cyclopentobarbital cyclopentobarbital cyclopentobarbital sodium (cyclopal, dormisan) is a barbiturate derivative invented in the 1940s. it has sedative and anticonvulsant properties, and was used primarily as an anaesthetic in veterinary medicine. cyclopal is considered similar in effects to phenobarbital but lasts almost three times as long, and is considered a long-acting barbiturate with a fairly slow onset of action. cyclopentobarbitalclinical dataother namesallylpental, cyclopental, 5-allyl-5-δ2-cyclopentenyl barbituric acidatc codenonelegal statuslegal status ca: schedule iv identifiers iupac name 5-(1-cyclopent-2-enyl)-5-prop-2-enyl-1,3-diazinane-2,4,6-trione cas number76-68-6 302-34-1 (sodium salt)pubchem cid6454chemspider6212 yunii2230xwg55qecha infocard100.000.891 chemical and physical dataformulac12h14n2o3molar mass234.255 g·mol−13d model (jsmol)interactive image smiles o=c1nc(=o)nc(=o)c1(c2/c=c\cc2)c\c=c inchi inchi=1s/c12h14n2o3/c1-2-7-12(8-5-3-4-6-8)9(15)13-11(17)14-10(12)16/h2-3,5,8h,1,4,6-7h2,(h2,13,14,15,16,17) ykey:xovjaynmqdtijd-uhfffaoysa-n y (verify)