Etifelmine (INN; also known as gilutensin) is a stimulant drug. It was used for the treatment of hypotension (low blood pressure).
The base-catalyzed reaction between benzophenone (1) and butyronitrile (2) gives 2-[hydroxy(diphenyl)methyl]butanenitrile (3). Catalytic hydrogenation reduces the nitrile group to a primary amine giving 1,1-diphenyl-2-ethyl-3-aminopropanol (4). The tertiary hydroxyl group is dehydrated by treatment with anhydrous hydrogen chloride gas, completing the synthesis of etifelmine (5).