Abstract: The present invention relates to compounds of formula: ##STR1## in which: R.sub.3 is hydrogen, 2-tetrahydropyranyl or benzyl;R.sub.1 and R.sub.2 are such that:either R.sub.1 represents a methoxy group in which case R.sub.2 is a group chosen from the following: hydroxyl; C.sub.1 -C.sub.4 alkyl; C.sub.2 -C.sub.8 alkyloxy; C.sub.5 -C.sub.7 cycloalkloxy; benzyloxy;or R.sub.2 represents a methoxy group in which case R.sub.1 is a group chosen from the following: hydroxyl; C.sub.2 -C.sub.8 alkyloxy; C.sub.2 -C.sub.8 alkyloxy substituted by a methoxy group; C.sub.1 -C.sub.4 trifluoroalkyloxy; C.sub.3 -C.sub.4 alkenyloxy; C.sub.5 -C.sub.7 cycloalkyloxy; benzyloxy; C.sub.1 -C.sub.4 alkylthio;n=2 or 3; andp=4, 5 or 6,as well as their addition salts with mineral or organic acids, said compounds and salts being useful as drugs.

Abstract: Compounds of the formula ##STR1## wherein R, Y and R.sup.1 are as defined in the specification. These compounds are muscarinic receptor antagonists which are selective for smooth muscle muscarinic sites over cardiac muscarinic sites, and are useful in the treatment of diseases associated with altered motility on tone of smooth muscle, including irritable bowel syndrome, diverticular disease, urinary incontinence, oesophageal achalasia and chronic obstructive airways disease.