Montmorrilonite K10 catalyzed efficient synthesis of some 4'-nitrochalcones and their 1, 3, 5-triaryl-2-pyrazolines and in vitro antimicrobial evaluation

Abstract

An expeditious synthesis of some 4´-nitrochalcones (3a-n) and their subsequent facile one-pot transformation to 1, 3,<br />5-triaryl-2-pyrazolines (4a-n) has been carried out using montmorrilonite K10 via microwave mediated solvent free protocol.<br />An emphasis is given to highlighting the greenness of the processes, and a fair comparison is also provided between different<br />inorganic solid supports as catalysts. Both conventional as well as non-conventional approaches have been explored by<br />comparing the reaction conditions and yields. The newly synthesized pyrazolines were studied for their in vitro antimicrobial<br />evaluation against bacterial strains Bacillus pumilus and Escherichia coli and fungal strains Aspergillus niger and Penicillium<br />chrysogenum. Findings of biological evaluation highlighted 4b, 4e, 4j and 4m as potential new leads in the search of new<br />antimicrobial agents. The structures of newly synthesized compounds have been established on the basis of elemental analysis<br />and spectroscopic studies.