Abstract: Novel alkanolamine derivatives of the formula: ##STR1## wherein Ar is phenyl or naphthyl which is unsubstituted or which bears one or two substituents selected from halogen, trifluoromethyl, hydroxy, amino, nitro, carbamoyl, carbamoylmethyl and cyano, and alkyl, alkenyl, alkoxy, alkenyloxy, alkylthio, alkanoyl and alkanoylamino each of up to 6 carbon atoms, or Ar is 4-indolyl, 4-benzo[b]thienyl, 5-benzo[1,4]dioxanyl, 4- or 5-indanyl, 5- or 6- 1,2,3,4-tetrahydronaphthyl), 2,3-dihydroxy-1,2,3,4-tetrahydronaphth-5-yl or 4- morpholino-1,2,5-thiadiazol-3-yl;wherein R is halogen;wherein A.sup.1 is alkylene of 2 to 6 carbon atoms; andwherein A.sup.2 is alkylene of 1 to 7 carbon atoms which in unsubstituted or bears a phenyl, hydroxy or carbamoyl substituent, or A.sup.2 is cycloalkylene of 3 to 6 carbon atoms;or acid-addition salts thereof.The compounds possess either .beta.-adrenergic blocking activity or diuretic activity or both such activities and may be used in the treatment of heart disease or hypertension.