Title: Brotizolam
CAS Registry Number: 57801-81-7
CAS Name: 2-Bromo-4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine
Additional Names: 2-bromo-4-(o-chlorophenyl)-9-methyl-6H-thieno[3,2-f]-s-triazolo[4,3-a][1,4]diazepine; 8-bromo-6-(o-chlorophenyl)-1-methyl-4H-s-triazolo[3,4-c]thieno[2,3-e]-1,4-diazepine
Manufacturers' Codes: WE-941-BS
Trademarks: Lendorm (Boehringer, Ing.); Lendormin (Boehringer, Ing.); Mederantil (Boehringer, Ing.); Nimbisan (Solvay); Sintonal (Europharma)
Molecular Formula: C15H10BrClN4S
Molecular Weight: 393.69
Percent Composition: C 45.76%, H 2.56%, Br 20.30%, Cl 9.01%, N 14.23%, S 8.14%
Literature References: One of a class of triazolo-1,4-thienodiazepines having psychotropic activity. Prepn: K. H. Weber et al., DE 2410030; eidem, US 4094984 (1975, 1978 to Boehringer, Ing.); eidem, Ann. 8, 1257 (1978). Pharmacodynamics: J. Gruenberger et al., Curr. Ther. Res. 24, 427 (1978). Bioavailability: B. Saletu et al., Arzneim.-Forsch. 29, 700 (1979). Pharmaco-EEG study: M. Fink, P. Irwin, Clin. Pharmacol. Ther. 30, 336 (1981). Toxicity studies: C. Hewett et al., Arzneim.-Forsch. 36, 592 (1986). Series of articles on pharmacology, pharmacokinetics, toxicology: ibid. 517-620. Veterinary trial as appetite stimulant: A. van Miert et al., J. Vet. Pharmacol. Ther. 12, 147 (1989). Review of pharmacology and clinical efficacy: M. S. Langley, S. P. Clissold, Drugs 35, 104-122 (1988).
Properties: Colorless crystals from ethanol, mp 212-214°. LD50 in mice, rats (mg/kg): >10000, >10000 orally; 920, 1000 i.p. (Hewett).
Melting point: mp 212-214°
Toxicity data: LD50 in mice, rats (mg/kg): >10000, >10000 orally; 920, 1000 i.p. (Hewett)
Therap-Cat: Sedative, hypnotic.
Therap-Cat-Vet: Appetite stimulant.
Keywords: Sedative/Hypnotic; Benzodiazepine Derivatives.
Brovincamine Broxyquinoline Bruceantin Brucine Bryostatins

Systematic (IUPAC) name
Clinical data
AHFS/ International Drug Names
Pregnancy cat.  ?
Legal status Schedule IV (US)
Routes Oral
Pharmacokinetic data
Bioavailability 48-95%
Metabolism Hepatic
Half-life 4.4 hours (range, 2.6–6.9 h)
Excretion Renal
CAS number 57801-81-7 N
ATC code N05CD09
PubChem CID 2451
DrugBank ?
ChemSpider 2357 YesY
KEGG D01744 YesY
Chemical data
Formula C15H10BrClN4S 
Mol. mass 393.7 g/mol
 N (what is this?)  (verify)

Brotizolam[1] (marketed under brand name Lendormin) is a sedative-hypnotic[2] thienodiazepine drug which is a benzodiazepine analog.[3] It possesses anxiolytic, anticonvulsant, hypnotic, sedative and skeletal muscle relaxant properties, and is considered to be similar in effect to short-acting benzodiazepines such as triazolam.[4] It is used in the short term treatment of severe or debilitating insomnia. Brotizolam is an extremely potent drug and has shown anti-anxiety activity at doses as low as .080 to .100 milligrams, but the usual hypnotic dose of brotizolam is 0.125 to 0.25 milligrams,[5] and it is rapidly eliminated with an average half-life of 4.4 hours (range 3.6 - 7.9 hours).[5]

The drug was developed by a team led by T Nishiyama while working for Takeda Chemical Industries in 1976 in Japan.[6]

Brotizolam is not approved for sale in the UK, United States or Canada. It is approved for sale in the Netherlands, Germany, Spain, Belgium, Austria, Portugal, Israel, Italy and Japan.