Sodium Carbonate → 4-Nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-n-butoxyiminoacetamido]3-cephem-4-carboxylate

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Reaction Steps

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.).

Provenance & Evidence