Heterocodeine (6-methoxymorphine) is an

opiate An opiate, in classical pharmacology, is a substance derived from opium. In more modern usage, the term ''opioid'' is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain (including antagonis ...

derivative, the 6-

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many ...

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...

morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...

, and a

structural A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such a ...

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

codeine Codeine is an opiate and prodrug of morphine mainly used to treat pain, coughing, and diarrhea. It is also commonly used as a recreational drug. It is found naturally in the sap of the opium poppy, ''Papaver somniferum''. It is typically use ...

; it is called "hetero-" because it is the reverse isomer of codeine. Heterocodeine was first synthesised in 1932 and first patented in 1935. It can be made from morphine by selective methylation. Codeine is the natural mono-methyl ether, but must be metabolized for activity (that is, it is a prodrug). In contrast the semi-synthetic mono-methyl ether, heterocodeine is a direct agonist. The 6,7,8,14 tetradehydro 3,6 methyl di-ether of morphine is

thebaine Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, '' Thēbai'' (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar ...

. Heterocodeine is 6 times more potent than morphine due to having a substitution at the 6-hydroxy position, in a similar manner to 6-acetylmorphine. The drug

methyldihydromorphine Methyldihydromorphine is a semi-synthetic opioid originally developed in Germany in 1936, controlled under both domestic law and UN conventions because of its possible potential for abuse. Methyldihydromorphine is related to heterocodeine and is ...

(dihydroheterocodeine) is a derivative of heterocodeine. Like the morphine metabolite

morphine-6-glucuronide Morphine-6-glucuronide (M6G) is a major active metabolite of morphine. M6G is formed from morphine by the enzyme UGT2B7. It has analgesic effects more potent than morphine. M6G can accumulate to toxic levels in kidney failure. History of discover ...

, 6-position branches (esters or ethers) of morphine bind to the otherwise unagonized human mu receptor subtype mu-3 (or μ3); as well as the 6-acetylmorphine metabolite of heroin this includes heterocodeine. The relative strength of heterocodeine to codeine has been published as 50, 72, 81, 88, 93, 96, and 108 ×. It is not mentioned specifically in the Controlled Substances Act 1970 but is a Schedule II controlled substance as an analogue of

morphinan Morphinan is the prototype chemical structure of a large chemical class of psychoactive drugs, consisting of opiate analgesics, cough suppressants, and dissociative hallucinogens, among others. Structure Morphinan has a phenanthrene core stru ...

under the morphine structure rules of the Analogues Act; in other countries it is usually controlled as a strong opioid. Homocodeine is a synonym for

pholcodine Pholcodine is an opioid cough suppressant (antitussive). It helps suppress unproductive coughs and also has a mild sedative effect, but has little or no analgesic effects. It is also known as morpholinylethylmorphine and homocodeine. Pholcodine is ...

. Bicodeine is a dimer of codeine which is essentially the codeine analogue of

pseudomorphine Pseudomorphine (also known as oxydimorphine or dehydromorphine) is an inactive, natural dimerisation product of the morphine molecule in tandem and thus a common impurity in morphine concentrations. It was first described by Pelletier in 1835. ...

and is also known as pseudocodeine. It is an occasional component of opium and is also a decomposition product of codeine under certain circumstances.

References

{{Opioidergics 4,5-Epoxymorphinans Ethers Mu-opioid receptor agonists Phenols Semisynthetic opioids