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.
Thiazolopyrimidines are important analogs of purines. Thiazolopyrimidine derivatives have various pharmacological properties, including antiviral, antitumor, antibacterial, and antihypertensive effects.