conorfone conorfone conorfone (inn; tr-5109), also known as conorphone and codorphone, as well as conorphone hydrochloride (usan), is an opioid analgesic that was never marketed. it is an analogue of hydrocodone substituted with an 8-ethyl group and an n-cyclopropylmethyl group. it acts as a mixed agonist-antagonist at the μ-opioid receptor, and is slightly more potent than codeine in analgesic effects but associated with somewhat greater side effects. conorfoneclinical dataatc codenoneidentifiers iupac name (5α,8β)-17-(cyclopropylmethyl)-8-ethyl-3-methoxy-4,5-epoxymorphinan-6-one cas number72060-05-0pubchem cid172964chemspider151049unii9h58696d23chemblchembl2106064chemical and physical dataformulac23h29no3molar mass367.489 g·mol−13d model (jsmol)interactive image smiles o=c45oc1c2c(ccc1oc)cc3n(cc253(cc)c4)cc6cc6 synthesis codorphone synthesis: exposure of thebaine (1) to mild acid leads to hydrolysis of the enol ether function followed by migration of the double bond to yield the conjugated enone (2). addition of lithium diethylcuprate proceeds by 1,4-addition from the less hindered side to give the intermediate 3. treatment of that with cyanogen bromide under von braun reaction conditions leads to the isolable aminocyanide. this is the converted to the secondary amine (4) by treatment with aqueous base. alkylation of that intermediate with cyclopropylmethyl chloride affords the analgesic codorphone (5).