The compounds 2-Aryl-3-amino-1-butanol derivatives of the formula ##STR1## wherein R represents hydrogen or acyl; R.sup.1 and R.sup.2 each independently represents hydrogen, phenyl lower alkyl, or lower alkoxy substituted phenyl lower alkyl, or both R.sup.1 and R.sup.2 are lower alkyl; and their pharmaceutically acceptable acid salts. The compounds are crystalline solids or liquids which, having two asymmetry centers, can be obtained in their stereoisomeric forms as racemic mixtures or in their optically active forms. The compounds have cardiovascular activity as coronary dilators. The compounds can be prepared by reacting an .alpha.-arylcrotonate with ammonia or with an amine followed by hydrogenation of the carbalkoxy group to give the corresponding butanol. The butanols are acylated in usual ways to give the compounds of formula (I) wherein R represents an acyl group.