摘要：N-Alkylephedrines were synthesized by heating a mixture of ephedrine and alkyl bromide under pressure. The alkylation proceeded with decreasing yield of the desired substance as the number of carbons of alkyl bromide increased, and there was, in the end, no yield at C5, viz., amyl bromide. With alkyl bromides of higher moleculer weight than amyl, the alkylation was successfully carried out by the addition of equimolar amount of pulverized KOH. The N-alkylephedrines thus obtained were converted to the ammonium salts with methyl or ethyl iodide. The pharmacological effects of the compounds synthesized were examined by the Magnus method and these effects were compared with that of l-ephedrine. Among these compounds, N-butyl-, N-hexyl-, N-heptylephedrines, and dimethylbutyl-(β-phenyl-β-hydroxyisopropyl) ammonium iodide were found to have pharmacological effects almost equal to that of l-ephedrine, in the balance of inhibitory effect on tonic contractions by acetylcholine, histamine, and barium chloride.
