Easy access to supramolecular gels of the nonsteroidal anti-inflammatory drug diflunisal: Synthesis, characterization, and plausible biomedical applications

Abstract

By exploiting salt formation, a new series of primary ammonium monocarboxylate salts of a nonsteroidal anti-inflammatory drug, namely, diflunisal, was synthesized. The majority of the salts thus synthesized turned out to be good gelators of various solvents, including the solvents (e.g., methyl salicylate and pure water) typically used for topical gel formulation. Single-crystal X-ray diffraction studies of a few gelator and nongelator salts in the series revealed details of the hydrogen-bonding networks present in the salts. Furthermore, one such gelator salt, namely, the diflunisal salt of serinol, was found to be biocompatible (MTT assay), and its anti-inflammatory (PGE₂ assay) response turned out to be as good as that of the parent drug, which is indicative of its potential in biomedical applications.