| abstract |
<IMAGE> (I) 3-Quinuclidinyl butanoate and propanoate antimuscarinic bronchodilators, particularly useful in the treatment of chronic obstructive airways disease and asthma, of formula (1), and their pharmaceutically acceptable salts, wherein X is either (a) a phenyl group optionally substituted by one or two substituents each independently selected from halo. CF3, C1-C4 alkyl, C1-C4 alkoxy and hydroxy or (b) a thienyl group; and "Het" is either (a) a 5-membered nitrogen-containing heterocyclic group attached to the adjacent carbon atom either by a carbon or a ring nitrogen atom and which is selected from imidazolyl, pyrazolyl, triazolyl and tetrazolyl. (b) an oxadiazolyl or thiadiazolyl group attached to the adjacent carbon atom by a carbon atoms, or (c) a 6-membered nitrogen-containing heterocyclic group attached to the adjacent carbon atom by a carbon atom and selected from pyridinyl, pyrazinyl, pyrimidinyl and pyridazinyl, "Het" being optionally substituted by up to two substituents each independently selected from halo, CF3, C1-C4 alkyl, C1-C4 alkoxy, hydroxy, amino and azido; and m is 1 or 2. |