Caryophyllene

Caryophyllene, or (&minus;)-β-caryophyllene, is a natural bicyclic sesquiterpene that is a constituent of some essential oils, especially clove oil and the oil from the stems and flowers of Syzygium aromaticum. 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, a rarity in nature.

Caryophyllene is one of the chemical compounds that contributes to the spiciness of black pepper.

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.