A series of gamma-methyl- (5) and alpha-methyl(aryloxy)propanolamines (6) were synthesized and evaluated for beta-adrenergic blocking action. The binding constant (KD) was determined for compounds 5a-j on cultured C6-2B astrocytoma cells. Compounds 5a-j and 6a-e were evaluated for beta 1-antagonist action on guinea pig atria and beta 2-antagonist action on guinea pig tracheal strips. Several gamma-methyl(aryloxy)propanolamines showed affinity for beta receptors and a possible preference for beta 2 receptors.