|Chemical and physical data|
|Molar mass||413.29 g/mol|
|3D model (Jmol)|
(–)-2β-Carboisopropoxy-3β-(4-iodophenyl)tropane (RTI-4229-121, IPCIT) is a stimulant drug used in scientific research, which was developed in the early 1990s. RTI-121 is a phenyltropane based, highly selective dopamine reuptake inhibitor and is derived from methylecgonidine. RTI-121 is a potent and long-lasting stimulant, producing stimulant effects for more than 10 hours after a single dose in mice which would limit its potential uses in humans, as it might have significant abuse potential if used outside of a medical setting. However RTI-121 occupies the dopamine transporter more slowly than cocaine, and so might have lower abuse potential than cocaine itself.
RTI-121 is mainly used in scientific research into the dopamine reuptake transporter. It is more selective for the dopamine transporter than other DAT radioligands such as β-CIT, and so has less nonspecific binding and produces "cleaner" images. Various radiolabelled forms of RTI-121 (with different radioactive isotopes of iodine used depending on the application) are used in both humans and animals to map the distribution of dopamine transporters in the brain.
RTI-121 is legal in all countries throughout the world as of 2007. Some jurisdictions such as the United States, Australia and New Zealand might however consider RTI-121 to be a controlled substance analogue of cocaine on the grounds of its related chemical structure.
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