Pyrrolidine, also known as tetrahydropyrrole, is a saturated five-membered heterocyclic ring, which is miscible with water. Pyrrolidine exists in many alkaloids and drug molecules, such as kappa opioids, antagonists of dopamine D4 receptors, and HIV reverse transcriptase inhibitors.
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.