Claisen reaction of 3,4-dimethoxyphenylacetonitrile with ethyl phenylacetate, the following stepwise hydrolysis and decarboxylation afforded the amide V 1-(3,4-dimethoxyphenyl)-3-phenylpropan-2-one (VI). Leuckart reaction resulted in the crude formamide derivative IIIb which was subjected to alkaline hydrolysis to the primary amine Ib on the one hand, and to reduction to the secondary amine IIb on the other. Demethylation with hydrobromic acid gave hydrobromides of 1-(3,4-dihydroxyphenyl)-3-phenyl-2-propylamine (title compound Ia) and its N-methyl derivative IIa. The alcohol VII, obtained by reduction of the ketone VI, was transformed by treatment with thionyl chloride to the chloro compound VIII which afforded by substitution reaction with 1-methylpiperazine the piperazine derivative IX. While the methoxylated amines Ib and IIb have mild stimulating and some antiarrhythmic effects, N-methyl-α-benzyldopamine (IIa) displayed a clear dopaminomimetic character.
3,4-二甲氧基苯乙腈与苯乙酸乙酯进行Claisen反应,随后逐步水解和脱羧得到酰胺V 1-(3,4-二甲氧基苯基)-3-苯基丙酮VI。Leuckart反应产生粗品酰胺衍生物IIIb,经碱性水解得到一方面的一级胺Ib,另一方面还还原成二级胺IIb。用氢溴酸去甲基化得到1-(3,4-二羟基苯基)-3-苯基-2-丙胺氢溴酸盐(标题化合物Ia)及其N-甲基衍生物IIa。通过还原酮VI得到醇VII,经硫酰氯处理转化为氯化合物VIII,再通过与1-甲基哌嗪的取代反应得到哌嗪衍生物IX。而甲氧基化胺Ib和IIb具有轻微的刺激作用和一些抗心律失常作用,N-甲基-α-苄基多巴胺IIa则表现出明显的多巴胺拟态特性。