ACS Pharmacology & Translational Science
November 2, 2022
Eline Pottie, Marilyn Naeem, Vamshikrishna Reddy Sammeta et al.
91 citations
Psilocybin is a prodrug for psilocin, which produces psychedelic effects by activating serotonin 5-HT2A receptors. This study examined three naturally occurring compounds from psilocybin-containing mushrooms—psilocybin, baeocystin, and aeruginascin—along with their synthetic 4-acetoxy and 4-hydroxy analogues. In cell-based assays, secondary and tertiary tryptamines with 4-acetoxy or 4-hydroxy substitutions showed nanomolar affinity for several human serotonin receptor subtypes, including 5-HT2A and 5-HT1A. In mice, only the tertiary amines psilocin, psilocybin, and psilacetin induced head twitch responses (ED50 0.11–0.29 mg/kg), indicating psychedelic-like activity, which was blocked by a 5-HT2A antagonist.
Journal of Natural Products
February 20, 2020
Alexander M. Sherwood, Adam L. Halberstadt, Adam K. Klein et al.
79 citations
A new synthetic method allows access to tryptamine natural products found in psilocybin-producing mushrooms. Laboratory and animal experiments tested whether these compounds are psychoactive. In mice, the natural product baeocystin did not produce a head twitch response, a behavioral marker of psychedelic activity, even though its predicted breakdown product, norpsilocin, strongly activates the 5-HT2A receptor, which is associated with psychedelic effects. This suggests that baeocystin itself may not be psychedelic, despite its metabolite's activity.
Chemistry - A European Journal
February 26, 2020
Janis Fricke, Robert B. Kargbo, Lars Regestein et al.
48 citations
Psilocybin, the main psychoactive alkaloid in Psilocybe mushrooms, is being tested as a treatment for depression. Pharmaceutical psilocybin is currently made by synthetic chemistry. Replacing a difficult chemical phosphorylation step with the mushroom enzyme PsiK allowed production of one gram of psilocybin from psilocin in 20 minutes. A pilot-scale protocol also yielded 150 mg of active, soluble PsiK enzyme. This combination of tryptamine chemistry and enzymatic catalysis may provide access to psilocybin at potentially lower cost.
ACS Omega
July 1, 2020
Jessica Sable, Tura Patterson, Gary Tarpley et al.
41 citations
A new chemical process produces over one kilogram of high-purity psilocybin, the active compound in psychedelic mushrooms, using a second-generation synthesis designed for large-scale manufacturing. The method improves on earlier procedures by optimizing the Speeter-Anthony tryptamine synthesis to create the intermediate psilocin with better control and impurity removal. It then directly phosphorylates psilocin with phosphorous oxychloride, avoiding a complex benzyl-protecting group strategy used in previous methods. This approach addresses challenges in yield, purity, atom economy, and suitability for pilot plant-scale reactors, providing a more efficient and consistent route for producing psilocybin under current Good Manufacturing Practices.
ChemPlusChem
October 1, 2020
Claudius Lenz, Alexander M. Sherwood, Robert B. Kargbo et al.
40 citations
Psilocybe fungi, known as magic mushrooms, produce psilocybin from the amino acid L-tryptophan. Recent research shows these fungi have a more varied secondary metabolism derived from this amino acid. This review describes psilocybin and related compounds, including blue-colored psilocyl oligomers, beta-carbolines, and N,N-dimethyl-L-tryptophan, along with current knowledge of their biosynthesis. The work covers pharmacological, medicinal, ecological, biochemical, and evolutionary aspects of these natural products.
ACS Omega
December 2, 2020
Alexander M. Sherwood, Romain Claveau, Rafael Lancelotta et al.
38 citations
A multigram-scale process was developed to produce 5-MeO-DMT, a psychedelic natural product from the toad Incilius alvarius, for clinical use. An optimized Fischer indole reaction yielded 5-MeO-DMT freebase, which was converted to the 1:1 succinate salt, producing 136 g of crystalline active pharmaceutical ingredient with 99.86% purity by HPLC and a net yield of 49%. The report details in-process monitoring, validated analytical methods, impurity formation and removal, and solid-state characterization essential for clinical development.
ChemBioChem
May 31, 2019
Janis Fricke, Alexander M. Sherwood, Robert B. Kargbo et al.
38 citations
Psilocybin and its precursor baeocystin are indole alkaloids from psychotropic Psilocybe mushrooms, currently under clinical investigation for depression and anxiety. A biocatalytic route was developed to synthesize 6-methylated psilocybin and baeocystin from 4-hydroxy-6-methyl-L-tryptophan, using the Psilocybe cubensis enzymes PsiD and PsiK for decarboxylation and phosphorylation, and PsiM for N-methylation. An in silico structural model of PsiM revealed a well-conserved SAM-binding core with peripheral nonconserved elements that likely determine substrate preferences.
