Benzoxazole is an aromatic organic compound with a molecular formula of C7H5NO, a benzoxazole ring structure, and an odor similar to pyridine. Although benzoxazole itself has little practical value, many benzoxazole derivatives are commercially important. As heterocyclic compounds, benzoxazoles are used in research as starting materials for the synthesis of larger, often biologically active structures. Its aromaticity makes it relatively stable, although as a heterocycle it has an active site that enables it to be functionalized.
Cyclopropane is the smallest cyclic compound with unique structural features and physicochemical properties, which is widely used in the design of small molecule drugs. In drug design, it is often used to increase activity, fix conformation and improve PK and water solubility. The introduction of cyclopropyl groups into drugs can change various properties of molecules, such as improving metabolic stability; increasing biological activity; enhancing drug efficacy; limiting polypeptide conformation and slowing down its hydrolysis; reducing plasma clearance; improving drug dissociation and many more. Cyclopropane rings are widely found in marketed drugs, including cardiovascular drugs, central nervous system (CNS) drugs, anticancer drugs, autoimmune and anti-inflammatory drugs.