BENZPYRINIUM BROMIDE

Originator

Stigmonene,Warner Lambert,US,1949

Manufacturing Process

56 grams of dimethylcarbamyl chloride were gradually added over a period of 50 minutes to a solution of 45 grams of 3-pyridol in a mixture of 300 cc of benzene and 69 grams of triethylamine. The reaction mass was then agitated at 80°C for 3 hours and permitted to cool. The triethylamine hydrochloride was removed by filtration and solvents distilled from the filtrate under vacuum in a nitrogen atmosphere. The residual oil was then fractionated under vacuum whereby, after removal of unchanged dimethylcarbamyl chloride, a product distilling at 90°C at 0.3 mm was obtained; this product was the dimethylcarbamyl ester of 3-pyridol.
60 grams of the ester prepared as above described were dissolved in 225 cc of benzene and 92.5 grams of benzyl bromide were added thereto. The solution was stirred at room temperature for 24 hours and refluxed for 3 additional hours. At the end of this time the crude product which formed was separated, washed with benzene and dissolved in water. The aqueous solution was extracted with ether, filtered through charcoal and then evaporated to dryness in a nitrogen atmosphere; traces of water were removed by redissolving the oily residue in absolute alcohol, adding benzene and then evaporating the mixture to dryness under vacuum. The yellow oil thus obtained was then dissolved in a mixture of 300 cc of benzene and 55 cc of absolute alcohol under reflux, the solution cooled, and 340 cc of absolute ether added. The solution was then seeded and maintained at 5°C for two days. The crystalline product obtained was filtered and dried, a product melting between 115°C and 116°C being obtained. This product was the desired 1 benzyl-3-(dimethylcarbamyloxy)-pyridinium bromide.

Therapeutic Function

Cholinergic