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Bruce K. Cassels

16 papers in the library · 197 citations · publishing 1994-2026

Papers

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N -Benzyl-Tryptamine Derivatives as Serotonin 5-HT 2 Receptor Ligands: Synthesis and Structure-Affinity/Activity Relationships

ACS Omega May 13, 2026 Darío Martínez-afani, Breno A. Soares, Jaime Mella-Raipán et al. 1 citation

High Resolution Image Download MS PowerPoint Slide Serotonin 5-HT 2 receptor ligands have attracted the attention of medicinal chemists for the last half-century, first as hallucinogens and later for their antipsychotic, appetite suppressant, antiaddictive and antidepressant potential. Unlike the very potent N -benzylphenethylamine derivatives that include the abundantly studied NBOMe drugs, N...

DOI: 10.1021/acsomega.5c13162 (opens in new tab) Serotonin Agonist 5-HT Receptor Action physics +3

Alkaloids of the Cactaceae — The Classics

Natural Product Communications April 20, 2026 Bruce K. Cassels 11 citations

Alkaloids of the Cactaceae have been studied for the last 120 years. The first half of that period provided the “classic” compounds, after which a large number of usually very similar analogs were isolated or determined with modern methods. Although some unusual synthetic approaches have been developed, their preparation is generally quite straightforward. Their biosynthesis has been studied...

N-Benzyl-tryptamine Derivatives as Serotonin 5-HT2A Receptor (5-HT2AR) Agonists: Focus on Different In Vitro 5-HT2AR Activity Profiles.

ACS Chemical Neuroscience March 20, 2026 Eline Pottie, Emma Vertriest, Darío Martínez-afani et al.

N-Benzyl-derived phenethylamines are highly active (psychedelic) 5-HT2AR (serotonin 2A receptor) agonists used as biochemical tools and on the drug market. The impact of adding an N-benzyl substituent to the tryptamine core structure has scarcely been studied. A recent systematic exploration of N-benzyl-substituted (5-MeO-)tryptamines revealed a surprisingly low activity in a Ca2+ mobilization...

The entactogen MDMA (3,4-methylenedioxymethamphetamine, "Ecstasy") disrupts helping behaviour while reinforcing electrophysiological indicators of potentially associated synaptic plasticity in male Sprague-Dawley rats.

Frontiers in Pharmacology 2026 Patricio Sáez-briones, Amanda Silva-Rodríguez, Michelle Morales-Vidal et al.

In humans, empathy is expressed through various prosocial behaviours between individuals that may be enhanced after intake of the synthetic entactogen MDMA (3,4-methylenedioxymethamphetamine, "Ecstasy") as the behavioural expression of the so-called entactogenic syndrome. Rodents may also exhibit empathy-like behaviours, such as social interaction and helping behaviour. In this regard, while...

DOI: 10.3389/fphar.2026.1779772 (opens in new tab) Full text (opens in new tab) Serotonin 3,4-methylenedioxymethamphetamine Helping behaviour Oxytocin

Effect of Bulky N-Dibenzofuranylmethyl Substitution on the 5-HT2 Receptor Affinity and Efficacy of a Psychedelic Phenethylamine.

ACS Chemical Neuroscience February 7, 2024 Breno A. Soares, Thirumal Yempala, Darío Martínez-afani et al. 4 citations

The introduction of arylmethyl substituents on the amine nitrogen atom of phenethylamines and tryptamines often results in profound increases in their affinity and functional activity at 5-HT2 serotonin receptors. To probe the sensitivity of this effect to substantially larger N-substituents, ten derivatives of the well-characterized psychedelic phenethylamine 2C-B were prepared by appending...

DOI: 10.1021/acschemneuro.3c00639 (opens in new tab) Full text (opens in new tab) 5-ht2 receptor agonism 5-ht2 receptor binding Bulky n-substituents Docking poses +6

Aromatic Bromination Abolishes the Psychomotor Features and Pro-social Responses of MDMA ("Ecstasy") in Rats and Preserves Affinity for the Serotonin Transporter (SERT).

