Phosphorus oxychloride → HCID 131712585, compound

Participants

Reaction Steps

The Vilsmeier reagent was prepared from dry dimethylformamide (0.44 g), phosphorus oxychloride (0.9 g) and dry ethyl acetate (1.0 ml) by the conventional method. Dry ethyl acetate (20 ml) was added thereto and then 2-methoxyimino-2-(2-formamidothiazol-4-yl)acetic acid (syn isomer)(1.1 g) was added thereto at -5° to -10° C. The mixture was stirred for 10 minutes at the same temperature. The resulting mixture was dropwise added at 0° to 5° C. and pH 6.5 to 7.5 with stirring to a solution of 7-amino-3-(4-allyl-4H-1,2,4-triazol-3-yl)thiomethyl-3-cephem-4-carboxylic acid (2.12 g) and sodium bicarbonate (2 g) in a mixture of water (20 ml) and acetone (20 ml), and the mixture was stirred for 20 minutes at the same temperature. The aqueous layer was separated and acetone was evaporated. The aqueous layer was adjusted under ice-cooling and stirring to pH 3.0 with 10% hydrochloric acid. Precipitates were collected by filtration, washed with water and dried to give 7-[2-methoxyimino-2-(2-formamidothiazol-4-yl)acetamido]-3-(4-allyl-4H-1,2,4-triazol-3-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer)(0.94 g).

Provenance & Evidence