Classical psychedelic drugs such as the tryptamine psilocybin can alter temporal perception. Previously, the phenylethylamine psychedelic 2,5-dimethoxy-4-iodoamphetamine (DOI), a 5-HT2A receptor agonist, altered timing precision and accuracy in mice performing the discrete-trials temporal discrimination task (TDT), a retrospective timing task where subjects differentially respond depending on...
Phantom limb pain (PLP) is a refractory condition defined by pain experienced in a missing limb. Psilocybin, a classical serotonergic psychedelic drug, can alleviate various treatment-resistant disorders but has scantly been investigated for chronic pain. This placebo-controlled, double-blind, randomized clinical pilot trial (NCT05224336) tested the feasibility, tolerability, and preliminary...
NeuropsychopharmacologyJuly 21, 2026Alannah Miranda, Breanna M Holloway, Elizabeth Peek et al.
Cannabis use is highly prevalent among people with bipolar disorder, potentially due to a desire to self-medicate against symptoms, such as racing thoughts and poor concentration. Such symptoms are associated with attention and inhibitory control deficits, functions that are regulated in-part by temporal perception. Temporal perception is impaired in BD and is slowed by acute cannabis exposure....
Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed for mood and anxiety disorders, the same conditions under which psychedelic-assisted therapies are gaining renewed interest. However, it remains unclear how SSRI treatment may influence sensitivity to psychedelics, particularly through the shared engagement of serotonergic pathways. Here, we used the head-twitch response...
Correction 1: Table 1.The analyses were conducted using the correct data, and all results, interpretations, and conclusions in the paper remain fully accurate.The issue is limited to the presentation of values in the table.Correction 2: p 4733, second paragraph, 1 st sentence.Thigmotaxis was evaluated to assess potential anxiety-like effects induced by the compounds.When comparing the tested...
A light-induced cyclization via a radical spin-center shift process that results in the direct functionalization of the indole ring at the C4-position is developed into a practical method for the synthesis of medicinally active, ring-constrained tryptamine analogs. Amino acids were coupled to tryptamine and irradiated with UV light to produce a library of lactams bridging the C3- and...
3,4-Methylenedioxymethamphetamine (MDMA), commonly known as ecstasy, shows promise in treating depression and post-traumatic stress disorder (PTSD), resulting in breakthrough status. However, concerns regarding MDMA's abuse potential and cytotoxicity have sparked interest in developing safer analogues with similar therapeutic benefits. This study investigated the pharmacological properties of...
With a resurgence in interest in psychedelics as rapid-acting and durable neuroplastic therapies, there is a critical need to develop more selective 5-HT 2A agonists to investigate the basic neurobiological mechanisms of psychedelics. Here, we show that selectivity for 5-HT 2A over the closely related 5-HT 2C receptor can be leveraged using structure-based design to target residue L123 2.53 in...
Treating amotivated states remains difficult. Classical psychedelic drugs (5-HT2A receptor agonists) such as LSD and psilocybin have shown therapeutic potential in treating such symptoms, but their development has been hindered by their undesirable hallucinogenic effects. There is increasing evidence that administration of psychedelics at dose levels too low to evoke a hallucinogenic effect...
Abstract Background and Hypothesis Visual hallucinations (VH) are a core symptom of both Lewy body diseases (LBDs; eg, Parkinson’s disease and dementia with Lewy bodies) and serotonergic psychedelics (SPs; eg, psilocybin and mescaline). While these conditions differ in etiology, overlapping phenomenology, and neural mechanisms suggest shared pathways. This review explores similarities and...
The development of lysergic acid diethylamide (LSD) derivatives and analogs continues to inform the design of novel receptor probes and potentially new medicines. On the other hand, a number of newly developed LSD derivatives have also emerged as recreational drugs, leading to reports of their detection in some countries. One position in the ergoline scaffold of LSD that is frequently targeted...
1-Acetyl-N,N-diethyllysergamide (1A-LSD, ALD-52) was first synthesized in the 1950s and found to produce psychedelic effects similar to those of LSD. Evidence suggests that ALD-52 serves as a prodrug in vivo and hydrolysis to LSD is likely responsible for its activity. Extension of the N1-alkylcarbonyl chain gives rise to novel lysergamides, which spurred further investigations into their...
The classical psychedelic drug (+)-lysergic acid diethylamide (LSD) continues to attract considerable multidisciplinary interest, and over the last eight decades, many derivatives and analogs of LSD have been synthesized. One site on the ergoline scaffold of LSD that has been frequently modified is the N1-position, with the N1-acylated LSD derivative 1-acetyl-LSD (1A-LSD, ALD-52) being one of...
