| abstract |
This invention provides compounds of formula I: n n n n n n n n n n wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , Ar 1 , Ar 2 , E, a, b, c and z are as defined in the specification, or a pharmaceutically acceptable salt or solvate or stereoisomer thereof. The compounds of this invention possess both β 2 adrenergic receptor agonist and muscarinic receptor antagonist activity and therefore, such compounds are useful for treating pulmonary disorders, such as chronic obstructive pulmonary disease and asthma. |