THE SYNTHESIS OF A NEW ADRENERGIC BETA-RECEPTORBLOCKING AGENT 6-(2-ISOPROPYLAMINO-1-HYDROXYETHYL)-1,4-BENZODIOXANE

Bromination of 6-acetyl-1,4-benzodioxane gave 6-(α-bromoacetyl)-1,4-benzodioxane (IVb), which was condensed with isopropylamine, forming 6-(α-isopropylaminoacetyl)- 1,4-benzodioxane (IVc). The latter compound afforded the desired aminoethanol (III) upon reduction with potassium borohydride.Pharmacological examinations revealed that III was more potent in adrenergic beta-blocking effect, but was less toxic in comparison with pronethalol.