:SL-164

{{short description|Chemical compound}}

{{Infobox drug

| IUPAC_name = 5-chloro-3-(4-chloro-2-methylphenyl)-2-methylquinazolin-4-one

| image = SL-164.svg

| width = 200

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| CAS_number_Ref = {{cascite|correct|CAS}}

| CAS_number = 3476-88-8

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = KQ54T3QL7X

| ATC_prefix = none

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| PubChem = 63386

| ChemSpiderID = 57049

| C=16 | H=12 | Cl=2 | N=2 | O=1

| smiles = ClC1=CC(C)=C(N2C(C)=NC3=CC=CC(Cl)=C3C2=O)C=C1

| StdInChI = 1S/C16H12Cl2N2O/c1-9-8-11(17)6-7-14(9)20-10(2)19-13-5-3-4-12(18)15(13)16(20)21/h3-8H,1-2H3

| StdInChIKey = KUIHLOHNUGOCTO-UHFFFAOYSA-N

}}

SL-164, also known as dicloqualone or DCQ, is an analogue of methaqualone developed in the late 1960s by a team at Sumitomo.{{cite patent | country = US | number = 3651230 | title = Compositions And Methods For Tranquilizing With Substituted 3-Phenyl-4-Quinazolinone Derivatives }} SL-164 has similar sedative, hypnotic{{cite journal | vauthors = Saito C, Sakai S, Yukawa Y, Yamamoto H, Takagi H | title = Pharmacological studies on 2-methyl-3(2'-methyl-4'-chlorophenyl)-5-chloro-4[H)-quinazolinone (SL-164) | journal = Arzneimittel-Forschung | volume = 19 | issue = 12 | pages = 1945–9 | date = December 1969 | pmid = 4985336 }} and properties to the parent compound, but was never marketed for clinical use, due to higher risk of convulsions. Like other 4-substituted analogues, such as methylmethaqualone, SL-164 may cause seizures.{{cite journal | vauthors = Boltze KH, Dell HD, Lehwald H, Lorenz D, Rueberg-Schweer M | title = [Substituted 4-Quinazolinone Derivatives As Hypnotics] | language = German | journal = Arzneimittel-Forschung | volume = 13 | pages = 688–701 | date = August 1963 | pmid = 14085923 }}