6-APB

1-(1-benzofuran-6-yl)propan-2-amine

Overview

6-APB belongs to Entactogens/Empathogens / Phenethylamines.

Key safety note: 6-APB carries the serotonergic risks of an MDMA-like releaser: hyperthermia, serotonin toxicity (especially combined with other serotonergic drugs) and hyponatraemia (dangerously low blood sodium from drinking too much plain water).[2][3]
Effects
Subjective effects vary. What a substance feels like depends on dose, individual physiology, mindset, and setting. The points below describe commonly reported effects, not guaranteed, uniform, or desirable outcomes.
  • An MDA/MDMA-like entactogen: euphoria, emotional warmth, empathy and sociability with strong stimulant energy.
  • A mild psychedelic/visual component can appear, reflecting its serotonin-receptor agonism, though it is minor next to classic psychedelics.
  • Notably long-lasting (≈7–10 hours, with a drawn-out comedown and after-effects), longer than MDMA.
  • Common unwanted effects mirror MDMA: jaw tension, a raised heart rate and body temperature, anxiety and next-day fatigue.
Dosing & duration
Harm-reduction note: These are commonly cited reference ranges, not a recommendation or a “safe” dose. Potency, purity, body chemistry, tolerance, and drug combinations vary widely. Start low, go slow, wait for full effects before redosing, and never assume an unknown product matches these figures. Missing data is not evidence of safety.

Oral. Not a recommendation. 6-APB has never been studied in controlled human trials, so these are only commonly cited community ranges. It is more potent and much longer-lasting than MDMA which: together with its potent 5-HT2B-mediated cardiotoxicity and its hyponatraemia and serotonin-toxicity risks: makes redosing especially dangerous. It is usually handled as the succinate or hydrochloride salt. The succinate is heavier per mole, so a given mass of succinate delivers less active compound than the same mass of freebase or hydrochloride.

Dose ranges

Threshold

≈15 mg

Light

≈30–60 mg

Common

≈60–90 mg

Strong

≈90–120 mg

Duration

onset

≈30–60 min

peak

≈3–4 h

total

≈7–10 h

Chemical & Physical Properties
FormulaC11H13NO
Molar mass175.23 g/mol
StateSolid (usually the succinate or hydrochloride salt)
Melting pointNot reported
Boiling pointNot reported
DensityNot reported
Vapor pressureNot reported
pKaNot reported
LogP2.1 (predicted, XLogP3)
SolubilityNot reported
Refractive indexNot reported
Identifiers & Synonyms
CAS286834-85-3
CAS (enantiomer)
PubChem CID9794343
InChIKeyFQDAMYLMQQKPRX-UHFFFAOYSA-N
InChIInChI=1S/C11H13NO/c1-8(12)6-9-2-3-10-4-5-13-11(10)7-9/h2-5,7-8H,6,12H2,1H3
SMILESCC(CC1=CC2=C(C=C1)C=CO2)N

Synonyms

  • 6-APB
  • 6-(2-Aminopropyl)benzofuran
  • Benzofury
  • Benzo Fury
Pharmacodynamics & Biochemistry

6-APB (6-(2-aminopropyl)benzofuran) is a benzofuran entactogen, a positional isomer of 5-APB and the benzofuran analogue of MDA, best known as the main compound sold as 'Benzo Fury'. It acts as a serotonin–noradrenaline–dopamine releasing agent with balanced, potent release of all three monoamines (release EC50 ≈36 nM serotonin, ≈14 nM noradrenaline, ≈10 nM dopamine in rat brain synaptosomes), producing MDA/MDMA-like entactogenic and stimulant effects. It is also a direct serotonin-receptor agonist. Its highest-affinity target is 5-HT2B (Kᵢ ≈3.7 nM, agonist EC50 ≈140 nM, Emax ≈70%). It also has moderate 5-HT2C affinity (Kᵢ ≈270 nM), weak partial 5-HT2A agonism (EC50 ≈5,900 nM, Emax ≈43%), 5-HT1A affinity (Kᵢ ≈1,500 nM), α2C-adrenergic affinity (Kᵢ ≈45 nM) and rodent TAAR1 activity. As a reuptake inhibitor it is much weaker (NET Kᵢ ≈117 nM, DAT ≈150 nM, SERT ≈2,700 nM), so its transporter action is dominated by release. Its potent, high-affinity 5-HT2B agonism is the central safety concern: chronic 5-HT2B activation drives cardiac valve disease, as seen with fenfluramine and (with heavy use) MDMA, so repeated 6-APB use is expected to carry a serious cardiotoxic (valvulopathy) risk.

