Design, Synthesis, and Biological Evaluation of Novel Quinazoline Clubbed Thiazoline Derivatives.

A novel series of quinazoline clubbed thiazoline derivatives was rationally designed and synthesized. The newly synthesized compounds were evaluated for in vitro dipeptidyl peptidase IV (DPP-4) inhibitory activity. Compounds that showed good to moderate activity were compared using linagliptin as standard. Compound 4x (IC50  = 1.12 nM) exhibited the most promising results. The special chemical feature of compound 4x also imparts good inhibition selectivity for DPP-4 over DPP-8/9. Moreover, docking of compound 4x into the active site of DPP-4 illustrates its possible binding interactions.