Synthesis, Characterization and Biological Evaluation of Amino Acid Conjugates of Mefenamic Acid

Abstract

Mefenamic acid is used for its antipyretic, analgesic, antiinflammatory properties and also inhibits cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2) enzymes reversibly, which decreases production of pro-inflammatory prostaglandin precursors. Mefenamic acid suffers from the general side effects of non-steroidal antiinflammatory drugs, owing to presence of free carboxylic acid group. The study aimed to retard the adverse effects of gastrointestinal origin. Amino acid conjugates of mefenamic acid were synthesized by amidation with methyl esters of amino acids namely, phenylalanine, cysteine, glycine, lysine, arginine, valine, proline, serine, alanine and methionine. Synthesized conjugates were characterized by melting point, TLC, ¹H NMR and mass spectroscopy. Synthesized conjugates were also evaluated for their analgesic and antiinflammatory activities. Comparable analgesic and anti-inflammatory activities were obtained as compared to mefenamic acid.