Copaene, or more precisely, α-copaene, is the common (or trivial) chemical name of an oily liquid

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...

that is found in a number of essential oil-producing plants. The name is derived from that of the

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

-producing tropical

copaiba Copaiba is an oleoresin obtained from the trunk of several pinnate-leaved South American leguminous trees (genus ''Copaifera''). The thick, transparent exudate varies in color from light gold to dark brown, depending on the ratio of resin to esse ...

tree, '' Copaifera langsdorffii'', from which the compound was first isolated in 1914. Its structure, including the

chirality Chirality () is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable fro ...

, was determined in 1963. The double-bond isomer with an

exocyclic In organic chemistry, an alicyclic compound contains one or more all-carbon rings which may be either saturated or unsaturated, but do not have aromatic character. Alicyclic compounds may have one or more aliphatic side chains attached. Cyc ...

- methylene group, β-copaene, was first reported in 1967. Chemically, the copaenes are tricyclic

sesquiterpenes Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many combinations. Biochemical modifications s ...

. The molecules are chiral, and the α-copaene

enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...

most commonly found in higher plants exhibits a negative

optical rotation Optical rotation, also known as polarization rotation or circular birefringence, is the rotation of the orientation of the plane of polarization about the optical axis of linearly polarized light as it travels through certain materials. Circul ...

of about −6°. The rare (+)-α-copaene is also found in small amounts in some plants. (+)-α-copaene is of economic significance because it is strongly attracting to an agricultural pest, the Mediterranean fruit fly ''

Ceratitis capitata ''Ceratitis capitata'', commonly known as the Mediterranean fruit fly or medfly, is a yellow-and-brown fly native to sub-Saharan Africa. It has no near relatives in the Western Hemisphere and is considered to be one of the most destructive fru ...

''.

References

{{reflist Alkene derivatives Sesquiterpenes