Synthesis of thio-heterocyclic analogues from Baylis-Hillman bromides as potent cyclooxygenase-2 inhibitors.

A series of thio-substituted pyrimidine, benzoxazole, benzothiazole and triazole analogues were synthesized from Baylis-Hillman bromides in a clean and efficient way. The synthesized twenty new compounds were subjected to in vitro COX-1 and COX-2 inhibitory activity. Majority of compounds found to be highly selective COX-2 inhibitor. Seven compounds (16e, 16f, 16k, 16l, 16m, 16r and 16s) displayed anti-inflammatory activity at micromolar concentrations with IC50 values for COX-2 inhibition ranging from 2.93 to 5.34 µM compared to reference drug whose IC50 is 2.66 µM. All these seven compounds had very little COX-1 inhibition property and thus are suitable candidates for anti-inflammatory drugs with less gastrointestinal side effect.

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.