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A. Halberstadt

3 papers in the library · 131 citations · publishing 2016-2020

Papers

Return of the lysergamides. Part II: Analytical and behavioural characterization of N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ)

Drug Testing and Analysis June 6, 2016 S. Brandt, P. Kavanagh, F. Westphal et al. 62 citations

Two new psychoactive substances, AL-LAD and LSZ, which are analogs of LSD, were analytically characterized using multiple techniques including NMR, mass spectrometry, and infrared analysis. In male mice, both compounds produced LSD-like behavioral responses in a head-twitch assay, with dose-dependent effects peaking at 200 µg/kg. LSZ was equipotent to LSD (ED50 = 114.2 nmol/kg vs. 132.8 nmol/kg), while AL-LAD was slightly less potent (ED50 = 174.9 nmol/kg). The direct translation of these potency comparisons to humans requires further study. Providing chemical and pharmacological data on emerging substances aids research communities focused on substance use and forensic identification.

Return of the lysergamides. Part III: Analytical characterization of N6-ethyl-6-norlysergic acid diethylamide (ETH-LAD) and 1-propionyl ETH-LAD (1P–ETH-LAD)

Drug Testing and Analysis May 10, 2017 S. Brandt, P. Kavanagh, F. Westphal et al. 44 citations

Two new lysergamides, ETH-LAD and 1P-ETH-LAD, were characterized using multiple analytical techniques including GC-MS, mass spectrometry, infrared analysis, HPLC, and NMR. 1P-ETH-LAD had not previously been described in scientific literature. When incubated with human serum at 37°C, 1P-ETH-LAD converted to ETH-LAD over time, suggesting it may act as a pro-drug. 1P-ETH-LAD remained detectable in serum after 24 hours. This work provides analytical data for clinicians and toxicologists who may encounter these substances on the new psychoactive substances market.

The selective 5-HT2A receptor agonist 25CN-NBOH: structure-activity relationship, in vivo pharmacology, and in vitro and ex vivo binding characteristics of [3H]25CN-NBOH.

Biochemical Pharmacology April 13, 2020 A. Jensen, A. Halberstadt, Emil Märcher-Rørsted et al. 25 citations

Modifications to specific positions on the 25CN-NBOH molecule, a highly selective 5-HT2A receptor agonist, can retain or reduce its activity. Six new analogs were tested; 3′-methyl and fused-ring variants kept high 5-HT2A receptor activity, while 3′-methoxy and 3′-ethyl versions lost binding and potency. All six analogs showed only partial agonism or antagonism. In mice, 25CN-NBOH and a close analog triggered head-twitch responses (a hallmark of 5-HT2A activation) and reduced marble-burying behavior, suggesting potential benefits for cognitive rigidity disorders. A tritium-labeled version of 25CN-NBOH showed high binding affinity and selectivity for 5-HT2A receptors in rat brain tissue, providing a new tool for future receptor studies.