Synthesis and Biological Evaluation of Fused Pyrans Bearing Coumarin Moiety as Potent Antimicrobial Agents


Nagamallu Renuka and Kariyappa Ajay Kumar

Post Graduate Department of Chemistry, Yuvaraja’s College
University of Mysore, India
corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.




A simple approach for the synthesis of fused pyrans to coumarin moiety is presented. The intramolecular cyclisation of 1-aryl-3-(7-hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)-1H-pyrazole-4-carbaldehydes under reflux conditions at 80ºC afforded fused pyrans in a relatively good yield. The synthesized compounds were characterized by spectral studies and elemental analysis. The new compounds were evaluated in vitro for their antifungal and antibacterial activity against different fungi and bacterium species.



The growing population of antibiotic resistance of bacteria strains as a result of enzymatic inactivation of the drug, modification of target sites and extrusion by efflux has become one of the major tasks to be addressed in the area of research in drug design and discovery (Spratt 1994). The construction of complex molecular architectures that exhibit greater biological potency in a facile and efficient manner remains an overarching goal for chemists. In the recent years, coumarins have attracted great attention because of their synthetic utility as building blocks for the construction of biologically potent molecules. Coumarin derivatives are known to have a wide range of activities such as antioxidant, antimicrobial, anti-HIV, antibiotic, anticancer, muscle relaxant, anti-inflammatory and anticoagulant properties (Murakami et al., 2000).
Pyrazoles have attracted particular interest over the last few decades due to use of such a ring system as the core nucleus in various drugs. This class of compounds represent a key motif which occupy a prime place in medicinal chemistry due to their competence to exhibit antimicrobial (Gilbert et al., 2006), anticancer (Igor Magedov et al., 2007), anti-inflammatory (Nora Bennamane et al., 2008), anticonvulsant ( Ozdemir et al., 2007), antipyretic (Sener et al., 2002), peptide deformylase . . . . . [DOWNLOAD FULLTEXT HERE]



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