2-Benzodioxinylaminoethanols: a new class of beta-adrenergic blocking and antihypertensive agents

Various 2-benzodioxinylaminoethanol derivatives were synthetized and investigated for beta-adrenergic blocking activity. Most compounds demonstrated a beta-blocking activity of a competitive type when evaluated in guinea pig atrial and tracheal preparations. Three compounds were more potent than practolol and propranolol. All compounds demonstrated antihypertensive properties in spontaneously hypertensive rats. The most active compound was 1-(1,4-benzodioxin-2-yl)-2-[N4-(2-methoxyphenyl)piperazino]ethanol (11), which at 2.5 mg/kg iv lowered blood pressure by 41%.