umespirone umespirone umespirone (kc-9172) is a drug of the azapirone class which possesses anxiolytic and antipsychotic properties. it behaves as a 5-ht1a receptor partial agonist (ki = 15 nm), d2 receptor partial agonist (ki = 23 nm), and α1-adrenoceptor receptor antagonist (ki = 14 nm), and also has weak affinity for the sigma receptor (ki = 558 nm). unlike many other anxiolytics and antipsychotics, umespirone produces minimal sedation, cognitive/memory impairment, catalepsy, and extrapyramidal symptoms. umespironeclinical dataroutes ofadministrationby mouthatc codenonelegal statuslegal status in general: uncontrolled pharmacokinetic dataelimination half-lifeunknown but effects last much longer than other azapirones, up to 23 hours after a single dose in human clinical studies.identifiers iupac name 3-butyl-7-butyl]-9,9-dimethyl-3,7-diazabicyclononane-2,4,6,8-tetrone cas number107736-98-1pubchem cid65902chemspider59311uniifg0a3vrl5kchemical and physical dataformulac28h40n4o5molar mass512.651 g·mol−13d model (jsmol)interactive image smiles o=c1n(c(=o)c2c(=o)n(c(=o)c1c2(c)c)ccccn4ccn(c3ccccc3oc)cc4)cccc synthesis synthesis: patent:</ref>de3529872 idem uwe schoen, wolfgang kehrbach, werner benson, andreas fuchs, michael ruhland, u.s. patent 4,771,044 (1988 to kali-chemie pharma gmbh).</ref> the condensation between ethyl cyanoacetate (1) and acetone gives ethylisopropylidenecyanoacetate (2). this product is reacted with n-butylcyanoacetamide (3) in sodium methoxide solution to give n-butyl-2,4-dicyano-3,3-dimethylglutarimide, cid:10681941 (4). the glutarimide is cyclized with phosphoric acid to yield 3-butyl-9,9-dimethyl-3,7-diazabicyclononane-2,4,6,8-tetraone, https://pubchem.ncbi.nlm.nih.gov/compound/10825633 cid:10825633 (5). the reaction between 1-(o-anisyl)piperazine (6) and 1,4-dibromobutane (7) gives the quat salt cid:15895413(8). convergent synthesis (in the presence of potassium carbonate) affords umespirone (kc-9172) (9).