Synthesis of New Naproxen Derivatives

Non-steroidal anti-inflammatory drugs (NSAIDs) are the competitive inhibitors of cyclooxygenase (COX), the enzyme which mediates the bioconversion of arachidonic acid to inflammatory prostaglandins. Their use is associated with the side effects such as gastrointestinal problems. The therapeutic anti-inflammatory action of NSAIDs is produced by the inhibition of COX-2, while the undesired side effects arise from inhibition of COX-1 activity. Thus, it was thought that selective COX-2 inhibitors would have reduced side effects.Therefore, pyrazoline ring derivatives as a pharmacophore were incorporated to the naproxen; to increase its size were synthesized and preliminarly evaluated as potential anti-inflammatory agents with expected selectivity toward COX-2 enzyme.Synthesis of the target compounds (Va-f) has been successfully achieved. Purity, characterization, and identification of the synthesized compounds were detected by determination of physical properties (melting points & Rf values), Fourier transform infrared spectroscopy (FT-IR) and 1H-Nuclear magnetic resonance (1H-NMR) spectroscopy.