A Comprehensive Review of Carbazole Based Heterocyclic Hybrids in Multi Target Drug Design

Abstract

The growing prevalence of multifactorial diseases such as Alzheimer’s disease, cancer, diabetes, microbial infections and inflammatory disorders has highlighted the limitations of the conventional one drug one target therapeutic approach. As a result, multi target directed ligands (MTDL) have become a viable tactic for concurrently modifying several pathogenic pathways implicated in development of disease. Because of the tricyclic aromatic structure, favourable lipophilicity, ease of functionalization and variety of pharmacological actions, carbazole has gained significant attention among the several heterocyclic scaffolds investigated in medicinal chemistry. The carbazole nucleus is a desirable platform for hybrid drug discovery because of its exceptional neuroprotective, antioxidant, anticancer, antibacterial, anti-inflammatory and antidiabetic properties. This review highlights recent advances in the development of carbazole based heterocyclic hybrids as multifunctional therapeutic agents. Various molecular hybridization strategies involving carbazole conjugation with pharmacologically relevant scaffolds such as tacrine, stilbene, quinolinium, chromene, indole, pyridine, triazole, quinoline and pyrazoline are discussed. The influence of linker architecture, electronic modifications and substitution pattern on biological activity is also examined. The findings demonstrate that carbazole-based hybrid design can effectively interact with multiple biological targets and offering enhanced efficacy, reduced toxicity and improved pharmacological profiles. Overall, carbazole based heterocyclic scaffold represent a versatile and promising class of compounds for the development of next generation therapeutics aimed at the management of complex diseases.