Structure: Mechanistic Studies and Pharmacological Importance of Oxadiazole Derivatives and Allied Oxygen Heterocycles

Oxadiazole is a five-membered heterocyclic compound containing two carbon, two nitrogen, and one oxygen atom in the ring. 1,3,4-oxadiazole is widely investigated because of its significant interacting potential with distinct binding sites in the biological systems.A range of 2-substituted phenyl -1, 3, 4-oxadiazole-2- thion derivatives(2) of pharmacological interest have been synthesisized from substituted carboxylic acids (1). Pyridine carboxylic acids (3) have also been transformed to 5-pyridyl-1, 3, 4-oxadiazole-2-thion derivatives (4) in excellent yields. Ɣ-lactones are oxygen containing heterocycles extensively distributed in nature and display a broad spectrum of biological activities.Avariety of gama lactones have been generated from epoxides and esters .Oxygen heterocycles of the type (6) possessing antitumor properties have been obtained from alkenyl ketones in high yields. Mechanistically interesting NBS mediated cyclisations of two delta-alkenyl ketones, (7) and (8) have been employed to afford stereoisomer’s (9) and (10). This article presents newly developed mechanisms for the construction of a range of oxadiazole derivatives and allied oxygen heterocycles. Recent applications of pharmacological importance of these compounds have also been added.