5-chloro-αMT

5-Chloro-αMT

Clinical data
ATC code	None
Legal status
Legal status	Uncontrolled (but may be covered under the Federal Analogue Act in the United States and under similar bills in other countries)
Identifiers
IUPAC name 1-(5-Chloro-1H-indol-3-yl)propan-2-amine
CAS Number	712-07-2
PubChem CID	12833
ChemSpider	12303
Chemical and physical data
Formula	C11H13ClN2
Molar mass	208.687 g/mol
3D model (Jmol)	Interactive image
SMILES CC(Cc1c[nH]c2c1cc(cc2)Cl)N
InChI InChI=1S/C11H13ClN2/c1-7(13)4-8-6-14-11-3-2-9(12)5-10(8)11/h2-3,5-7,14H,4,13H2,1H3 Key:QMKOQSCXSYPIPB-UHFFFAOYSA-N

5-Chloro-α-methyltryptamine (5-Chloro-αMT), also known as PAL-542, is a tryptamine derivative related to α-methyltryptamine (αMT) and one of only a few known specific serotonin-dopamine releasing agents (SDRAs). It has been investigated in animals as a potential treatment for cocaine dependence. The EC₅₀ values of 5-chloro-αMT in evoking the in vitro release of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) in rat synaptosomes were reported as 16 nM, 54 nM, and 3434 nM, with an NE/DA ratio of 63.6 and a DA/5-HT ratio of 3.38, indicating that it is a highly specific and well-balanced SDRA. However, 5-chloro-αMT has also been found to act as a potent full agonist of the 5-HT_2A receptor, with an EC₅₀ value of 6.27 nM and an efficacy of 105%, and almost assuredly acts as a potent agonist of other serotonin receptors as well.

5-Chloro-αMT was found to not reliably produce intracranial self-administration in rats or substitute for cocaine in rats or monkeys. It was found through study of 5-chloro-αMT in rhesus monkeys that norepinephrine release has minimal influence on the abuse potential of monoamine releasing agents and that loss of norepinephrine release activity does not affect efficacy in reducing cocaine self-administration in SDRAs relative to serotonin-norepinephrine-dopamine releasing agents (SNDRAs) such as naphthylisopropylamine (PAL-287). However, SDRAs like PAL-542 would, in theory, be expected to produce fewer side effects (including sympathomimetic/cardiovascular effects, insomnia, hyperthermia, and anxiety) relative to SNDRAs, and thus would likely be comparatively more favorable in the treatment of cocaine dependence and other conditions.