Design, Synthesis, and Antimicrobial Evaluation of Novel Chalcone-based Derivatives of Gallic Acid.

INTRODUCTION

The global rise in antimicrobial resistance highlights the urgent need for new therapeutic agents. This study investigates chalcone-based derivatives of gallic acid as potential antimicrobial compounds.

METHODS

Chalcone derivatives (2a-4c) were synthesized via methylation, Grignard reaction, Claisen-Schmidt condensation, and cyclization. Structural confirmation was achieved using FTIR, NMR, and mass spectrometry. The Docking studies were performed against HSP90α (PDB ID: 1UY6), and ADME properties were predicted using QikProp. Antimicrobial activity was assessed using microbroth dilution and agar well diffusion methods against S. aureus, E. coli, K. pneumoniae, A. baumannii, and C. albicans.

RESULTS

Compounds 2d and 3c showed the strongest docking interactions with HSP90α, outperforming ciprofloxacin. MIC results indicated that 2d was most effective, with values as low as 0.39 μg/ml for E. coli and C. albicans. Other compounds, such as 3c and 4c, also showed significant activity (MIC 0.78-6.25 μg/ml). ADME profiling predicted high oral absorption and favorable drug-like properties for the most active compounds.

DISCUSSION: Electron-withdrawing groups enhanced antimicrobial activity and binding affinity. Docking data supported the in vitro results, revealing key interactions within the HSP90α active site.

CONCLUSION

Chalcone derivatives, particularly 2d, show promise as broad-spectrum antimicrobial agents. Their structural and pharmacokinetic profiles support further development for therapeutic use.