Hydrochloric Acid → 7-[2-(2-Aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(4-methoxy-1-pyridiniomethyl)-3-cephem-4-carboxylate

Beteiligte Stoffe

Reaktionsschritte

A mixture of 7-[2-(2-aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-acetoxymethyl-3-cephem-4-carboxylic acid (syn isomer) (3.0 g), 4-methoxypyridine (4.0 g), sodium iodide (8.0 g), acetonitrile (4.0 ml) and water (1.0 ml) was heated for 2.0 hours at 65° to 68° C., and then water (100 ml) was added thereto. The mixture was adjusted to pH 3.0 with 1N-hydrogen chloride and the resultant precipitates were filtered off. The aqueous layer was subjected to column chromatography on macroporus nonionic adsorption resin "Diaion HP-20" and the elution was carried out with 30% aqueous methanol. The fractions containing the object compound were collected, concentrated in vacuo and lyophilized to give 7-[2-(2-aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(4-methoxy-1-pyridiniomethyl)-3-cephem-4-carboxylate (syn isomer) (0.43 g).

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