Novel hypoglycemic dihydropyridones serendipitously discovered from O- versus C-alkylation in the synthesis of VMAT2 antagonists.

Vesicular monoamine transporter type 2 (VMAT2) is a newly emerging target for both diagnostic and therapeutic applications in diabetes mellitus. In pursuit of novel VMAT2 antagonists, we identified a potent hypoglycemic agent with a novel dihydropyridone scaffold. Several analogs were designed and synthesized. A preliminary structure activity relationship (SAR) showed that the dihydropyridone scaffold is required for the activity.