Published Paper Details:

Quinoxaline and its fused heterocyclic derivatives constitute an important class of nitrogen-containing heterocyclic compounds possessing remarkable chemical versatility and extensive biological activities. Owing to their electron-deficient aromatic framework and facile functionalization, quinoxaline derivatives have attracted considerable attention in medicinal chemistry, pharmaceutical sciences, and synthetic organic chemistry. The present review summarizes the chemistry, synthetic methodologies, structural modifications, and pharmacological significance of quinoxaline derivatives reported over the years. Various synthetic approaches including condensation of o-phenylenediamines with 1,2-dicarbonyl compounds, intramolecular cyclization reactions, ring contraction methods, and synthesis of quinoxaline-N-oxides have been discussed systematically. Particular emphasis has been placed on the diverse biological applications of quinoxaline analogues such as antibacterial, antifungal, antiviral, anticancer, anti-inflammatory, antituberculosis, anti-HIV, antidepressant, and antiglaucoma activities. Structure-activity relationship studies reveal that substitution patterns and fused heterocyclic systems significantly influence biological potency. In addition, recent developments in fused quinoxaline systems and their pharmaceutical relevance are highlighted. This review demonstrates that quinoxaline derivatives remain promising scaffolds for the development of novel therapeutic agents and functional organic materials.