Non-steroidal anti-inflammatory drugs (NSAIDs) contain free –COOH which thought to be responsible for the GI irritation associated with all traditional NSAIDs. The esterification of this group is one of an approach to ultimate aim for reduce the gastric irritation; so in this study we synthesized and preliminarily evaluated new ester compounds as new analogues with expected selectivity toward COX-2 enzyme. Synthetic procedures have been successfully developed for the generation of the target compounds (III a and b). The synthetic approach involved multi-steps procedures which include: Synthesis of 4-hydroxy benzene sulphonamide ( I b ), synthesis of Naproxen and Ibuprofen acyl chloride and then reacting them with 4-hydroxy benzene sulphonamide to form final compounds ( III a-b) .The structures of these compounds were identified and characterized using (TLC), infrared spectroscopy (FT-IR), 1H NMR data and microanalysis (CHN).Pharmacological study as anti-inflammatory activities for the final compounds were studied in rats by induced edema type of inflammation. Moreover, the results of a docking study of compounds III a-b into the COX-2 binding site revealed that its mechanism was possibly similar to that of naproxen, a COX-2 inhibitor. The effect of them on COX-2 antibody was showed it could significantly inhibit COX-2 activity.
