• 7-chloro-5-methyl-3-(5-propan-2-yl-1,2,4-oxadiazol-3-yl)-4H-imidazo[1,5-a][1,4]benzodiazepin-6-one
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass357.80 g·mol−1
3D model (JSmol)
  • Clc4cccc3n2cnc(c1nc(on1)C(C)C)c2CN(C(=O)c34)C
  • InChI=1S/C17H16ClN5O2/c1-9(2)16-20-15(21-25-16)14-12-7-22(3)17(24)13-10(18)5-4-6-11(13)23(12)8-19-14/h4-6,8-9H,7H2,1-3H3 checkY
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FG-8205[1] (L-663,581) is an imidazobenzodiazepine derivative related to bretazenil, which acts as a partial agonist at GABAA receptors, with slight selectivity for the α1-containing subtype. In animal tests it has anxiolytic and anticonvulsant effects but with little sedation or ataxia produced.[2][3][4][5]

See also


  1. ^ Watjen F, Baker R, Engelstoff M, Herbert R, MacLeod A, Knight A, Merchant K, Moseley J, Saunders J, Swain CJ (October 1989). "Novel benzodiazepine receptor partial agonists: oxadiazolylimidazobenzodiazepines". J. Med. Chem. 32 (10): 2282–91. doi:10.1021/jm00130a010. PMID 2552115.
  2. ^ Tricklebank MD, Honoré T, Iversen SD, Kemp JA, Knight AR, Marshall GR, Rupniak NM, Singh L, Tye S, Watjen F (November 1990). "The pharmacological properties of the imidazobenzodiazepine, FG 8205, a novel partial agonist at the benzodiazepine receptor". Br. J. Pharmacol. 101 (3): 753–61. doi:10.1111/j.1476-5381.1990.tb14152.x. PMC 1917729. PMID 1963808.
  3. ^ Lin JH, Chen IW, Lin TH (December 1994). "Blood–brain barrier permeability and in vivo activity of partial agonists of benzodiazepine receptor: a study of L-663,581 and its metabolites in rats". J. Pharmacol. Exp. Ther. 271 (3): 1197–202. PMID 7996426.
  4. ^ Guscott MR, Cook GP, Bristow LJ (September 2000). "Contextual fear conditioning and baseline startle responses in the rat fear-potentiated startle test: a comparison of benzodiazepine/gamma-aminobutyric acid-A receptor agonists". Behav Pharmacol. 11 (6): 495–504. doi:10.1097/00008877-200009000-00006. PMID 11103915. S2CID 33999227.
  5. ^ Atack JR (August 2003). "Anxioselective compounds acting at the GABA(A) receptor benzodiazepine binding site". Curr Drug Targets CNS Neurol Disord. 2 (4): 213–32. doi:10.2174/1568007033482841. PMID 12871032.