionextracted with ethyl acetate (110 ml)
2. washThe extract was washed with an aqueous solution of sodium thiosulfate
3. dry with materialan aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in turn, and then dried over anhydrous magnesium sulfate
4. customAfter evaporating the solution in vacuo
5. additionthe residue was subjected to column chromatography, on silica gel (100 g) with a mixture of chloroform and methanol (20:1)
6. customThe eluate was evaporated in vacuo