Biological targets

  • SERT
  • NET
  • DAT
  • 5-HT2B
  • 5-HT2C
  • 5-HT2A

Binding & functional measurements

TargetMeasurementSpecies
Serotonin transporterEC50 36 ± 5.0 nM
Emax 100%		Rat
Noradrenaline transporterEC50 14 ± 2.0 nM
Emax 98%		Rat
Dopamine transporterEC50 10 ± 1.0 nM
Emax 101%		Rat
5-HT2BKi 3.7 nMHuman
5-HT2CKi 270 nMHuman
5-HT2AEC50 5,900 nMHuman
5-HT1AKi 1,500 nMHuman
TAAR1Unspecified Binds rodent TAAR1 (qualitative)Rodent
Pharmacokinetics
BioavailabilityOral
TmaxNot well characterised (onset ≈30–60 min)
Half-lifeNot established in humans (duration ≈7–10 h)
VdNot reported
Protein bindingNot reported
MetabolismHepatic (Phase I furan-ring hydroxylation/cleavage, Phase II glucuronidation)
ExcretionRenal (presumed)
Toxicology & Safety
Harm-reduction note: Toxicity and risk depend on dose, route, purity, combinations, setting, and individual health factors. Missing harms should never be interpreted as evidence of safety.

Not reported

6-APB carries the serotonergic risks of an MDMA-like releaser: hyperthermia, serotonin toxicity (especially combined with other serotonergic drugs) and hyponatraemia (dangerously low blood sodium from drinking too much plain water). Its long duration (≈7–10 h, with after-effects up to ~24 h) strongly encourages redosing and overexertion. Acute psychosis has been reported with recreational use, including in combination with synthetic cannabinoids (e.g. JWH-122). The most distinctive concern is its potent, high-affinity 5-HT2B agonism, which, as with fenfluramine and MDMA, is expected to damage heart valves (valvulopathy) with repeated use. It has never been tested in controlled human trials and its safety margin is unknown. Missing data must never be read as evidence of safety.[2][3]

Legal Status
Legal note: Legal status can change over time and may vary by country, region, formulation, analogue status, prescription context, and enforcement practice. Always confirm with current official sources before relying on this section.
Interactions & Contraindications

Drug interactions

MAOIs Serotonin toxicity, potentially life-threatening.[2]
SSRIs, SNRIs, Other serotonergic drugs Serotonin-toxicity risk, other releasers included.[2]
Stimulants (amphetamines, cocaine) Additive cardiovascular strain.[2]
Synthetic cannabinoids Acute psychosis reported in combination (e.g. JWH-122).[2]
Excess plain water (without electrolytes) Excess plain water without electrolytes carries a hyponatraemia risk, as with MDMA.[2]

Contraindications

Cardiovascular disease, hypertension or arrhythmia[3]
Pre-existing heart-valve disease 5-HT2B-mediated valvulopathy risk.[3]
Concurrent MAOI, SSRI/SNRI or other serotonergic medication concurrent MAOIs or serotonergic medication.[2]
Personal or family history of psychosis, schizophrenia or bipolar disorder[2]
Pregnancy or breastfeeding
Usage & Context
  • Emerged as a 'legal high' / designer drug around 2010, sold as 'Benzo Fury' (pellets or powder) and marketed as an MDMA substitute, often alongside its isomer 5-APB.
  • Originally described in 2000 in an Eli Lilly patent as a candidate 5-HT2C agonist. Adopted recreationally before being banned across many countries.
Sources & Evidence

Further Information