Synthesis
January 8, 2020
Robert B. Kargbo, Alexander M. Sherwood, Poncho Meisenheimer et al.
31 citations
An improved chemical synthesis of psilocybin produces multigram quantities in five steps with 23% overall yield from an inexpensive acetoxyindole starting material. The protocol identifies critical in-process parameters and isolates psilocybin without chromatography, thin-layer chromatography, or aqueous workup. The procedure emphasizes process control and impurity fate and removal to deliver high-quality psilocybin.
ChemBioChem
April 28, 2022
Claudius Lenz, Sebastian Dörner, Felix Trottmann et al.
26 citations
Psilocybin, the main alkaloid in psychedelic mushrooms, acts as a prodrug to psilocin, a potent psychedelic that alters human consciousness. Its positional isomer bufotenin differs in reported pharmacology. Experiments tested whether psilocin's C-4 hydroxy group influences properties through pseudo-ring formation via an intramolecular hydrogen bond (IMHB). NMR spectroscopy and quantum chemical calculations compared hydrogen bond behavior in 4- and 5-hydroxylated tryptamines. Evidence shows a pseudo-ring in psilocin and that sidechain/hydroxyl interactions affect oxidation kinetics. The propensity to form IMHBs leads to more uncharged species that cross the blood-brain barrier, unlike bufotenin. This helps explain psilocin's pharmacology and supports developing psilocybin as a therapy for major depressive disorder.
Nature Communications
February 12, 2025
Farid Aboharb, Pasha A. Davoudian, Ling-Xiao Shao et al.
19 citations
A machine-learning pipeline using light sheet fluorescence microscopy to measure immediate early gene expression in mouse brain tissues classified psychoactive drugs with 67% accuracy across eight conditions, significantly above the 12.5% chance level. Psilocybin was discriminated from 5-MeO-DMT, ketamine, MDMA, or acute fluoxetine with over 95% accuracy. Shapley additive explanation identified brain regions driving predictions, suggesting a novel approach for characterizing and validating psychoactive drugs with psychedelic properties.
ACS Chemical Neuroscience
January 8, 2024
Alexander M. Sherwood, Elise K. Burkhartzmeyer, Samuel E. Williamson et al.
18 citations
Psilocin, a metabolite of psilocybin, produces psychedelic effects in vivo, while norpsilocin, which differs by a single N-methyl group, does not. To explore this, eight norpsilocin derivatives with varied secondary amine groups were synthesized to increase lipophilicity and brain permeability. In mouse head-twitch response (HTR) studies, extending norpsilocin's N-methyl group to an N-ethyl group (4-HO-NET) produced psilocin-like activity (ED50 = 1.4 mg/kg). N-allyl, N-propyl, N-isopropyl, and N-benzyl derivatives also induced HTRs (ED50 = 1.1–3.2 mg/kg), with variable maximum effects (26–77 total HTR events). Bulky tert-butyl or cyclohexyl groups did not elicit psilocin-like HTRs. In vitro, these tryptamines interacted with multiple serotonin receptor subtypes and other CNS proteins.
Journal of Natural Products
March 5, 2021
Janis Fricke, Alexander M. Sherwood, Adam L. Halberstadt et al.
18 citations
A novel analogue of psilocybin, 5-methylpsilocybin, was produced through a hybrid chemoenzymatic synthesis, combining chemical synthesis of 5-methylpsilocin with enzymatic phosphorylation using a purified kinase from Psilocybe cubensis. The product was isolated with high purity via solvent-antisolvent precipitation. In a mouse head-twitch response assay, 5-methylpsilocybin showed psychedelic-like activity more potent than dimethyltryptamine but less potent than psilocybin.
Acta Crystallographica Section C Structural Chemistry
December 20, 2021
Alexander M. Sherwood, Robert B. Kargbo, Kristi W. Kaylo et al.
10 citations
Psilocybin, a natural product from psychoactive fungi, exists in three distinct crystal forms: Hydrate A, Polymorph A, and Polymorph B. This article presents newly solved crystal structures for the two anhydrate forms using X-ray diffraction and computational methods. Analysis of psilocybin samples produced between 1963 and 2021 shows that all contain one or more of these three forms, with no additional forms needed to explain their diffraction patterns. The composition correlates with process methods, sample age, and storage conditions. The authors also identify that a recently granted patent incorrectly described a mixture of about 81% Polymorph A and 19% Polymorph B as a single-phase variant, recommending revision of such characterizations.
bioRxiv (Cold Spring Harbor Laboratory)
November 3, 2022
Sarah J. Jefferson, Ian Gregg, Mark Dibbs et al.
