Some novel pyrazolone derivatives as anti-inflammatory agents.

Synthesis of three series of compounds namely; 4-(phenazon-4-ylazo)-1-substituted thiocarbamoyl-3-methyl-5-pyrazolones (3-8), 4-(phenazon-4-ylazo)-1-substituted-3-methyl-5-pyrazolones (9-20) and 4-(phenazon-4-ylazo)-1-substituted-3,5-dimethylpyrazoles (21-31) was achieved. These compounds were subjected to anti-inflammatory investigation and it was found that compounds 9 and 10 exhibited a remarkable anti-inflammatory activity, of which the former was the most potent.