Benzothiophene is an aromatic organic compound with the molecular formula C8H6S and a naphthalene-like odor. Benzothiophenes are used in research as a starting material for the synthesis of larger, often biologically active structures. It exists in medicinal chemical structures such as raloxifene, zileuton, and sertaconazole, and can also be found in BTCP. It is also used to make dyes such as thioindigo.
Incorporation of heterocycles into drug molecules can enhance physical properties and biological activity. Oxadiazoles are a class of five-membered heterocycles containing one oxygen and two nitrogen atoms with special biological activity and thermodynamic properties. 1,2,4- and 1,3,4-oxadiazoles are widely used in the development of bioactive molecules, but 1,2,5-oxadiazoles (furazans) are used relatively sparingly. Compared with 1,2,4- and 1,3,4-isomers, 1,2,5-oxadiazole has unique physicochemical properties and electronic effects. The furazan ring has a strong inductive effect, comparable to that of trifluoromethyl or tetrazolyl. The unique properties of furoxan can confer specific pharmacological activities to drug-like molecules.