Design, synthesis and in vitro activity of glycinamide-bearing compounds as DPP-IV inhibitors

To research the structure-activity relationship (SAR) of glycinamide-bearing compounds that  used as inhibitors of dipeptidyl peptidase IV (DPP-IV), P32/98 and compound A were chosen as the leading compounds, heterocycles containing nitrogen atom were introduced to form amide, and different residues on α-position of carbonyl were designed.  The nineteen designed compounds were synthesized by a simple route and were evaluated as inhibitors of DPP-IV.  All of the structures were characterized by ¹H NMR and HRMS.  The preliminary SAR result was obtained.