Reactions of phthalimides with 1-methylethylamine: analgesic and anti-inflammatory properties of resulting carboxamides.

The reaction of phthalimide derivatives (1a-c) with 1-methylethylamine in dimethylformamide (DMF) at room temperature afforded benzamido-N-prop-2-ynyl-2-(2-methylethyl)-carboxamide (3a), benzamido-N-cyclopentyl-2-(2-methylethyl)-car-boxamide (3b) and benzamido-N-benzyl-2-(2-methylethyl)-carboxamide (3c), respectively. In the carrageenan induced paw oedema test for anti-inflammatory activity, 3a (50 mg/kg) decreased the inflammatory response by 55% after 3 hrs while 3b and 3c exhibited significant reduction in the oedema level. The compounds 3a, 3b and 3c exhibited analgesic activities with 3b producing 76% inhibition. The activities were dose - dependent.