BENZPHETAMINE HCL

Originator

Didrex,Upjohn,US,1960

Manufacturing Process

Fifty grams of d-desoxyephedrine hydrochloride was dissolved in a small amount of water and a molar excess of sodium hydroxide was .added thereto. The resulting forty grams of precipitated oily d-desoxyephedrine was collected in ether and the whole was thereafter dried with anhydrous potassium carbonate. The ether was then removed, the resulting oily residue having an nD22 of 1.5045 was stirred in a flask with 40 grams of anhydrous sodium carbonate at 120°C, and 34.6 grams of benzyl chloride was added dropwise thereto over a period of thirty minutes. Stirring was continued for 2 hours, whereafter the reaction mixture was extracted with benzene.
The benzene was distilled from the extract and the residue of d-N-methyl-Nbenzyl-β-phenylisopropylamine was distilled at reduced pressure. The thus obtained free base, distilling at 127°C at a pressure of 0.2 mm of mercury and having an nD19 of 1.5515, was dissolved in ethyl acetate and a molar equivalent of ethanolic hydrogen chloride was added thereto. Anhydrous ether was added to the mixture and d-N-methyl-N-benzyl-β-phenylisopropylamine hydrochloride precipitated from the reaction mixture as an oil which was crystallized from ethyl acetate to give crystals melting at 129° to 130°C.

brand name

Didrex (Pharmacia & Upjohn).

Therapeutic Function

Antiobesity

General Description

Benzphetamine hydrochloride, (+)-N-benzyl-N, -dimethylphenethylaminehydrochloride, (+)-1-phenyl-2-(Nmethyl-N-benzylamine)propane hydrochloride (Didrex), isN-benzyl–substituted methamphetamine. The large (benzyl)N-substituent decreases excitatory properties, in keepingwith the general structure–activity relationship (SAR) forthe group. Anorexiant properties are retained. Classically,amphetamine-like drugs with larger than N-methyl substituentsare cited as anorexiant through central β-agonism.No claims for selectivity among β-receptor subtypes havebeen made in such citations. The compound shares mechanism-of-action characteristics with methylphenidate.Overall, it is said to reduce appetite with fewer CNS excitatoryeffects than dextroamphetamine.

Raw materials

Preparation Products