Glycogen Phosphorylase (GP) is the regulatory enzyme that catalyses the first step in glycogen degradation and is a potential enzyme target for therapeutic intervention in the treatment of diabetes. The 16 amino acid C-terminal sequence of human Gl is the only known targeting subunit that binds to GPa. Blocking the interactions between Gl and GPa should reduce high blood glucose levels in a diabetic person. A segment of the 16 amino acid segment was chosen for a small molecule peptidomimetric approach, and de nova design from this segment identified the pyridone ring as apotential scaffold. This thesis reports the design and synthesis of 1.3-disubstituted pyridones as new class of GPa inhibitors.