Fluorescent Chalcone-Based Macrocyclic Crown Ether as a Multifunctional Platform for Dye Removal and Antibacterial...

A new chalcone-functionalized macrocyclic crown ether was synthesized as a highly functional scaffold, which combines supramolecular recognition, photophysical properties, environmental, and biological usage. The target compound was produced through a step-by-step approach and completely characterized through spectroscopic methods such as ¹H-NMR, ¹³C-NMR and DEPT-135 and Mass spectrophotometry. The addition of the chalcone moiety into the macrocyclic structure provided the system with specific fluorescence properties which were revealed broad π- π^* and intramolecular charge-transfer emission, with enhanced intensity governed by conjugation and macrocyclic rigidity. The material was found to have an effective adsorption capacity with respect to the representative organic dyes (methylene blue dye) in aqueous. The synthesized compounds demonstrated promising dye removal performance toward methylene blue under laboratory conditions, suggesting their potential applicability in future wastewater remediation studies. Host-guest interactions, π-π stacking, and electrostatic effects have been proposed in the studies of adsorption to be significant in the removal process. Simultaneously, the products possessed modest antibacterial effects on Gram-positive and Gram-negative strains Staphylococcus aureus and Escherichia coli. In an attempt to justify the detected biological activity, molecular docking experiments were conducted, which showed positive binding interactions between the chalcone unit and the target proteins, which confirms the experimental results. The concerted findings emphasize the benefit of incorporating a chalcone chromophore into a macrocyclic system of crowns ether to create a highly flexible system with synergistic structural and functional characteristics. These findings affirm the chalcone-based macrocyclic ethers as multifunctional scaffold with potential applications in the development of antibacterial, in wastewater remediation and photo functional materials.