This invention relates to compounds which exhibit selective muscarinic M.sub.3 receptor antagonism, have little side effects, are suitable for inhalation therapy and are useful as treating agents of respiratory system diseases, of the general formula (I); [in which A signifies a group expressed by a formula (a.sub.0) or (b.sub.0); Ar signifies optionally substituted aryl or heteroaryl; B.sup.1 and B.sup.2 signify aliphatic hydrocarbon; R.sup.1 signifies fluorine-substituted cycloalkyl; R.sup.2, R.sup.3 and R.sup.4 signify lower alkyl, single bond or alkylene bonded to B.sup.1, or R.sup.2 and R.sup.3 are united to signify alkylene; R.sup.5 and R.sup.7 signify hydrogen, lower alkyl, or a single bond or alkylene bonded to B.sup.2; R.sup.6 signifies hydrogen, lower alkyl or a group expressed as --N(R.sup.8)R.sup.9; and X.sup.-signifies an anion].