1,2-Benzoisoxazole is an aromatic organic compound with the molecular formula C7H5NO containing a benzene-fused isoxazole ring structure. The compound itself has no general application; however, functionalized benzoxazoles and benzoisoxazoles have a variety of uses, including therapeutic drugs such as some antipsychotics (including risperidone, paliperidone, cape ketone and iloperidone) and the anticonvulsant azolamide.
Oxirane is a three-membered ring compound consisting of one oxygen atom and two carbon atoms. Oxirane is present in natural products such as cryptocin, which has anticancer properties, and azidomycin, trienone, and epoxidomycin, which have shown activity against drug-resistant leukemias and AIDS-related lymphomas. Other oxirane containing bioactive molecules have anti-inflammatory, immunosuppressive, and antitumor activities. Oxiranes are a strained ring susceptible to various nucleophilic, ring-opening or rearrangement reactions, so they are considered to be one of the most important intermediates in organic synthesis.