Synthesis of Fluorescent Calix[4]arene Derivatives for the Detection of Hg(II) / Cr(VI) and Investigation of their Antimicrobial Properties

Abstract

Calixarenes are noteworthy compounds in organic chemistry since they can be synthesized and modified more conveniently compared to many other supramolecules. They can undergo functionalization either through the phenolic–O groups or at the para-position of the phenolic rings. Moreover, substitutions at the upper and lower rims allow their conversion into various derivatives, including ethers, esters, carboxylates, and amides. Owing to these features, calixarenes have become valuable supramolecular platforms in areas such as molecular recognition, sensing, self-assembly, catalysis, biocatalysis, nanotechnology, and drug discovery. Their unique structural characteristics also provide opportunities for biomedical applications, particularly in the development of antitumor, antiviral, antimicrobial, antithrombotic, and antifungal agents. In the present study, 4-sulfo-1,8-naphthalimide derivatives of calix[4]arene were synthesized, followed by the replacement of potassium sulfonate salts with silver ions to obtain silver sulfonate salts. The resulting antimicrobial materials were used to form transparent biofilms in the presence of hyaluronic acid (HA), and their antimicrobial activity was subsequently evaluated.