Thiophene is a five-membered heterocyclic compound containing a sulfur heteroatom with the molecular formula C4H4S. Thiophene is aromatic and is very similar to benzene; electrophilic substitution reaction is easier than benzene, and it is mainly substituted at the 2-position. Thiophene ring system has certain stability to oxidant.
Thiazoles are very important functional groups in medicinal chemistry. They act as ligands on a variety of biological matrices. Thiazoles are used in a wide range of therapeutic applications, such as antibacterial, antiretroviral, antifungal, antiallergic, antihypertensive, pain treatment, and to control symptoms of schizophrenia.
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.