The synthesis of a series of (3-hydroxyprop-1-enyl)-substituted 1-(aryloxy)-3-(alkylamino)propan-2-ols is described. These compounds were investigated for their beta-adrenoreceptor blocking properties and their selective of action. Among the o-(hydroxypropenyl)-substituted derivatives we have found some potent noncardioselective beta-adrenoreceptor blocking agents which have a greater blocking action