Synthesis and Structure-Activity Relationship Studies of Urea-Containing Pyrazoles as Dual Inhibitors of Cyclooxygenase-2 and Soluble Epoxide Hydrolase

A series of dual inhibitors containing a 1,5-diarylpyrazole and a urea were designed, synthesized, and evaluated as novel COX-2/sEH dual:inhibitors in vitro using recombinant enzyme assays and in vivo using a lipopolysaccharide (LPS) induced model of pain in rats. The best inhibition potencies and selectivity for sEH and COX-2 over COX-1 were obtained with compounds (21b, 211, and 21j) in which both the 1,5-diaryl-pyrazole group aid the urea group are linked with a three-methylene group. Compound 21i showed the best pharmacokinetic profiles in both mice and rats (higher AUC and longer half life). Following subcutaneous administration at 10 mg/kg, compound 21i exhibited antiallodynic activity that is more effective than the same dose of either a COX-2 inhibitor (celecoxib) or a sEH inhibitor (t-AUCB) alone, as well as coadministration of:both inhibitors. Thus, these novel dual inhibitors exhibited enhanced in vivo antiallodynic activity in a nociceptive behavioral assay.