1218-35-5

Manufacturing Process

62 grams of para-tertiany-butyl-ortho,ortho'-dimethyl-phenyl-acetonitrile [obtainable, for example, by the method of Buu-Hoi and P. Cagniant, Bulletin de la Societe Chimique de France, volume 9, page 891 (1942)], 20.6 grams of ethylenediamine of 96% purity and 1.55 cc of carbon disulfide are heated together in a distillation flask with the exclusion of moisture for 48 hours on a boiling water bath. Ammonia is evolved. Upon cooling the reaction product solidifies and is then dissolved in benzene, the solution is filtered while hot with the addition of animal charcoal and petroleum ether is added. The mixture is filtered to remove the impurities that are first precipitated and by the further addition of petroleum ether 2-(para-tertiary-butyl-ortho,ortho'- dimethyl-phenyl-methyl)-imidazoline is caused to crystallize out.The product melts at 131° to 133°C after being recrystallized from a mixture of benzene and petroleum ether. It can be converted into its hydrochloride as follows:189 grams of 2-(para-tertiary-butyl-ortho,ortho'-dimethyl-phenyl-methyl)- imidazoline are dissolved in 400 cc of absolute ethanol, the solution is rendered acid by the addition of 104 cc of an ethanolic solution of hydrochloric acid of 30% strength, the mixture is filtered with the addition of animal charcoal, and dry ethyl acetate and absolute ether are added until crystallization sets in. After cooling the mixture, the salt is filtered off with suction and crystallized several times from absolute ethanol with the use of animal charcoal and the addition of dry mixture of ethyl acetate and ether. The hydrochloride so obtained melts at 327° to 329°C (with decomposition).

Biochem/physiol Actions

α-adrenoceptor agonist; imidazoline binding site ligand.

Safety Profile

Poison by ingestion, subcutaneous, intravenous, and intraperitoneal routes. When heated to decomposition it emits toxic fumes of NOx and HCl.

Brand name

Neo-Synephrine II (Sterling Winthrop); Otrivin Hydrochloride (Ciba-Geigy).

General Description

Xylometazoline hydrochloride is a derivative of imidazole, and a representative of the class of α1 agonists. It is commonly used in nasal decongestants, which works on the principle of constricting the blood vessels in the mucous membranes.