Novel fluorine-containing 1,4-disubstituted piperidine derivatives, represented by general formula �I! ##STR1## such as, for example, (2R)-N-�1-(6-aminopyridin-2-ylmethyl)piperidin-4-yl!-2-�(1R)-3,3-difluorocyclopentyl!-2-hydroxy-2-phenylacetamide or pharmaceutically acceptable salt thereof, are potent and selective antagonists for muscarinic M.sub.3 receptors with little side effects. The compounds of formula �I! exhibit excellent oral activity, duration of activity and pharmacolkinetics. They are useful for treatment and prophylaxis of respiratory diseases, such as chronic obstructive pulmonary diseases; urinary diseases, such as urinary incontinence; and digestive diseases, such as irritable bowel syndrome, and motion sickness.