Discovery of novel urea-diarylpyrazole hybrids as dual COX-2/sEH inhibitors with improved anti-inflammatory activity and highly reduced cardiovascular risks

Herein we describe our efforts to develop novel anti-inflammatory/analgesic agents devoid of known cardiovascular drawbacks. In doing so, two 1,5-diarylpyrazole series of urea linked (9a-f) and amide linked (11a-f) compounds were synthesized and evaluated in vitro as dual COX-2/sEH inhibitors using recombinant enzyme assays. The in vivo anti-inflammatory and analgesic activities were then examined using reported animal models. Compounds 9b and 9c showed the highest inhibitory activities against both COX-2 and sEH (IC₅₀ of COX-2 = 1.85 and 1.24 μM; sEH = 0.55 and 0.40 nM, respectively), besides showing the best activity as anti-inflammatory agents. Interestingly, the cardiovascular profile of the two compounds 9b and 9c was evaluated through measuring some biochemical parameters such as prostacyclin (PGI₂), lactate dehydrogenase (LDH), troponin-1 (Tn-1), tumor necrosis factor- α (TNF-α), creatine kinase-M (CK-M) and reduced glutathione (GSH) in addition to a histo-pathological study to investigate the changes in the heart muscle. The results confirmed that compounds 9b and 9c have a more favorable cardio-profile than celecoxib with much less cardiovascular risks associated with the common selective COX-2 inhibitors. Finally, the current work provided a promising approach that can be optimized to serve as a lead project to overcome the cardiovascular toxicity related to the traditional selective COX-2 inhibitors.

Keywords: 1,5-Diarylpyrazole; Anti-inflammatory; Cardiotoxicity; Dual COX-2/sEH; sEH inhibitor.