Synthetic Methods of Quinoxaline Derivatives and their Potential Anti-inflammatory Properties.

Quinoxaline molecule has gathered a great attention in medicinal chemistry due to its vide spectrum of biological activities and emerged as a versatile pharmacophore in drug discovery and development. Its structure comprises bicyclic ring of benzopyrazine and displays a range of pharmacological properties including antibacterial, antifungal, antiviral, anticancer and anti-inflammatory. This review summarizes the different strategies for the synthesis of quinoxalines and their anti-inflammatory properties acting through different mechanisms. Structure activity relationships have also been discussed in order to determine the effect of structural modifications on anti-inflammatory potential. These analyses illuminate critical structural features required for optimal activity, driving the design and synthesis of new quinoxaline analogues with better anti-inflammatory activities. The anti-inflammatory properties of quinoxalines are attributed to their inhibitory action on expression of several inflammatory modulators such as cyclooxygenase, cytokines, nuclear factor kappa-light-chain-enhancer of activated B cells (NFB) and p38 mitogen activated protein kinase (p38 MAPK). Activators of nuclear factor erythroid 2-related factor 2 (NRF2) and agonistic effect on opioid receptors have also been discussed. Hence, this review may provide a future template for the design and development of novel quinoxaline derivatives acting through different molecular targets as potential anti-inflammatory agents with better efficacy and safety profile.