Unique Azolyl Acylhydrazonyl Hybridization of Aloe Emodins to Access Potential Antibacterial Agents

Comprehensive Summary A type of unique azole‐hybridized acylhydrazonyl aloe emodins (AAEs) were developed as new antibacterial agents for combating bacterial infections. Some target AAEs showed strong antibacterial activities, especially, tetrazolylthioether AAE 27a exhibited broad antibacterial spectrum with 16—256 folds and 8—64 folds more active antibacterial efficacy than the reference drugs aloe emodin and norfloxacin, respectively. Tetrazolylthioether AAE 27a also gave low hemolysis and cytotoxicity, as well as favorable bioavailability. Preliminary mechanism explorations revealed that tetrazolylthioether AAE 27a could cause bacterial membrane depolarization and damage the cell membrane, resulting in nucleic acid leakage. Moreover, compound 27a could intercalate into DNA to impede its replication and form supramolecular 27a ‐DNA gyrase complex to disturb the function of DNA gyrase. These findings would provide valuable insights for the further exploration of azolyl acylhydrazonyl aloe emodins as new potential antibacterial candidates.