5579. Lorazepam

Nomenclature

CAS number: 846-49-1
7-Chloro-5-(2-chlorophenyl)-1,3-dihydro-3-hydroxy-2H-1,4-benzodiazepin-2-one; Wy-4036; Ativan (Wyeth); Emotival (Armstrong); Lorax (Wyeth); Lorsilan (Belupo); Pro Dorm (Synthelabo); Psicopax (Schering); Punktyl (Krewel); Quait (SIT); Sedatival (Raffo); Sedazin (Lagap); Somagerol (Brenner-Efeka); Tavor (Wyeth); Temesta (Wyeth); Wypax (Yamanouchi).
C15H10Cl2N2O2; mol wt 321.16.
C 56.10%, H 3.14%, Cl 22.08%, N 8.72%, O 9.96%.

Description and references

Prepn: S. C. Bell, BE 621819; idem, US 3296249 (1963, 1967 both to Am. Home Prod.); and structure-activity study: idem et al., J. Med. Chem. 11, 457 (1968). Determn by HPLC: I. Jane, A. McKinnon, J. Chromatogr. 323, 191 (1985). Series of articles on pharmacology, metabolism, clinical studies: Arzneim.-Forsch. 21, 1047-1102 (1971). Toxicity study: G. Owen et al., ibid. 1065. Comprehensive description: J. G. Rutgers, C. M. Shearer, Anal. Profiles Drug Subs. 9, 397-426 (1980). Review of clinical pharmacology and therapeutic use: B. Ameer, D. J. Greenblatt, Drugs 21, 161-200 (1981). Clinical trial to prevent recurrent alcohol-related seizures: G. D'Onofrio et al., N. Engl. J. Med. 340, 915 (1999).

Chemical structure

Properties

Crystals, mp 166-168°. uv max (methanol): 229 nm, (1N NaOH): 233 nm, (1N HCl): 237 nm. Soly (mg/ml): water 0.08, chloroform 3, alcohol 14, propylene glycol 16, ethyl acetate 30. pK1 1.3; pK2 11.5. LD50 in mice, rats (mg/kg): 3178, >5000 orally (Owen).

Note

This is a controlled substance (depressant): 21 CFR, 1308.14.

Therapeutic Category

Anxiolytic; anticonvulsant.

Keywords

Anxiolytic; Benzodiazepine Derivatives; Anticonvulsant