Recent advances in the synthesis of nitrogen-containing heterocyclic compounds via multicomponent reaction and their emerging biological applications: a review

Nitrogen-containing heterocyclic compounds (NCHCs) have an important role in the field of medicinal chemistry due to their extensive biological activities and their prevalence in natural compounds, pharmaceuticals, and materials science. Here, we have reviewed the recent advancements in the formulation of NCHCs via multicomponent reactions (MCRs). These reactions, which allow the efficient and eco-friendly formulation of complex molecules, have revolutionized the synthesis of heterocycles such as triazoles, imidazoles, pyrazoles, pyrimidines, and pyridazines. This review has further emphasized the key MCR strategies, including the Biginelli, Ugi, Hantzsch, and Passerini reactions, highlighting their mechanisms, scope, and applications in drug discovery. Finally, we have emphasized the biological evaluation of synthesized NCHCs possessing several pharmacological features like antiallergic, anti-inflammatory, anticancer, antimicrobial, neurological, and analgesic activities. The synthesis of specific NCHC scaffolds and their structure–activity relationships are also explored, emphasizing the significance of these compounds in the development of novel therapeutics.