Hydrochloric Acid → 2-Methyl-7-[2-hexyloxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid

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Reaction Conditions

Reaction Steps

A solution of 2-methyl-7-[2-hexyloxyimino-2-(2-formylaminothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid (syn isomer), which can be represented as 2-methyl-7-[2-hexyloxyimino-2-(2-formylimino-2,3-dihydrothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid (syn isomer), (5.3 g) and concentrated hydrochloric acid (4.2 g) in a mixture of methanol (53 ml) and tetrahydrofuran (40 ml) was stirred for 2 hours at 30° C., and then evaporated to dryness. The residue was dissolved in an aqueous solution of sodium bicarbonate (500 ml) and then filtered. The filtrate was adjusted to pH 3.5 with 10% hydrochloric acid with stirring under ice-cooling and further stirred for 30 minutes at the same temperature. The precipitates were collected by filtration, washed with water and then dried to give 2-methyl-7-[2-hexyloxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid (syn isomer), which can be represented as 2-methyl-7-[2-hexyloxyimino-2-(2-imino-2,3-dihydrothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid (syn isomer), (4.45 g).

Provenance & Evidence