Synthesis and pharmacological evaluation of carboxamides.

Some carboxamide derivatives with potential anti-inflammatory and analgesic properties were synthesized from the reaction of phthalimido alkyl acids with benzylamine at room temperature. All the compounds synthesized were unequivocally confirmed by means of Infrared, Nuclear Magnetic Resonance (1H and 13C), Mass spectrophotometer, and elemental analyses. The carboxamides were evaluated pharmacologically for their in vivo anti-inflammatory and analgesic activities by carrageenan-induced rat paw oedema and acetic acid-induced writhing test respectively. All the investigated compounds exhibited significant anti-inflammatory activity in the range of 45 to 70% in comparison to control. They showed promising analgesic activity at the dose used. 3-Benzamido-propionic acid -2-(N-benzyl)-carboxamide (4) exhibited the highest anti-inflammatory and analgesic activities and the effects were dose-dependent.