N,N-Diisopropyl-3-(2-acyloxy-5-hydroxymethyl)-3-phenylpropylammonium salts (I) are new. Diphenylpropylamine derivative salts of formula (I) are new. [Image] R : 1-6C alkyl, 3-10C cycloalkyl or optionally substituted phenyl; X ->; : residue of an organic or inorganic acid. Independent claims are included for new diphenylpropylamine derivatives of formulae (II). [Image] Q 1 : COOMe; and Q 2 : H or benzyl; or Q 1 : CH 2OH; and Q 2 : H. ACTIVITY : Uropathic; spasmolytic. MECHANISM OF ACTION : None given.