反应详情

Phosphoryl chloride (13.2 g.) was added dropwise to a stirred solution of N,N-dimethylformamide (6.3 g.) and tetrahydrofuran (24.7 ml.) at -5° C., and stirred at the same temperature for 30 minutes. Tetrahydrofuran (120 ml.) and 2-(2-formamidothiazol-4-yl)-2-n-butoxyiminoacetic acid (syn isomer, 19.5 g.) were added to the solution at -5° C., and stirred at the same temperature for 30 minutes. The solution was added dropwise a stirred suspension of 4-nitrobenzyl 7-amino-3-cephem-4-carboxylate (24.7 g.), tetrahydrofuran (120 ml.), acetone (60 ml.) and water (60 ml.) at -5° to 5° C. over 15 minutes while adjusting to pH 7 to 7.5 with 20% aqueous solution of sodium carbonate, and then the solution was stirred for 30 minutes. The insoluble substance was filtered off, and a saturated aqueous solution of sodium chloride was added to the filtrate. The solution was extracted with tetrahydrofuran twice. The extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and concentrated in vacuo. The residue was triturated with diisopropyl ether to give 4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-n-butoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 34.6 g.).

1. stirringstirred at the same temperature for 30 minutes
2. additionThe solution was added dropwise
3. stirringthe solution was stirred for 30 minutes
4. filtrationThe insoluble substance was filtered off
5. additiona saturated aqueous solution of sodium chloride was added to the filtrate
6. extractionThe solution was extracted with tetrahydrofuran twice
7. washThe extract was washed with a saturated aqueous solution of sodium chloride
8. dry with materialdried over magnesium sulfate
9. concentrationconcentrated in vacuo
10. customThe residue was triturated with diisopropyl ether