Imidazenil

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Imidazenil
Imidazenil structure.svg
Imidazenil ball-and-stick model.png
Clinical data
ATC code
  • none
Identifiers
  • 6-(2-Bromophenyl)-8-fluoro-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxamide
CAS Number
PubChem CID
ChemSpider
UNII
CompTox Dashboard (EPA)
Chemical and physical data
Formula C18H12BrFN4O
Molar mass 399.223 g·mol−1
3D model (JSmol)
  • Brc4ccccc4C/2=N/Cc1c(ncn1c3c\2cc(F)cc3)C(=O)N
  • InChI=1S/C18H12BrFN4O/c19-13-4-2-1-3-11(13)16-12-7-10(20)5-6-14(12)24-9-23-17(18(21)25)15(24)8-22-16/h1-7,9H,8H2,(H2,21,25) Yes check.svgY
  • Key:OCJHYHKWUWSHEN-UHFFFAOYSA-N Yes check.svgY
   (verify)

Imidazenil [1] is an experimental anxiolytic drug which is derived from the benzodiazepine family, and is most closely related to other imidazobenzodiazepines such as midazolam, flumazenil, and bretazenil.

Imidazenil is a highly potent benzodiazepine receptor partial agonist [2] with an unusual profile of effects, producing some of the effects associated with normal benzodiazepines such as anticonvulsant and anxiolytic effects, yet without any notable sedative or amnestic [3] effects. In fact, imidazenil blocks the sedative effects of diazepam, yet without lowering the convulsion threshold, [4] and so potentially could be a more flexible antidote than the antagonist flumazenil which is commonly used to treat benzodiazepine overdose at present.

Imidazenil has not yet been developed commercially for use in humans, however it has been suggested as a safe and effective treatment for anxiety, [5] a potent yet non-sedating anticonvulsant which might be particularly useful in the treatment of poisoning with organophosphate nerve agents, [6] [7] and as a novel treatment for schizophrenia. [8]

In rats, imidazenil has been demonstrated to have low tolerance or dependence liability, unlike other benzodiazepine receptor agonist ligands, such as diazepam, bretazenil. [9]

See also

Related Research Articles

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Flumazenil is a selective GABAA receptor antagonist administered via injection, otic insertion, or intranasally. Therapeutically, it acts as both an antagonist and antidote to benzodiazepines, through competitive inhibition.

GABA<sub>A</sub> receptor Ionotropic receptor and ligand-gated ion channel

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<span class="mw-page-title-main">Bretazenil</span> Chemical compound

Bretazenil (Ro16-6028) is an imidazopyrrolobenzodiazepine anxiolytic drug which is derived from the benzodiazepine family, and was invented in 1988. It is most closely related in structure to the GABA antagonist flumazenil, although its effects are somewhat different. It is classified as a high-potency benzodiazepine due to its high affinity binding to benzodiazepine binding sites where it acts as a partial agonist. Its profile as a partial agonist and preclinical trial data suggests that it may have a reduced adverse effect profile. In particular bretazenil has been proposed to cause a less strong development of tolerance and withdrawal syndrome. Bretazenil differs from traditional 1,4-benzodiazepines by being a partial agonist and because it binds to α1, α2, α3, α4, α5 and α6 subunit containing GABAA receptor benzodiazepine receptor complexes. 1,4-benzodiazepines bind only to α1, α2, α3 and α5GABAA benzodiazepine receptor complexes.

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References

  1. US 5317018
  2. Thompson DM, Auta J, Guidotti A, Costa E (June 1995). "Imidazenil, a new anxiolytic and anticonvulsant drug, attenuates a benzodiazepine-induced cognition deficit in monkeys". The Journal of Pharmacology and Experimental Therapeutics. 273 (3): 1307–12. PMID   7791102.
  3. Auta J, Faust WB, Lambert P, Guidotti A, Costa E, Moerschbaecher JM (June 1995). "Comparison of the effects of full and partial allosteric modulators of GABA(A) receptors on complex behavioral processes in monkeys". Behavioural Pharmacology. 6 (4): 323–332. doi:10.1097/00008877-199506000-00003. PMID   11224341. S2CID   24584434.
  4. Auta J, Costa E, Davis JM, Guidotti A (September 2005). "Imidazenil: an antagonist of the sedative but not the anticonvulsant action of diazepam". Neuropharmacology. 49 (3): 425–9. doi:10.1016/j.neuropharm.2005.04.005. PMID   15964602. S2CID   44619421.
  5. Atack JR (August 2003). "Anxioselective compounds acting at the GABA(A) receptor benzodiazepine binding site". Current Drug Targets. CNS and Neurological Disorders. 2 (4): 213–32. doi:10.2174/1568007033482841. PMID   12871032.
  6. Rump S, Gidynska T, Galecka E, Antkowiak O, Nawrocka M, Kowalczyk M (2000). "Effects of imidazenil, a new benzodiazepine receptor partial agonist, in the treatment of convulsions in organophosphate intoxications". Neurotoxicity Research. 2 (1): 17–22. doi:10.1007/bf03033323. PMID   15545002. S2CID   2066413.
  7. Auta J, Costa E, Davis J, Guidotti A (March 2004). "Imidazenil: a potent and safe protective agent against diisopropyl fluorophosphate toxicity". Neuropharmacology. 46 (3): 397–403. doi:10.1016/j.neuropharm.2003.09.010. PMID   14975695. S2CID   41221807.
  8. Guidotti A, Auta J, Davis JM, Dong E, Grayson DR, Veldic M, et al. (July 2005). "GABAergic dysfunction in schizophrenia: new treatment strategies on the horizon". Psychopharmacology. 180 (2): 191–205. doi:10.1007/s00213-005-2212-8. PMID   15864560. S2CID   25147595.
  9. Auta J, Giusti P, Guidotti A, Costa E (September 1994). "Imidazenil, a partial positive allosteric modulator of GABAA receptors, exhibits low tolerance and dependence liabilities in the rat". J Pharmacol Exp Ther. 270 (3): 1262–9. PMID   7932179.{{cite journal}}: CS1 maint: multiple names: authors list (link)