5 citations
preprint
The short-acting psychedelic 5-MeO-DMT increases head-twitch response in mice in a dose-dependent manner, with a shorter duration than psilocybin. It strongly suppresses social ultrasonic vocalizations during mating behavior and produces long-lasting increases in dendritic spine density in the medial frontal cortex by elevating the rate of spine formation, but unlike psilocybin, it does not affect spine size. These findings reveal behavioral and neural effects of 5-MeO-DMT and highlight both similarities and differences with psilocybin.
Acta Crystallographica Section E Crystallographic Communications
May 6, 2022
Marilyn Naeem, Alexander M. Sherwood, A.r. Chadeayne et al.
5 citations
The crystal structure of baeocystin, a naturally occurring alkaloid related to psilocybin, was determined. The molecule exists as a zwitterion with an intramolecular hydrogen bond between its ammonium and phosphate groups. In the crystal, these molecules form a three-dimensional network through N—H...O and O—H...O hydrogen bonds.
ACS Omega
February 7, 2022
Robert B. Kargbo, Alexander M. Sherwood, Poncho Meisenheimer et al.
5 citations
A thermodynamically controlled crystallization process for psilocybin, a serotonergic agonist granted breakthrough therapy status for depression, produces crystals with stronger interactions, a controlled particle size distribution, and an improved impurity profile compared to a faster, kinetically controlled process that yields smaller particles. Real-time monitoring with high-resolution inline microscopy measured particle size and metastable zone width and nucleation induction. Water recrystallization forms polymorph B (trihydrate) independently of the method, while polymorph A (anhydrate) and polymorph H (anhydrate) depend on drying: room-temperature vacuum drying yields mainly polymorph A, and heating even at low temperatures produces a mixture of polymorphs A and H.
Chemistry - A European Journal
April 9, 2025
Tim Schäfer, Thomas Krüger, Jakob Worbs et al.
2 citations
A reusable solid-phase resin coated with five enzymes—three from Psilocybe mushrooms and two from E. coli—converts 4-hydroxy-L-tryptophan into psilocybin quantitatively in a proof-of-principle in vitro experiment. This biocatalytic approach offers a sustainable, selective alternative to synthetic production for the drug candidate being tested in advanced clinical trials for major depressive disorder.
Journal of Labelled Compounds and Radiopharmaceuticals
July 1, 2025
Rodney D. Brown, Niall M. Hamilton, Connor Mallon et al.
1 citation
Three new radiolabelled versions of the psychedelic compounds psilocin, psilocybin, and 5-MeO-DMT were synthesized, each with carbon-14 at the 2-position of the indole ring. The synthesis used a common route: attaching the dimethylaminoethyl side chain to substituted indole intermediates via oxalyl chloride, dimethylamine, and lithium aluminium hydride reduction. Psilocybin-2-14C at 234 μCi/mg showed limited stability, but a 5.5-fold dilution with unlabelled psilocybin maintained >97.5% radiochemical purity after one month at ≤−70°C. 5-MeO-DMT-2-14C succinate at 173 μCi/mg remained 98.0% pure after six months at ≤−70°C, supporting long-term studies. These labelled compounds enable in vivo pharmacokinetic and metabolic studies of psychedelic tryptamines, aiding ADME and mass balance research for potential regulatory approval in treating depression, anxiety, and PTSD.
ChemRxiv
June 2, 2023
Samuel E. Williamson, Alexander M. Sherwood
1 citation
The Church of Psilomethoxin claims its sacrament is a novel tryptamine, psilomethoxin, produced by adding 5-MeO-DMT to the substrate of cultivated Psilocybe mushrooms. Using ultra-performance liquid chromatography with high-resolution mass spectrometry (UPLC-HRMS) and authentic reference standards, this analysis found no evidence of psilomethoxin in samples of the material sold to members online. Instead, the samples unambiguously contained psilocybin, baeocystin, and psilocin. The findings indicate that the church's claims about biosynthesis of psilomethoxin are likely misguided, with implications for public health and safety.
ACS Chemical Neuroscience
March 3, 2026
Samuel E. Williamson, Elise K. Burkhartzmeyer, Michael T. Faley et al.
To support ongoing clinical trials, the major human metabolites of psilocybin—psilocin-O-glucuronide and 4-hydroxyindole-3-acetic acid (4-HIAA)—along with putative minor metabolites and several deuterium-labeled derivatives, were synthesized on a preparative scale. When assayed for engagement at seven serotonin receptor subtypes using a BRET-based binding assay, only psilocin exhibited any discernible binding. Given the high cost and challenging preparation of these compounds, the work provides a comprehensive guide for researchers to access these resources, advancing both basic and clinical research with psilocybin and its metabolites.