Phosphorus oxychloride → HCID 131712579, compound

Participants

Reaction Steps

The Vilsmeier reagent was prepared from dry dimethylformamide (0.526 g), phosphorus oxychloride (1.10 g) and dry ethyl acetate (1.5 ml) by the conventional method. Ethyl acetate (10 ml) was added thereto and then 2-methoxyimino-2-(2-formamidothiazol-4-yl)acetic acid (syn isomer) (1.50 g) was added thereto at 0° C. The mixture was stirred for 30 minutes at the same temperature. The resulting mixture was added under -10° C. to a stirred solution of 7-amino-3-(1-allyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (2.32 g) and trimethylsilylacetamide (6.18 g) in dry ethyl acetate (30 ml), and the mixture was stirred for 1 hour at the same temperature. The reaction mixture was extracted by adding ethyl acetate (20 ml) and water (30 ml). The ethyl acetate layer was separated and extracted with a saturated aqueous solution of sodium bicarbonate (20 ml). The aqueous layer was adjusted to pH 2.0 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-(1-allyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (2.60 g).

Provenance & Evidence