Pharmacologically active R(-) 3-quinuclidinol derivatives are described which are muscarinic receptor blocking agents useful for the treatment of gastrointestinal and respiratory tract disorders of the following formula (I)

wherein
R represents a linear or branched lower alkyl group, a cycloalkyl-C₁₋₂alkyl or an aralkyl group, or it is absent;
X represents the anion of an organic or inorganic acid, or it is absent, when R is absent;
R₁ represents H, a linear or branched lower alkyl group or an acyl group of the type R₂-CO, in which R₂ is H or a linear or branched lower alkyl group;
A represents a cycloalkyl, an aromatic ring or a 5- or 6-membered heterocyclic ring;
Y and Z may be simultaneously or alternatively present or absent; when they are simultaneously present, they represent oxygen; when only one of them is present, it is oxygen or sulphur;
n is 1, 2 or 3;
A and the 3-quinuclidinyl ester groups are inserted simultaneously on the same carbon atom of the ring to give rise to a geminal substitution.
The process of the preparation of the compounds of formula (I) as well as pharmaceutical compositions containing them are also described.