Synthesis and evaluation of novel 2-pyridone derivatives as inhibitors of phosphodiesterase3 (PDE3): a target for heart failure and platelet aggregation.

Twenty-six 2-pyridone derivatives (8a-8z), which are structurally analogous to amrinone and milrinone two important cardiotonic drugs, are synthesized and characterized. The synthesis of 2-pyridone derivatives involves addition, followed by cyclization between Baylis-Hillman acetates (7a-7k) and enamino esters or nitriles (3a-3e). Thus synthesized pyridones were subjected to PDE3 inhibitory activity, 14 pyridones were found to be hits out of 26 pyridones synthesized and out of 14 hits, there are 5 pyridones found to be lead compounds having excellent PDE3 inhibitory activity. Further we have carried out computational analysis to understand protein/enzyme and 2-pyridone derivative interactions to identify amino acid residues involved in the vicinity of binding and compared with milrinone drug.

Synthesis and biological evaluation of new epalrestat analogues as aldose reductase inhibitors (ARIs).

Baylis-Hillman chemistry derived four series of new epalrestat analogues were synthesized. Three structural changes are introduced in these 39 new epalrestat analogues synthesized. All compounds were evaluated for their in vitro aldose reductase inhibitory (ALR) activity. Biological activity data indicates that compounds 6, 16, 19, 28 and 29 are potent and the activity is in the range of reference drug, epalrestat. Molecular modelling studies were performed to understand the binding interactions of these active molecules with the ALR protein. Molecular docking data indicates the key interactions of epalrestat were retained in some of the active compounds whereas some new interactions were noticed for other molecules. The modifications introduced on epalrestat have impact for developing a new-type of ALR inhibitor.