Abstract
To develop the first radiotracer targeting GPR91, a cell membrane-bound receptor that modulates the cellular response to hyperglycemia and hypoxia, we designed and prepared a small series of compounds based on a published series of 1,8-naphthyridines with high affinity to GPR91. Our approach provides a mechanism to incorporate radioactive atoms ((99m)Tc and (18)F) into the GPR91 pharmacophore as the final synthetic step. Pharmacological assays confirmed lead compounds for (99m)Tc and (18)F GPR91 radiotracers within the series.