Supramolecule-Driven Host–Guest Co-Crystallization of Cyclic Polyphenols with Anti-Fibrotic Pharmaceutical Drug

Host–guest complexes are of interest as supramolecular drugs in pharmaceutical sciences because the activity of antibacterial agents can be enhanced upon complexation with various cyclic oligomers or metal ions, with some complexes possessing higher healing properties than the parent drugs. Herein, to develop a microbiologically potent supramolecular drug, we investigated the complexation of macrocyclic hosts (resorcinarenes and β-cyclodextrin) with pirfenidone (PFD), an FDA-approved antifibrotic drug containing an antibacterial pyridone core. Electronic structure calculations gave insights into the interactions in the host–PFD complexes. Further, complex formation and clinical activities were investigated using spectroscopic techniques and in vitro measurements of antibacterial activity against Gram-positive and Gram-negative bacteria. An unprecedented interplay between the antibacterial activity of the polyphenolic resorcinarene hosts and their ability to interact chemically with PFD was found to improve the overall antibacterial activity of PFD. These results could revolutionize the use of synthetically modifiable resorcinarene and their analogues for fine-tuning the clinical behavior of drugs.