New substituted pyrazoles were prepared from o-hydroxyacetophenone and cinnamic acids as starting materials through1,3-diketones as intermediates. These intermediates on reaction with hydrazines in alkaline media, finally converted into corresponding pyrazoles. The synthesized compounds were characterized by their physical properties, IR, NMR and LC Mass spectroscopic studies. The antimicrobial activity of synthesized pyrazoles was assessed by agar cup method and filter paper disc method. In the most cases pyrazole having Chloro substitution on the styryl ring was found to be more efficient than the remaining against Xanthomonas Campestris and Aspergillus Niger species.
