Substituted phenylpiperazinyl-propanols, a process for their preparation and their use, and formulations containing these compounds

Substituted phenylpiperazinyl-propanols of the formula I (I) in which R1 denotes hydrogen or an alkyl group with 1 to 4 carbon atoms and R2 and R3, which can be identical or different, each denote hydrogen, halogen, cyano, a trifluoromethyl group, a nitro group, a hydroxyl group, an alkoxy group or an alkyl group with in each case 1 to 4 carbon atoms, it being possible for the alkyl parts in each case to be straight-chain or branched, and their tautomeric forms and their salts as well as acid addition salts and N-oxides, have useful pharmacological properties, in particular a positively inotropic, vasodilating, broncholytic and platelet aggregation-inhibiting action and are therefore suitable for the treatment of cardiac insufficiency, hypertension, asthma and thrombosis.