Synthesis and preliminary pharmacological evaluation of aminobenzensulfonamides derivatives of diflunisal as a anti-inflammatory agents

Objective: Synthesized of amino derivatives [4-aminobenzenesulfonamide, 4-amino-N-methylbenzenesulfonamide, or N-(4-aminophenylsulfonyl) acetamide] bound to carboxyl group of diflunisal, a well known nonsteroidal anti-inflammatory drugs (NSAIDs). and evaluation as a potential anti-inflammatory agent with expected selectivity against COX-2 enzyme.Design: Expermental studyResults: In vivo acute anti-inflammatory activity of the final compounds (13, 14 & 15) was evaluated in rat using egg-white induced edema model of inflammation in a dose equivalent to (50mg/Kg) of diflunisal. All tested compounds produced significant reduction of paw edema with respect to the effect of propylene glycol 50% v/v (control group). Moreover, compound (14) exhibited comparable anti-inflammatory activity to diclofenac (3mg/Kg), while compound (13) showed short duration of action, and compound (15) exhibited comparable effect to that of diclofenac with slower onset of action. Conclusion:The result of this study indicate that the incorporation of the 4-aminobenzenesulfonamide pharamacophore & its derivatives into diflunisal enhanced its anti-inflammatory activity& may increased its selectivity toward COX-2 enzyme which can be confirmed in future by assessing COX-2:COX-1 inhibitory ratio using whole blood assay.