Synthesis, Characterization and Biological Activities of New Pyrimidines and Pyrazoles Derivative

4-aminotoluidine on diazotization followed by coupling with ethylacetoacetate gave ethyl 2-[(4- methylphenyl) diazenyl]-3-oxobutanoate (2), which on condensation with substituted benzaldehydes in basic medium gave 1-[(4-methyl phenyl)diazenyl]-4-(substituted phenyl) but-3-en-2-ones (3a-e). The compound (3a-e) on reaction with urea in presence of alkali and ethanol afforded 4-(4-substituted phenyl)-6-{[(4-methylphenyl) diazenyl] methyl}- pyrimidin-2-ol (4a-e). Treatment of compound (3a-e) with hydrazine hydrate in presence of ethanol gave 5-(4- substituted phenyl)-3-{[(4-methyl phenyl) diazenyl] methyl}-4, 5-dihydro-1H pyrazole (5a-e). All newly synthesized compounds were characterized on the basis of IR, ¹HNMR and mass spectral data and evaluated for antimicrobial, analgesic activities.