Speaker
Description
This study reports the synthesis and antimicrobial evaluation of five chalcone derivatives bearing methyl, methoxy, and chlorine substituents. The compounds were synthesized via a modified Claisen–Schmidt condensation and characterized using proton and carbon-13 Nuclear Magnetic Resonance (¹H and ¹³C NMR), Mass Spectrometry (MS), and Infrared (IR) spectroscopy.
The in vitro antimicrobial activities of the synthesized chalcones were assessed by determining their Minimum Inhibitory Concentrations (MICs) against a panel of clinically relevant, drug-resistant pathogens: Methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae (ESBL+/fluoroquinolone-resistant), Escherichia coli (ESBL+/fluoroquinolone-resistant), Mycobacterium smegmatis (NCTC 8159), and Mycobacterium aurum (NCTC 10437). These pathogens were selected due to their clinical significance and availability.
The most active compounds featured chlorine and methoxy substituents, exhibiting MIC values as low as 6.25 µg/mL against MRSA, 12.5 µg/mL against E. coli, 50 µg/mL against both M. smegmatis and M. aurum, and 100 µg/mL against K. pneumoniae.
In conclusion, chalcones substituted with chlorine, methoxy, and methyl groups demonstrated promising antimicrobial activity against several multidrug-resistant pathogens. These findings suggest their potential as lead scaffolds for further development of antimicrobial agents targeting resistant bacterial infections.