Preclinical investigations have shown that N-ethyl-N-isopropyllysergamide (EIPLA) exhibits lysergic acid diethylamide (LSD)-like properties, which suggests that it might show psychoactive effects in humans. EIPLA is also an isomer of N6 -ethylnorlysergic acid N,N-diethylamide (ETH-LAD), a lysergamide known to produce psychedelic effects in humans that emerged as a research chemical. EIPLA was...
Functional selectivity in the context of serotonin 2A (5-HT 2A ) receptor agonists is often described as differences psychedelic compounds have in the activation of Gq vs β-arrestin signaling in the brain and how that may relate to inducing psychoactive and hallucinatory properties with respect to each other. However, the presence of 5-HT 2A receptors throughout the body in several cell types,...
Abstract Serotonergic psychedelics possess considerable therapeutic potential. Although 5-HT 2A receptor activation mediates psychedelic effects, prototypical psychedelics activate both 5-HT 2A -Gq/11 and β-arrestin2 transducers, making their respective roles unclear. To elucidate this, we develop a series of 5-HT 2A -selective ligands with varying Gq efficacies, including β-arrestin-biased...
Summary Serotonergic psychedelics possess considerable therapeutic potential. Although 5-HT 2A receptor activation mediates psychedelic effects, prototypical psychedelics activate both 5-HT 2A -Gq/11 and β-arrestin2 signaling, making their respective roles unclear. To elucidate this, we developed a series of 5-HT 2A -selective ligands with varying Gq efficacies, including β-arrestin-biased...
Hallucinations limit widespread therapeutic use of psychedelics as rapidly acting antidepressants. Here we profiled the non-hallucinogenic lysergic acid diethylamide (LSD) analog 2-bromo-LSD (2-Br-LSD) at more than 33 aminergic G protein-coupled receptors (GPCRs). 2-Br-LSD shows partial agonism at several aminergic GPCRs, including 5-HT2A, and does not induce the head-twitch response (HTR) in...
Abstract Rationale 4-Thio-substituted phenylalkylamines such as 2,5-dimethoxy-4-ethylthiophenethylamine (2C-T-2) and 2,5-dimethoxy-4- n -propylthiophenethylamine (2C-T-7) produce psychedelic effects in humans and have been distributed as recreational drugs. Objectives The present studies were conducted to examine the structure–activity relationships (SAR) of a series of 4-thio-substituted...
Abstract Lysergic acid diethylamide (LSD) is known to induce powerful psychoactive effects in humans, which cemented its status as an important tool for clinical research. A range of analogues and derivatives has been investigated over the years, including those classified as new psychoactive substances. This study presents the characterization of the novel lysergamide N , N...
Derivatives of (2-aminopropyl)indole (API) and (2-aminopropyl)benzofuran (APB) are new psychoactive substances which produce stimulant effects in vivo. (2-Aminopropyl)benzo[β]thiophene (APBT) is a novel sulfur-based analog of API and APB that has not been pharmacologically characterized. In the current study, we assessed the pharmacological effects of six APBT positional isomers in vitro, and...
Abstract The psychopharmacological properties of the psychedelic drug lysergic acid diethylamide (LSD) have attracted the interest of several generations of scientists. While further explorations involving novel LSD‐type compounds are needed to assess their potential as medicinal drugs, the emergence of novel derivatives as recreational drugs has also been observed. 1‐Valeroyl‐LSD (also known...
HIV-associated neurocognitive disorder (HAND) is commonly observed in persons living with HIV (PWH) and is characterized by cognitive deficits implicating disruptions of fronto-striatal neurocircuitry. Such circuitry is also susceptible to alteration by cannabis and other drugs of abuse. PWH use cannabis at much higher rates than the general population, thus prioritizing the characterization of...
A novel analogue of psilocybin was produced by hybrid chemoenzymatic synthesis in sufficient quantity to enable bioassay. Utilizing purified 4-hydroxytryptamine kinase from Psilocybe cubensis, chemically synthesized 5-methylpsilocin (2) was enzymatically phosphorylated to provide 5-methylpsilocybin (1). The zwitterionic product was isolated from the enzymatic step with high purity utilizing a...
The 5-HT2A receptor is thought to be the primary target for psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) and other serotonergic hallucinogens (psychedelic drugs). Although a large amount of experimental work has been conducted to characterize the pharmacology of psilocybin and its dephosphorylated metabolite psilocin (4-hydroxy-N,N-dimethyltryptamine), there has been little systematic...