Newer indolyl imidazolones as anti-inflammatory agents.

Sixteen new 1,2-disubstituted-4-(indol-3'-yl)methylene imidazol-5-ones were synthesized by the condensation of oxazolone with different aryl amines and evaluated as to their anti-inflammatory and antiproteolytic activities. These derivatives showed 2-38% protection against carrageenin-induced paw oedema in albino rats at a dose of 100 mg/kg p.o. All compounds showed antiproteolytic activity. The degree of inhibition against trypsin-induced hydrolysis of casein ranged from 10 to 75% at a concentration of 4 X 10(-4) mol/l. Furthermore, active compounds of the series were also screened for their analgesic activity against aconitine-induced writhing in albino mice. The toxicity of the compounds was reflected by their approximate LD50 values.