ArticlePsychopharmacology2023
Alkoxy chain length governs the potency of 2-benzylbenzimidazole 'nitazene' opioids associated with human overdose.
Article in Psychopharmacology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers.
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Who cites it
28 citing papers in PubMed, 39 citations in OpenAlex.
- Dual-target mu opioid-dopamine DEuropean journal of medicinal chemistry · 2026Article
- Preclinical pharmacology of N-pyrrolidino "nitazene" opioids appearing in nonmedical drug markets.The Journal of pharmacology and experimental therapeutics · 2026Article
- Landscaping the Nitazene Scaffold to Identify Novel Mu-Opioid Receptor Modulators: From Molecular Design and Chemical Synthesis to Pharmacological Profiling.Journal of medicinal chemistry · 2026Article
- Novel 2-Benzylbenzimidazole Opioids: Emerging Drugs of Abuse and Pharmacological Considerations with Nitazene Analogs.Current pain and headache reports · 2026Review
- Identification and Characterization of the Designer Opioid N-Pyrrolidino Fluetonitazene in Nasal Spray.Drug testing and analysis · 2026Article
- Fatal intoxications with nitazenes: postmortem findings, toxicology, and in vitro characterization at the μ-opioid receptor of six nitazene analogues.Archives of toxicology · 2026Article
- Slow Dissociation of Nitazenes from thebioRxiv : the preprint server for biology · 2026Article
- Article
- The nitazene epidemic in Estonia: a first report.European journal of public health · 2025Article
- Post-Mortem Identification and Toxicological Findings of Fluetonitazepyne and Isotonitazepyne.Drug testing and analysis · 2025Article
- Article
- Identification of the Novel Synthetic Opioid N-Pyrrolidino Isotonitazene at an Australian Drug Checking Service.Drug testing and analysis · 2025Article
- Nonpharmacological and pharmacological influences on opioid effects: A review of clinical research findings.The Journal of pharmacology and experimental therapeutics · 2025Review
- The emergence of nitazenes: a new chapter in the synthetic opioid crisis.Archives of toxicology · 2025Review
- Nitazenes: The Emergence of a Potent Synthetic Opioid Threat.Molecules (Basel, Switzerland) · 2025Review
- Pharmacology of newly identified nitazene variants reveals structural determinants of affinity, potency, selectivity for mu opioid receptors.Neuropharmacology · 2025Article
- A Comprehensive Narrative Review of Protonitazene: Pharmacological Characteristics, Detection Techniques, and Toxicology.Basic & clinical pharmacology & toxicology · 2025Review
- A putative binding model of nitazene derivatives at the μ-opioid receptor.Neuropharmacology · 2025Article
- Latest developments in small molecule analgesics: heterocyclic scaffolds I.Future medicinal chemistry · 2025Review
- Comparison of the Metabolic Profiles Associated with Protonitazene and Protonitazepyne in Two Severe Poisonings.Metabolites · 2025Article
Corrections and comments
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Authors and funding
8 authors at 2 institutions in 2 countries.
Funding
Abstract
rationaleNovel synthetic opioids (NSOs) are emerging in recreational drug markets worldwide. In particular, 2-benzylbenzimidazole 'nitazene' compounds are problematic NSOs associated with serious clinical consequences, including fatal respiratory depression. Evidence from in vitro studies shows that alkoxy chain length can influence the potency of nitazenes at the mu-opioid receptor (MOR). However, structure-activity relationships (SARs) of nitazenes for inducing opioid-like effects in animal models are not well understood compared to relevant opioids contributing to the ongoing opioid crisis (e.g., fentanyl).
objectivesHere, we examined the in vitro and in vivo effects of nitazene analogues with varying alkoxy chain lengths (i.e., metonitazene, etonitazene, isotonitazene, protonitazene, and butonitazene) as compared to reference opioids (i.e., morphine and fentanyl). METHODS AND
resultsNitazene analogues displayed nanomolar affinities for MOR in rat brain membranes and picomolar potencies to activate MOR in transfected cells. All compounds induced opioid-like effects on locomotor activity, hot plate latency, and body temperature in male mice, and alkoxy chain length markedly influenced potency. Etonitazene, with an ethoxy chain, was the most potent analogue in MOR functional assays (EC
conclusionsOverall, our data show that certain nitazene NSOs are more potent than fentanyl as MOR agonists in mice, highlighting concerns regarding the high potential for overdose in humans who are exposed to these compounds.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.