The invention is concerned with novel imidazopyridine derivatives of formula (I)wherein R1, R2, R3, R4, R5and 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 as medicaments.本發明係關於式(I)之新穎咪唑并吡啶衍生物其中R1、R2、R3、R4、R5及A係如本說明書及申請專利範圍中所定義,以及其生理學上可接受之鹽及酯。該等化合物抑制PDE10A且可用作藥劑。