Synthesis and Characterisation of Some New Pyrazole Analogues for Antimicrobial Activity

Several pharmacological activities like antitubercular, analgesic, anti-cancer, anti-inflammatory, antiasthmatic, antioxidant and antibacterial activities have been attributed to pyrazoles. The above observations prompted us to synthesize some novel pyrazole derivatives as possible antimicrobial agents. A series of novel 1,3,5-trisubstituted pyrazole derivatives (P1-P15) have been synthesized by the reaction of substituted chalcones (C1-C15) with succinichydrazide. The starting material, chalcones were prepared by claisen Schmidt condensation of acetophenone with aldehydes in the presence of sodium hydroxide in ethanol. Succinichydrazide was synthesized by condensing succinic acid with hydrazine hydrate. The cycloaddition of chalcones with succinichydrazide gives 1,3,5-trisubstituted pyrazole derivatives. The structures of synthesized derivatives were confirmed by IR, 1HNMR and Mass spectrum. The synthesized compounds were screened for their antibacterial and antifungal activity. The antibacterial activity data of the synthesized derivatives revealed that the compound P4, P13 and P7, P14 were effective against gram positive and gram negative organisms respectively. The antifungal activity data revealed that the compound P7 and P8 showed good activity against tested fungi.