An Overview of Pyridazine Derivatives: Various Approaches to Synthesis, Reactivity, and Biological Activity

Pyridazine derivatives have garnered considerable attention due to their remarkable chemical reactivity and extensive biological applications. This study presents a comprehensive review of recent advancements in the synthesis of pyridazine derivatives, with a focus on both conventional and innovative approaches (e.g., microwave and sonication), which include cyclocondensation, cycloaddition, addition, transition metal-catalyzed reactions, ring-opening and closure, coupling, nucleophilic cyclization, Knoevenagel condensation, hydrogenation, oxidation, aldol condensation, Diels-Alder, acylation, bromination, lithiation, and acid hydrolysis reactions. The distinctive characteristics of the pyridazine ring enhance its versatility in chemical reactions, facilitating its utilization in the synthesis of pharmacologically active compounds. Furthermore, the reactivity patterns are clearly delineated, emphasizing changes in functional groups and ring fusion strategies. This study examines the significant biological potential of pyridazine derivatives, encompassing antibacterial, antifungal, anticancer, anti-inflammatory, antiviral, antioxidant, antidiabetic, anticoagulant, analgesic, and cardiovascular properties. It aims to guide future research by identifying appealing structural motifs and synthesis pathways that may lead to the development of innovative medicinal molecules.