Frontiers in Pharmacology February 28, 2019 Patricio Sáez-briones, Vicente Castro-Castillo, Gabriela Díaz-véliz et al. 4 citations

The entactogen MDMA (3,4-methylenedioxy-methamphetamine, “Ecstasy”) exerts its psychotropic effects acting primarily as a substrate of the serotonin transporter (SERT) to induce a non-exocytotic release of serotonin. Nevertheless, the roles of specific positions of the aromatic ring of MDMA associated with the modulation of typical entactogenic effects, using analogs derived from the MDMA...

5-HT2 receptor binding, functional activity and selectivity in N-benzyltryptamines

PLoS One January 10, 2019 Miguel A Toro-Sazo, José Brea, María I. Loza et al.

The last fifteen years have seen the emergence and overflow into the drug scene of "superpotent" N-benzylated phenethylamines belonging to the "NBOMe" series, accompanied by numerous research articles. Although N-benzyl substitution of 5-methoxytryptamine is known to increase its affinity and potency at 5-HT2 receptors associated with psychedelic activity, N-benzylated tryptamines have been...

Dark Classics in Chemical Neuroscience: Mescaline

ACS Chemical Neuroscience May 30, 2018 Bruce K. Cassels, Patricio Sáez-briones 84 citations

Archeological studies in the United States, Mexico, and Peru suggest that mescaline, as a cactus constituent, has been used for more than 6000 years. Although it is a widespread cactus alkaloid, it is present in high concentrations in few species, notably the North American peyote ( Lophophora williamsii) and the South American wachuma ( Trichocereus pachanoi, T. peruvianus, and T. bridgesii)....

SYNTHESIS OF N-(HALOGENATED) BENZYL ANALOGS OF SUPERPOTENT SEROTONIN LIGANDS

Journal of the Chilean Chemical Society September 1, 2014 Cristián Tirapegui, Miguel A Toro-Sazo, Bruce K. Cassels 1 citation

In the last four years a group of extremely potent designer drugs, the N-benzylated phenylethylamines known as the NBOMe series, has surfaced on the street and in the news media. Although data documenting their high affinity and preference for 5-HT2 serotonin receptors abound (5-HT2A receptor activation is generally associated with the action of the "classical" hallucinogens), relatively little...

Behavioral profiles in rats distinguish among "ecstasy," methamphetamine and 2,5-dimethoxy-4-iodoamphetamine: Mixed effects for "ecstasy" analogues.

Behavioral Neuroscience October 1, 2010 David Quinteros-Muñoz, Patricio Sáez-briones, Gabriela Díaz-véliz et al. 12 citations

3,4-methylenedioxymethamphetamine (MDMA; "ecstasy") is a psychoactive drug structurally related to other phenylisopropylamines acting as stimulants or hallucinogens in humans. Although MDMA has a pharmacological identity of its own, the distinction of its acute effects from those of stimulants or even hallucinogens is controversial. In this work, dose-response curves (0.25, 0.5, 1, 3, 5, and 10...

Functional selectivity of hallucinogenic phenethylamine and phenylisopropylamine derivatives at human 5-hydroxytryptamine (5-HT)2A and 5-HT2C receptors.

Journal of Pharmacology and Experimental Therapeutics June 2007 Pablo R Moya, Kelly A Berg, Manuel A Gutiérrez-Hernandez et al.

2,5-Dimethoxy-4-substituted phenylisopropylamines and phenethylamines are 5-hydroxytryptamine (serotonin) (5-HT)(2A/2C) agonists. The former are partial to full agonists, whereas the latter are partial to weak agonists. However, most data come from studies analyzing phospholipase C (PLC)-mediated responses, although additional effectors [e.g., phospholipase A(2) (PLA(2))] are associated with...

4-Bromo-2,5-dimethoxyphenethylamine (2C-B) and structurally related phenylethylamines are potent 5-HT2A receptor antagonists in Xenopus laevis oocytes.

