[Correlations between chemical structure and cardiac effectivity of a group of beta-receptor blockaders]

13 compounds from the families of halogenated phenylethanolamines and phenoxypropanol-amines were tested for their antagonistic effect against an isoproterenol-induced increase in heart rate and lowering of blood pressure, and the AD50 values were determined. All the substances had beta-adrenolytical effects. 2.4-Difluoroisoproterenol and 1-(2.4-dichlorophenoxy)-3-t-butylaminopropanol-(2) showed a higher affinity to the beta1-receptors of the heart than to the beta2-receptors of the vessels. Correlations existing between chemical structure and action on the adrenergic beta-receptors are described.