elzasonan elzasonan elzasonan (cp-448,187) is a selective 5-ht1b and 5-ht1d receptor antagonist that was under development by pfizer for the treatment of depression but was discontinued, possibly due to poor efficacy. by preferentially blocking 5-ht1b and 5-ht1d autoreceptors, elzasonan is thought to enhance serotonergic innervations originating from the raphe nucleus, thereby improving signaling to limbic regions like the hippocampus and prefrontal cortex and ultimately resulting in antidepressant effects. elzasonanclinical dataroutes ofadministrationoralatc codenonelegal statuslegal status in general: uncontrolled identifiers iupac name 4-(3,4-dichlorophenyl)-2--thiomorpholin-3-one cas number361343-19-3 yhcl: 220322-05-4 ypubchem cid19544192hcl: 6914152chemspider5290108unii933pjl964rhcl: x38f62rr8l ychemical and physical dataformulac22h23cl2n3osmolar mass448.41 g·mol−13d model (jsmol)interactive image smiles clc4c(cl)cc(n1c(=o)c(\scc1)=c\c3ccccc3n2ccn(c)cc2)cc4 inchi inchi=1s/c22h23cl2n3os/c1-25-8-10-26(11-9-25)20-5-3-2-4-16(20)14-21-22(28)27(12-13-29-21)17-6-7-18(23)19(24)15-17/h2-7,14-15h,8-13h2,1h3/b21-14-key:lhympswmhxuwsk-stzfkdtasa-n (verify)