Synthetic Protocols and Applications of 1,2,5-Oxadiazoles: A Review

The 1,2,5-oxadiazole framework has garnered a lot of interest among many nitrogen heterocycles because of its capacity to give off NO under physiological circumstances. Because of this, major efforts by chemical scientists have been made to create novel drug possibilities in medicinal, material, and agriculture science that include the NO-donor 1,2,5-oxadiazole N-oxide subunit coupled to a known drug or a possible pharmacophore by C-C/C-N links or by using a suitable spacer. In the last few years, 1,2,5-oxadiazole and its derivatives have been reported as good pharmacophores as carbonic anhydrase inhibitors, antibacterial, vasodilating agents, antimalarial, anticancer, etc. In the presented manuscript, we reviewed granted patents (last 10 years), different synthetic strategies (last 27 years) of 1,2,5- oxadiazoles and their N-oxide derivatives synthesis such as cycloaddition, dimerization, cyclodehydration, condensation, thermolysis, nitration, oxidation, ring-conversion, etc. These synthetic methods have also been analyzed for their merits and demerits. The manuscript also highlighted various applications of 1,2,5-oxadiazole and its derivatives. We hope that researchers across the scientific streams will benefit from the presented review articles for designing their work related to 1,2,5-oxadiazoles.