Solvent Free Synthesis: New 3-Acetyl Coumarin...

Solvent Free Synthesis: New 3-Acetyl Coumarin Derivatives Byknoevenagel Cyclization, Spectral Characterisation And Antimicrobial Evaluations

Author Name : Gajanan Dongare

DOI: https://doi.org/10.56025/IJARESM.2022.1062203

ABSTRACT

The new 3-acetyl coumarin derivatives was designed and synthesised in solvent free conditionby one pot method. The 3-acetyl-6-2H-chromen,6-bromo-3-acetyl-2H chromen-2-one, 6-nitro-3-acetyl-6-bromo-2H-chromen-2-one were synthesized separately by Knoevenagel cyclization of salicyldehyde, 5-bromosalicyldehyde, 5-nitrosalicyldehyde with ethylacetoacetate respectively.The structure of 3-acetyl coumarin derivatives was confirmed by elemental and spectral (viz.FT-IR, ¹H-NMR,¹³C-NMR and HR-Mass) techniques. The electronic transition spectra was recorded for the accounting the absorption property of chromophore groups. Further, compounds were screened for the antimicrobial studies against were screened for antibacterial activity against gram-negative bacteria (Escherichia coli and S. typhi), gram-positive bacteria (Staphylococcus aureus and Bacillus substillus) and the fungal activity against pathogens (Candida albicans andAspergillus niger) and obtained data show that all coumarinsviz., 3-acetyl-6-2H-chromen,6-bromo-3-acetyl-2H chromen-2-one, 6-nitro-3-acetyl-6-bromo-2H-chromen-2-one shows the promising microbial activity against Salmonella typhi, Escherichia coli, Bacillus substillis, Staphylococcus aureusbacterial and fungal strains.

Keywords: 3-acetyl coumarin, Knoevenagel reaction, Solvent free synthesis, Antimicrobial evaluations.