• N. Renuka University of Mysore
  • K. Ajay Kumar Post Graduate Department of Chemistry, Yuvaraja’s College, University of Mysore, Mysore 570005, India


Objectives: The aim of the present study was to synthesize a series of novel bridged pyrans as antimicrobial agents.

Methods: An isomeric mixture of 3-(4-ethoxy-10-methyl-8-oxo-2-phenyl-4,8-dihydro-2H-pyrano[3',2':6,7]chromeno[4,3-c]pyrazol-6-yl)-1-phenyl-1H-pyrazole-4-carbaldehydes, 2(a-f) and 3-(4-ethoxy-8-methyl-10-oxo-2-phenyl-4,10-dihydro-2H-pyrano[2',3':5,6]chromeno[4,3-c]pyrazol-6-yl)-1-phenyl-1H-pyrazole-4-carbaldehydes, 3(a-f) were synthesized by the reaction of 3,3'-(7-hydroxy-4-methyl-2-oxo-2H-chromene-6,8-diyl)bis(1-phenyl-1H-pyrazole-4-carbaldehyde) 1(a-f) and ethyl alcohol in the presence of conc. H2SO4. The synthesized compounds were evaluated for their antimicrobial activity.

Results: The structures of the new bridged pyran analogues 3-(4-ethoxy-10-methyl-8-oxo-2-phenyl-4,8-dihydro-2H-pyrano [3',2':6,7] chromeno [4,3-c]pyrazol-6-yl)-1-phenyl-1H-pyrazole-4-carbaldehydes, 2(a-f) and 3-(4-ethoxy-8-methyl-10-oxo-2-phenyl-4,10-dihydro-2H-pyrano [2',3':5,6] chromeno[4,3-c]pyrazol-6-yl)-1-phenyl-1H-pyrazole-4-carbaldehydes, 3(a-f) were confirmed by spectral studies and elemental analysis. The compounds 2e and 3e were having-CONH2 substitution and 2f and 3f were having-CSNH2 substitutions in the pyrazole rings showed antibacterial at minimum concentrations against all the tested organisms.

Conclusions: Results of the antimicrobial activity reveal that some of the synthesized compounds act as potential antimicrobial agents against different fungal and bacterial organisms.


Keywords: Antibacterial, Antifungal, Cyclisation, Formyl pyrazoles, Inhibitory


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How to Cite
Renuka, N., and K. A. Kumar. “STEREO SELECTIVE SYNTHESIS OF NOVEL PYRAZOLE AND COUMARIN APPENDED BRIDGED PYRANS AS ANTIMICROBIAL AGENTS”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 7, no. 11, Aug. 2015, pp. 69-73,
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