Sydnone derivatives. Part VII: Synthesis of some novel thiazoles and theirpharmacological properties

The synthesis of some 4-(arylsydnonyl)-2-(4-arylhydrazono-3-methyl-5-oxo-2- pyrazolin-1-yl)-thiazoles by reacting 1-thiocarboxamido-3-methyl-4-(arylhyd razono)-2-pyrazolin-5-ones with different 4-bromoacetyl-3-arylsydnones is d escribed. A few compounds from this series were screened for their anti-inf lammatory, analgesic, and CNS depressant activities. Among the tested compo unds 6s, 6d, 6n, and 6u showed significant anti-inflammatory activity compa rable with that of standard drug lbuprofen. Compounds containing chlorine a nd carboxylic substituents are more active. 6f, 6r, and 6u showed marked an algesic activity and most of the compounds tested showed promising CNS depr essant activity comparable with that of standard drug pentobarbitone.