Total synthesis of lodopyridone

A convergent total synthesis of the structurally unprecedented alkaloid lodopyridone was achieved using a cross-coupling of an iodopyridone fragment with a quinolinethiazolylstannane. Key features of the syntheses of the pentasubstituted 4-pyridone were a regioselective bromination of a 4-pyridone derived from kojic acid, a subsequent Cu-mediated introduction of the thioether, and a directed lithiation/iodination step. A chemoselective Negishi cross-coupling of a dibromothiazole and a quinolinylzinc reagent was used to assemble the chloroquinolinethiazol moiety.