Beta-caryophyllene

Caryophyllene /ˌkærioʊfɪˈliːn/, or (−)-β-caryophyllene, is a natural bicyclic sesquiterpene that is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of Syzygium aromaticum (cloves), the essential oil of Cannabis sativa, rosemary, and hops. It is usually found as a mixture with isocaryophyllene (the cis double bond isomer) and α-humulene (obsolete name: α-caryophyllene), a ring-opened isomer. Caryophyllene is notable for having a cyclobutane ring, as well as a trans-double bond in a 9-membered ring, both rarities in nature. Caryophyllene /ˌkærioʊfɪˈliːn/, or (−)-β-caryophyllene, is a natural bicyclic sesquiterpene that is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of Syzygium aromaticum (cloves), the essential oil of Cannabis sativa, rosemary, and hops. It is usually found as a mixture with isocaryophyllene (the cis double bond isomer) and α-humulene (obsolete name: α-caryophyllene), a ring-opened isomer. Caryophyllene is notable for having a cyclobutane ring, as well as a trans-double bond in a 9-membered ring, both rarities in nature. The first total synthesis of caryophyllene in 1964 by E.J. Corey was considered one of the classic demonstrations of the possibilities of synthetic organic chemistry at the time. Caryophyllene is one of the chemical compounds that contributes to the aroma of black pepper. 14-Hydroxycaryophyllene oxide (C15H24O2) was isolated from the urine of rabbits treated with (-)-caryophyllene (C15H24). The x-ray crystal structure of 14-hydroxycaryophyllene (as its acetate derivative) has been reported. The metabolism of caryophyllene progresses through (-)-caryophyllene oxide (C15H24O) since the latter compound also afforded 14-hydroxycaryophyllene (C15H24O) as a metabolite. Caryophyllene oxide, in which the olefin of caryophyllene has become an epoxide, is the component responsible for cannabis identification by drug-sniffing dogs and is also an approved food flavoring. The approximate quantity of caryophyllene in the essential oil of each source is given in square brackets (): Caryophyllene is a common sesquiterpene among plant species. It is biosynthesized from the common terpene precursors dimethylallyl pyrophosphate (DMAPP) and isopentenyl pyrophosphate (IPP). First, single units of DMAPP and IPP are reacted via an SN1-type reaction with the loss of pyrophosphate, catalyzed by the enzyme GPPS2, to form geranyl pyrophosphate (GPP). This further reacts with a second unit of IPP, also via an SN1-type reaction catalyzed by the enzyme IspA, to form farnesyl pyrophosphate (FPP). Finally, FPP undergoes QHS1 enzyme-catalyzed intramolecular cyclization to form caryophyllene.