The invention is concerned with novel imidazopyridine derivatives of formula (I) wherein R1, R2, R3, R4, R5 and A are as defined in the description and in the claims, as well as physiologically acceptable salts and esters thereof. These compounds inhibit PDE10A and can be used for the treatment of various diseases, including central nervous system disorders such as Alzheimer's disease, Parkinson's disease, and schizophrenia.
