Ammonia → HCID 131712336, compound

Participants

Reaction Steps

Tetrahydrofuran (24 ml.) and 4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-carboxymethoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 3.07 g.) were added to Vilsmeier reagent prepared from N,N-dimethylformamide (0.756 g.) and phosphoryl chloride (1.59 g.) in tetrahydrofuran (6 ml.) at -10° to -5° C. and then stirred at the same temperature for 30 minutes. The solution was added dropwise to a mixture of tetrahydrofuran (50 ml.) and water (25 ml.) at -5° to 0° C. while keeping at pH 9 to 9.5 with aqueous ammonia, and stirred for 20 minutes at pH 7.5. After adjusting the resultant solution to pH 2.0 with 10% hydrochloric acid, tetrahydrofuran was removed in vacuo. Water was added to the residue and extracted with ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride twice, an aqueous solution of sodium bicarbonate five times and a saturated aqueous solution of sodium chloride twice in turn, dried over magnesium sulfate and then concentrated in vacuo. The residue was pulverized with diethyl ether, collected by filtration and dried to give 4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-carbamoylmethoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 1.8 g.).

Provenance & Evidence