Pharmaceutical compositions containing as an active ingredient a racemic or optically active compound of the formula ##STR1## wherein R.sub.1 is hydrogen, halogen, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms, and R.sub.2 is straight or branched hydroxyalkyl of 3 to 6 carbon atoms, Or a non-toxic, pharmacologically acceptable acid addition salt thereof; and a method of using the same as .beta.-adrenergic receptor blocking agents and hypotensives.
                            含有以下公式中的外消旋或旋光性化合物作为活性成分的制药组合物:##STR1## 其中R.sub.1是氢、卤素、1至4个碳原子的烷基或1至4个碳原子的烷氧基,而R.sub.2是3至6个碳原子的直链或支链羟基烷基,或其无毒、药理学上可接受的酸加成盐;以及将其用作β-
肾上腺素能受体阻滞剂和降压剂的方法。