A compound which is an ethanolamine derivative of formula (I), wherein R<1> is a pyridyl or NR<2>R<3> group, wherein R<2> is hydrogen or a C1-C4 alkyl or methanesulphonyl group and R<3> is a C2-C4 alkanoyl group, an unsubstituted phenyl group or a phenyl group substituted by a carbamoyl group; m is from 4 to 8; and n is 2 or 3; or a pharmacologically acceptable salt thereof, has agonist activity on the adrenergic beta -receptors of the bronchus.
