RESEARCH MONOGRAPH · KDC-MN-336

Pinoline

May 9, 2026 Kodiac biolabs Research Revised May 30, 2026 2 min read

Our opinion on this compound

42/100

Endogenous beta-carboline with intriguing pineal biology and a thin evidence base we cant get past

Honestly, pinoline is one we havent put serious bench time into and the literature is too thin to have a strong opinion. The story is real but underdeveloped.

Pinoline is 6-methoxy-1,2,3,4-tetrahydro-beta-carboline, a beta-carboline endogenously formed by condensation of 5-methoxytryptamine with formaldehyde in the pineal gland. Callaway's papers in the 90s suggested it might be biosynthesized at low levels in pineal tissue alongside melatonin and that it could function as a weak reversible MAO inhibitor and possible psychoactive modulator. The mechanism story has always been adjacent to the 'pineal DMT' hypothesis that Strassman's work made famous, but pinoline isnt DMT and the actual evidence for it being meaningfully psychoactive on its own is essentially zero.

What's actually known: it's a reversible MAO-A inhibitor at micromolar concentrations, which is much weaker than harmaline or harmine. Some in vitro evidence for serotonin reuptake inhibition. Some antioxidant activity that's been emphasized by groups like Pahkla and Maharaj in older papers. Theres also occasional speculation that it could potentiate endogenous tryptamines if both were present in sufficient concentrations, but the kinetic and concentration arguments for that actually happening at meaningful levels in vivo are weak.

The biological-existence question is itself partly unresolved. Some groups have detected pinoline in pineal extracts, others have struggled to replicate at meaningful concentrations. Whether it's a real endogenous neuromodulator or a low-level byproduct of tryptamine biosynthesis is honestly not settled.

For research it's available from a few specialized suppliers as a synthetic small molecule, HPLC verification is straightforward (it's a simple beta-carboline scaffold). Cost is moderate. If you're doing beta-carboline structure-activity work or pineal biology it has a niche. Outside that the use case is unclear.

What we like is the genuine novelty of the biology, if any of the pineal-modulator story turns out to be real at meaningful levels.

What we dont like is how much of the popular framing of pinoline (often as a 'serotonin booster' or 'natural MAO inhibitor') outruns the actual evidence by a wide margin.

Curious compound, thin literature, hold opinions loosely. Worth following if the pineal-biology field generates new tools.

Evidence: 25
Mechanism: 40
Reliability: 30
Safety: 65
Sourcing: 55
Value: 50
Signal: 35
Staying power: 35

Plain-language summary Intrigue 40 / 100

Pinoline is a methoxylated tetrahydro-beta-carboline that the body makes endogenously, found in pineal gland and brain tissue. Biosynthetically it sits between the tryptamines (DMT, 5-MeO-DMT) and melatonin, which has fueled the long-disputed hypothesis that the pineal gland produces endogenous psychedelic compounds (the so-called DMT-pineal theory associated with Rick Strassman). Pharmacologically it is a weak reversible MAO-A inhibitor and a weak serotonin reuptake inhibitor. Concrete physiological function remains speculative, with most claims resting on tissue distribution and conjecture rather than controlled human studies. Not stocked by Kodiac. This monograph is provided for research and educational reference.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Endogenous beta-carboline (6-methoxy-tetrahydro-beta-carboline)

An endogenous methoxylated tetrahydro-beta-carboline; a methylated tryptamine derivative implicated in pineal gland function.

Abstract

Pinoline (6-methoxy-1,2,3,4-tetrahydro-beta-carboline, 6-MeO-THBC; CAS 20684-89-1; molecular formula C12H14N2O; molecular weight 202.25) is an endogenous beta-carboline alkaloid identified in pineal gland and brain tissue. The compound is biosynthetically related to melatonin and to the tryptamines (DMT, 5-MeO-DMT) and is hypothesized to participate in endogenous psychoactivity (the contested DMT-pineal hypothesis). Pharmacologically, pinoline is a weak reversible MAO-A inhibitor and a serotonin reuptake inhibitor; the in vivo concentrations are low and its physiological role is incompletely characterized. Plasma half-life and pharmacokinetics in humans are sparsely documented. Used as a research probe for endogenous beta-carboline chemistry and pineal-gland-derived signaling.

Mechanism of action

Endogenous beta-carboline; weak reversible MAO-A inhibition and serotonin reuptake inhibition. Pineal-gland-associated tryptamine derivative.

Reported research dose ranges

Sparse pharmacokinetic data; research dosing is exploratory.

References

Airaksinen MM, Kari I. Beta-carbolines, psychoactive compounds in the mammalian body. Med Biol 1981.
Callaway JC. Some chemistry and pharmacology of pinoline. J Psychoactive Drugs 1988.
Pahkla R, et al. Comparison of the antioxidant activity of melatonin and pinoline in vitro. J Pineal Res 1998.

Read the full monograph

The full reference document is available as a research-use-only PDF download. Note: PDFs for newly added compounds may take a few hours to propagate after this article was published.

KDC-MN-336

The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.

Download PDF →

FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

Kodiac sells research compounds for investigative use only.

Pinoline

Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

Quick actions

Categories

Help and policies

Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

Adjacent monographs