A series of prolyl-fluoropyrrolidine derivatives were designed, synthesized and screened for in vitro inhibition of dipeptidyl peptidase IV. The SAR study revealed the influence of substituted chemical modifications on dipeptidyl peptidase IV inhibitory activity. Among all the compounds screened, compound 9 (IC50= 0.83 lM) and 10 (IC50= 0.43 lM) possessing aryl substituted piperazine with acetamide linker resulted as most potent dipeptidyl ...