Design, Synthesis and Biological Evaluation of New 1,3-diphenyl-3- (phenylamino)propan-1-ones as Selective Cyclooxygenase (COX-2) Inhibitors.

Abstract

Prostaglandins are a family of eicosanoids biosynthesized from arachidonic acid through cyclooxygenase (COX) pathway. Two isoforms of COX are well established: COX-1, COX-2. Evidence supports the notion that cyclooxygenase-2, plays a crucial role in some pathological conditions such as inflammation and cancer. A new group of 1,3-diphenyl-3-(phenylamino)propan-1-ones was designed and synthesized to investigate for their COX-2 inhibitory activity and inhibition of platelet aggregation. Docking study was performed using AutoDock vina software. In vitro COX-1 and COX- 2 isozyme inhibition studies were accomplished to obtain structure activity relationship data. The in vitro antiplatelet aggregation activity was determined by turbidimetric procedure. In vitro COX inhibition assay showed that except compound 8c, all derivatives were selective COX-2 inhibitors with IC50 values in the potent 0.20-0.35 µM range with high COX-2 selectivity indexes (SI). Molecular modeling and docking studies indicated that synthesized compounds had a binding similar to that of the known inhibitor SC-558 and the SO2Me group was inserted into the COX-2 secondary pocket (Val523, Phe518, Ile517, Arg513 and His90) and C=O of the central α, β-unsaturated-carbonyl moiety was oriented toward the entrance to the COX-2 binding site (Tyr355 and Arg120). The 1,3-diphenyl-3-(phenylamino)propan-1-ones are novel COX-2 inhibitors with good COX-2 inhibitory and low affinity for COX-1 isoenzyme. Also our results demonstrated that majority of these compounds inhibited AA-induced platelet aggregation.