Quinuclidine derivatives and their use as muscarinic M3 receptor antagonists

摘要

Disclosed is a compound of formula I, in salt or zwitterionic form, wherein R1 and R2 are each substituted phenyl, unsubstituted phenyl, C3-8cycloalkyl, or, together with R3 and the carbon to which they are attached, form a three-ring fused system selected from the list given in the specification, R4 is C1-8alkyl substituted at one to three positions by -CO-N(R5) R6, R6 is substituted isoxazolyl, and wherein the rest of the substituents are as described in the specification. Also disclosed is a process for preparing the compound. Also disclosed is the use of the compound for treating conditions mediated by the muscarinic M3 receptor, for inflammatory or allergic conditions, or inflammatory or obstructive airway diseases.