British Journal of Pharmacology April 1, 2004 Claudio A Villalobos, Paulina Bull, Patricio Sáez et al. 50 citations

1. We recently described that several 2-(2,5-dimethoxy-4-substituted phenyl)ethylamines (PEAs), including 4-I=2C-I, 4-Br=2C-B, and 4-CH(3)=2C-D analogs, are partial agonists at 5-HT(2C) receptors, and show low or even negligible intrinsic efficacy at 5-HT(2A) receptors. These results raised the proposal that these drugs may act as 5-HT(2) antagonists. 2. To test this hypothesis, Xenopus laevis...

DOI: 10.1038/sj.bjp.0705722 (opens in new tab) Full text (opens in new tab) 5-ht2a receptor Psychoactive compounds Psychoactive effects Phenylethylamines +5

Differences in potency and efficacy of a series of phenylisopropylamine/phenylethylamine pairs at 5-HT(2A) and 5-HT(2C) receptors.

British Journal of Pharmacology June 1, 2002 Claudio Acuña-Castillo, Claudio A Villalobos, Pablo R Moya et al.

The pharmacological profile of a series of (+/-)-2,5-dimethoxy-4-(X)-phenylisopropylamines (X=I, Br, NO(2), CH(3), or H) and corresponding phenylethylamines, was determined in Xenopus laevis oocytes injected with cRNA coding for rat 5-HT(2A) or 5-HT(2C) receptors. The efficacy and relative potency of these drugs were determined and compared to classical 5-HT(2) receptor agonists and...

ALEPH-2, a suspected anxiolytic and putative hallucinogenic phenylisopropylamine derivative, is a 5-HT2a and 5-HT2c receptor agonist.

Life Sciences November 17, 2000 Claudio Acuña-Castillo, C Scorza, Miguel Reyes-Parada et al. 3 citations

To assess the pharmacodynamic profile of ALEPH-2, a phenylisopropylamine derivative with alleged anxiolytic and hallucinogenic properties, Xenopus laevis oocytes were microinjected with either of the rat cRNA for the 5-HT2A or the 5-HT2C receptor. Concentration-response curves were obtained following the exposure of the oocytes to varying concentrations of either ALEPH-2 or 5-hydroxytryptamine...

(+/-)-1-(2,5-Dimethoxy-4-ethylthiophenyl)-2-aminopropane (ALEPH-2), a novel putative anxiolytic agent lacking affinity for benzodiazepine sites and serotonin-1A receptors.

Naunyn-Schmiedeberg's Archives of Pharmacology November 1, 1996 Miguel Reyes-Parada, C Scorza, V Romero et al. 6 citations

Serotonergic behavioral responses, effects on motor activity and core temperature, and binding properties of the novel putative anxiolytic amphetamine derivative (+/-)1-(2,5-dimethoxy-4-ethylthio-phenyl)-2-aminopropane (ALEPH-2), were examined in rodents in order to elucidate the mechanism underlying its anxiolytic-like effect. After peripheral administration in rats, ALEPH-2 induced some...

Alpha-adrenergic and 5-HT2-serotonergic effects of some beta-phenylethylamines on isolated rat thoracic aorta.

General pharmacology 1994 Patricio Sáez, Y Borges, E Gonzalez et al. 21 citations

1. 2C-H [2-(2,5-dimethoxyphenyl)ethylamine] (pD2 = 6.74), TMPEA [2,(2,4,5-trimethoxyphenyl)ethylamine] (pD2 = 5.83), 2C-D [2-(2,5-dimethoxy-4-methylphenyl)ethylamine] (pD2 = 5.06), homoveratrylamine [DMPEA, 2-(4,5-dimethoxyphenyl)ethylamine] (pD2 = 4.46) and homopiperonylamine [MDPEA, 2-(3,4-methylenedioxyphenyl)ethylamine] (pD2 = 4.19), elicit concentration-dependent contraction of the...