5-Chloro-ñET (code name PAL-526), or 5-chloro-AET, also known as 5-chloro-ñ-ethyltryptamine, is a serotonergic agent of the tryptamine and ñ-alkyltryptamine families. It is the derivative of ñ-ethyltryptamine (ñET or AET) with a 5-chloro substitution.
The drug is known to act as a potent serotonin releasing agent (SRA) and relatively weak serotonin 5-HT<sub>2A</sub> receptor near-full agonist. It shows negligible induction of norepinephrine and dopamine release but does act as a very weak dopamine reuptake inhibitor (DRI). 5-Chloro-ñET's and values are 33.2nM for serotonin release, 249nM ( = 87%) for serotonin 5-HT<sub>2A</sub> receptor agonism (7.5-fold lower than for serotonin release), 1,838nM for dopamine reuptake inhibition (55-fold lower than for serotonin release), and >10,000nM for norepinephrine release. The monoamine release assays were performed in rat brain synaptosomes.
Several close analogues of 5-chloro-ñET, including 5-chloro-ñMT and 5-fluoro-ñMT, are known to be potent monoamine oxidase inhibitors (MAOIs), specifically of monoamine oxidase A (MAO-A).
Analogues of 5-chloro-ñET include ñ-ethyltryptamine (AET), 5-fluoro-ñET, 5-chloro-ñMT, and 5-fluoro-ñMT, among others.
5-Chloro-AET was first described in the scientific literature by at least 1963.
5-Chloro-AET is not an explicitly nor implicitly controlled substance in Canada as of 2025.
5-Chloro-AET is not an explicitly controlled substance in the United States. However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.