Imidazopiperidine amides as dipeptidyl peptidase IV inhibitors for the treatment of diabetes

A series of substituted imidazopiperidine amides has been prepared and evaluated for inhibition of dipeptidyl peptidase IV (PP-4). Substitution at the 1- and 3-positions produced increased selectivity for DPP-4 relative to DPP-8 and DPP-9. Compounds in this series had IC50 values as low as 5.8 nM for inhibition of DPP-4. Published by Elsevier Ltd.