The present invention relates to highly pure, crystalline, stable compounds of novel derivatives of 3,3-diphenylpropylamines in the form of their salts of the general formula I, and to a process for their preparation by making use of highly pure, stable intermediate products of the general formula 1. The invention also relates to a process for preparing the above-described derivatives wherein the preparation process thereof is characterized in that a compound of the general formula III is split with a hydrogenation agent to form a compound of the general formula V whereupon the compound of the general formula V so obtained is converted with a reducing agent, in order to give a compound of the general formula VI, which is converted with an acylation agent, in order to obtain a compound of the general formula A, which is converted with a physiologically compatible inorganic or organic acid to form a compound of the general formula I wherein the preparation process is particular further characterized by regio- and chemoselectivity and high yield.Anvendelse av R-(+)-2-(3 -diisopropylamino-l-fenylpropyl)-4-hydroksymetyl-fenylisosmørsyre- hydrogenfimiarat eller den krystallinske form av R-(+)-2-(3-diisopropylamino-l-fenylpropyl)-4- hydroksymetyl-fenylisosmørsyrehydrogenfimiaratfor fremstilling av et medikament for behandling av urininkontinens og andre spasmogeniske sykdommer.
