Methaqualone

Methaqualone
	Skeletal structure of methaqualone
	3D representation of a methaqualone molecule
Clinical data
Pronunciation	/mɛθəˈkweɪloʊn/
Trade names	Quaalude, Sopor, Mandrax
Routes of; administration	Oral, others
Drug class	Sedative; Hypnotic; Anxiolytic; GABAA receptor positive allosteric modulator; Quinazolinone
ATC code	N05CM01 (WHO) ;
Legal status
Legal status	AU: S9 (Prohibited substance); BR: Class F2 (Prohibited psychotropics); CA: Schedule III; DE: Anlage II (Authorized trade only, not prescriptible); NZ: Class B -illegal to possess; UK: Class B; US: Schedule I; UN: Psychotropic Schedule II;
Pharmacokinetic data
Protein binding	70–80%
Elimination half-life	Biphasic (10–40; 20–60 hours)
Identifiers
	IUPAC name 2-Methyl-3-o-tolyl-4(3H)-quinazolinone;; 3,4-Dihydro-2-methyl-4-oxo-3-o-tolylquinazoline;; 2-Methyl-3-(2-methylphenyl)-4-(3H)-quinazolinone;
CAS Number	72-44-6 ;
PubChem CID	6292;
DrugBank	DB04833 ;
ChemSpider	6055 ;
UNII	7ZKH8MQW6T;
KEGG	D00557 ;
ChEBI	CHEBI:6821;
ChEMBL	ChEMBL282052 ;
CompTox Dashboard (EPA)	DTXSID7023279 ;
ECHA InfoCard	100.000.710
Chemical and physical data
Formula	C16H14N2O
Molar mass	250.301 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	113 °C (235 °F)
	SMILES Cc1ccccc1-n1c(C)nc2ccccc2c1=O;
	InChI InChI=1S/C16H14N2O/c1-11-7-3-6-10-15(11)18-12(2)17-14-9-5-4-8-13(14)16(18)19/h3-10H,1-2H3 ; Key:JEYCTXHKTXCGPB-UHFFFAOYSA-N ;
	(verify)

Methaqualone is a sedative-hypnotic medication that was widely prescribed during the mid-20th century. It was marketed under various brand names, including Quaalude (/ˈkweɪluːd/ KWAY-lood) and Sopor, typically containing 300 mg of methaqualone per tablet. A combination drug known as Mandrax was sold primarily in Europe, containing 250 mg of methaqualone and 20 mg of diphenhydramine in a single tablet.

Methaqualone belongs to the quinazolinone class of compounds. Its commercial production was discontinued in many countries during the mid-1980s due to widespread misuse, addiction, and associated public health concerns. However, methaqualone continues to be used as a recreational drug in certain places such as South Africa. In addition, methaqualone analogues with greater than 100-fold potency such as mephenaqualone have emerged as novel designer drugs in the late 2010s and early 2020s.