Pathogenic bacteria, with their innate resistance to drugs, pose a constant threat to human health and well-being and put a persistent strain on the health care system. Development of more effective and safer novel antibacterial drugs is warranted to counter the menace unleashed by pathogenic bacteria. Integration of privileged pharmacophores from various bioactive molecules into a single template is a promising strategy to obtain new leads with unique mechanisms of action to overcome drug resistance. In the past few years, numerous isatin-based hybrid molecules were screened and their pharmacological properties were explored in efforts to develop novel therapeutics. The results of screening show that isatin conjugates exhibit promising activity against a broad range of highly pathogenic gram-positive and gram-negative bacteria and can serve as important leads in the discovery of highly potent broad spectrum antibacterial drugs. Herein, we review the antibacterial bioactive profile of a variety of hybrid isatin derivatives, including isatin–azole, isatin-quinoline/ quinolone, isatin-furan/coumarin, isatin-hydrazone/(thio)semicarbazone, isatin dimers, and isatin– indole hybrids.
Keywords: Isatin, molecular hybridization, hybrid compounds, antibacterial agents, drug resistance, structure–activity relationship (SAR)