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.
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.
Cyclohexane is an organic compound with a chemical formula C6H12. It is a colorless liquid with a pungent odor, insoluble in water, and soluble in most organic solvents such as ethanol, ether, benzene, and acetone. Cyclohexyl fragments are a common structure in both natural and synthetic drugs. It can be used as both core structure and part of achiral side chain.