Title: Flurazepam
CAS Registry Number: 17617-23-1
CAS Name: 7-Chloro-1-[2-(diethylamino)ethyl]-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one
Trademarks: Felmane; Noctosom; Stauroderm
Molecular Formula: C21H23ClFN3O
Molecular Weight: 387.88
Percent Composition: C 65.03%, H 5.98%, Cl 9.14%, F 4.90%, N 10.83%, O 4.12%
Literature References: Prepn: G. A. Archer et al., BE 629005 C.A. 60, 15896f (1964); NL 6401335 C.A. 62, 5289a (1965); G. A. Archer et al., US 3299053 (1963, 1964, 1967 all to Hoffmann-La Roche). Manuf process: R. Fryer, L. H. Sternbach, US 3567710 (1971 to Hoffmann-La Roche). Synthesis: S. Inaba et al., Chem. Pharm. Bull. 19, 263 (1971). Structure-activity studies: L. H. Sternbach et al., J. Med. Chem. 8, 815 (1965); Armagnac et al., Therapie 26, 439 (1971). Metabolism: Schwartz et al., J. Med. Chem. 11, 770 (1968); eidem, J. Pharm. Sci. 59, 1800 (1970). Pharmacology: L. O. Randall et al., Arch. Int. Pharmacodyn. Ther. 178, 216 (1969). Toxicology: H. C. Rosenberg, Pharmacol. Biochem. Behav. 13, 415 (1980). GC determn in plasma: Z. Salama et al., Arzneim.-Forsch. 38, 400 (1988). Comprehensive description: B. C. Rudy, B. Z. Senkowski, Anal. Profiles Drug Subs. 3, 307-331 (1974).
Properties: White rods from ether-petr ether, mp 77-82°.
Melting point: mp 77-82°
Derivative Type: Dihydrochloride
CAS Registry Number: 1172-18-5
Additional Names: Flurazepam hydrochloride
Manufacturers' Codes: Ro-5-6901
Trademarks: Benozil (Kyowa); Dalmadorm (Roche); Dalmane (Roche); Dalmate (Roche); Dormodor (Roche); Felison (Sigurta); Insumin (Kyorin); Lunipax (SKB); Somlan (Sintyal)
Molecular Formula: C21H23ClFN3O.2HCl
Molecular Weight: 460.80
Percent Composition: C 54.74%, H 5.47%, Cl 23.08%, F 4.12%, N 9.12%, O 3.47%
Properties: Pale yellow crystals from methanol + ether, mp 190-220°. LD50 in mice (mg/kg): 290 i.p.; 870 orally; 84 i.v. (Randall).
Melting point: mp 190-220°
Toxicity data: LD50 in mice (mg/kg): 290 i.p.; 870 orally; 84 i.v. (Randall)
NOTE: This is a controlled substance (depressant): 21 CFR, 1308.14.
Therap-Cat: Sedative, hypnotic.
Keywords: Sedative/Hypnotic; Benzodiazepine Derivatives.
Flurogestone Acetate Flurothyl Fluroxene Fluroxypyr Flurprimidol

Systematic (IUPAC) name
Clinical data
Trade names Dalmane
AHFS/Drugs.com monograph
MedlinePlus a682051
Pregnancy cat. X (Contraindicated in pregnancy)
Legal status Schedule IV (US)
Routes Oral
Pharmacokinetic data
Bioavailability 83%
Metabolism Hepatic
Half-life 40–250 hours
Excretion Renal
CAS number 17617-23-1 YesY
ATC code N05CD01
PubChem CID 3393
DrugBank DB00690
ChemSpider 3276 YesY
UNII IHP475989U YesY
KEGG D00329 YesY
Chemical data
Formula C21H23ClFN3O 
Mol. mass 387.88 g/mol
Physical data
Melt. point 79.5 °C (175 °F)
 YesY (what is this?)  (verify)

Flurazepam[1] (marketed under the brand names Dalmane and Dalmadorm) is a drug which is a benzodiazepine derivative. It possesses anxiolytic, anticonvulsant, sedative and skeletal muscle relaxant properties. It produces a metabolite with a very long half-life (40–250 hours), which may stay in the bloodstream for up to four days.[1] Flurazepam is therefore unsuitable as a sleeping medication for some individuals due to next-day sedation; however, this same effect may also provide next-day anxiety relief. For this reason it is sometimes utilized to treat anxiety-induced insomnia on the night before dental visits and other medical procedures, patients are usually instructed to have someone to drive them to and from the appointment when using flurazepam in this context.