SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF NOVEL FUSED PYRAZOLES
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 Vilsmeierâ€“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.
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