• Pavithra Gurunanjappa University of Mysore
  • Renuka Nagamallu University of Mysore
  • Ajay Kumar Kariyappa UNIVERSITY OF MYSORE


Objective: The aim of the present work was to synthesize fused pyrazoles and examine them for their in vitro antimicrobial activity.

Methods: The formyl pyrazoles were synthesized by Vilsmeier–Haack reaction from o-hydroxy acetophenone hydrazones. The pyrazoles on oxidative cyclisation in the presence of ethanol and catalytic amount of H2SO4 yielded pyrano [4,3-c] pyrazoles. The structures of the synthesized derivatives were confirmed by Mass, 1H NMR and elemental analysis. The synthesized new pyranopyrazoles were screened for their antimicrobial activity by broth dilution technique.

Results: The results of the antimicrobial assay revealed that the compound 4b having chloro substitution showed good activity against different microorganisms tested.

Conclusion: It is noteworthy that the compounds synthesized by a simple and accessible procedure leads to a molecules of promising antimicrobial activity.


Keywords: Antimicrobial, Hydrazones, MIC, Vilsmeier–Haack reagent


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Author Biography

Ajay Kumar Kariyappa, UNIVERSITY OF MYSORE


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How to Cite
Gurunanjappa, P., R. Nagamallu, and A. K. Kariyappa. “SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF NOVEL FUSED PYRAZOLES”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 7, no. 2, Dec. 2014, pp. 379-81,
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