sl-164 sl-164 sl-164, also known as dicloqualone or dcq is an analogue of methaqualone developed in the late 1960s by a team at sumitomo. sl-164 has similar sedative, hypnotic and anticonvulsant properties to the parent compound, but was never marketed for clinical use. sl-164clinical dataatc codenoneidentifiers iupac name 5-chloro-3-(4-chloro-2-methylphenyl)-2-methylquinazolin-4-one cas number3476-88-8 ypubchem cid63386chemspider57049uniikq54t3ql7xcomptox dashboard (epa)dtxsid60188313 chemical and physical dataformulac16h12cl2n2omolar mass319.185 g·mol−13d model (jsmol)interactive image smiles clc1=cc(c)=c(n2c(c)=nc3=cc=cc(cl)=c3c2=o)c=c1 inchi inchi=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,1-2h3key:kuihlohnugocto-uhfffaoysa-n