New synthetic route to 2-pyridones and its application toward the synthesis of (±)-ipalbidine

摘要

Six-membered nitrogen heterocycles comprise the back- bone of many biologically and structurally interesting alkaloids. ~1,2 The 3-hydroxy-2(1H)-pyridone (4) ring sys- tem is a valuable building block in natural product synthesis, ~3 as it can act as a common intermediate for the preparation of a wide variety of piperidine, pyridine, quinolizidine, and indolizidine alkaloids.