Open Access Articles- Top Results for PRL-8-53


Systematic (IUPAC) name
Methyl 3-[2-[benzyl(methyl)amino]ethyl]benzoate
Clinical data
  • US: N (Not classified yet)
  • Unscheduled
51352-87-5 (HCl)
PubChem CID 39988
Chemical data
Formula C18H21NO2
283.36 g/mol

PRL-8-53 is a nootropic research chemical derived from benzoic acid and phenylmethylamine (Benzylamine) that has been shown to act as a hypermnesic drug in humans; it was first synthesized by medical chemistry professor Nikolaus Hansl at Creighton University in the 1970s as part of his work on amino ethyl meta benzoic acid esters.[1][2]

Nootropic effects

A single study in humans was reported in 1978. The double-blind trial of PRL-8-53 in 47 healthy volunteers measured its effects on a variety of cognitive measures. 5 mg of the drug was administered orally 2–2.5 hours before the study tasks.[1] Subjects were given 12-item word lists to memorize as part of the trial. While initial word acquisition performance on PRL-8-53 was only 107.46% of baseline, subjects recalled words at 132.5–142.7% of the baseline rate 24 hours after testing, and at 145.2–146.2% after a week. Stronger effects were noted in the bottom 60% of subjects (who recalled 6 or fewer words on placebo at 24h), with 24-hour retention improved to 187.5–191% of baseline, and one week retention to 200–205%. Subjects over 30 displayed even more substantial results, with improvements to 208–222% and 236–252% of baseline performance at one day and one week respectively.[1] Both visual reaction time and fine motor control improved to a statistically insignificant degree.[1] No side effects were reported during the trial.[1]

Mechanism of action

The exact mechanism of action of PRL-8-53 remains unknown. It does not display stimulant properties, and does not potentiate dextroamphetamine.[citation needed] It displays cholinergic properties, and potentiates dopamine while partially inhibiting serotonin. PRL-8-53 reverses the catatonic and ptotic effects of reserpine.[1][3]


PRL-8-53 is relatively non-toxic, with an oral LD50 in mice of 860 mg/kg, giving the drug a high therapeutic index. Doses above 8 mg/kg have brief hypotensive effects in the canine. High doses depress motor activity in the rat and mouse, with the ED50 for a 50% reduction in motor activity of mice at 160 mg/kg. PRL-8-53 displays spasmolytic effects.[3]


Methyl 3-(2-(benzylmethylamino)ethyl)benzoate hydrochloride
3-(2-benzylmethylaminoethyl) benzoic acid methyl ester hydrochloride
3-(2-(Methyl(phenylmethyl)amino)ethyl)benzoic acid methyl ester hydrochloride

See also


  1. 1.0 1.1 1.2 1.3 1.4 1.5 Hansl, NR; Nikolaus R. Hansl, Beverley T. Mead (1978). "PRL-8-53: Enhanced learning and subsequent retention in humans as a result of low oral doses of new psychotropic agent". Psychopharmacology 56 (3): 249–253. PMID 418433. doi:10.1007/BF00432846. 
  2. US Patent 3870715 A: Substituted amino ethyl meta benzoic acid esters
  3. 3.0 3.1 Hansl, N. R. (1974). "A novel spasmolytic and CNS active agent: 3-(2-benzylmethylamino ethyl) benzoic acid methyl ester hydrochloride". Experientia 30 (3): 271–272. PMID 4824605. doi:10.1007/BF01934822.  edit