Logo of Institute Homepage · The Institute · ChemNet · Chemistry Information · Internet · Index · User Pages



Terpenes are widespread in nature, mainly in plants as constituents of essential oils. Many terpenes are hydrocarbons, but oxygen-containing compounds such as alcohols, aldehydes or ketones (terpenoids) are also found. Their building block is the hydrocarbon isoprene, CH2=C(CH3)-CH=CH2 (isoprene rule, Wallach 1887). Terpene hydrocarbons therefore have molecular formulas (C5H8)n, they are classified according to the number of isoprene units:
                  number of isoprene units
monoterpenes      2
sesquiterpenes    3
diterpenes        4
triterpenes       6
tetraterpenes     8
Examples of monoterpenes are: pinene, nerol, citral, camphor, menthol, limonene. Examples of sesquiterpenes are: nerolidol, farnesol. Examples of diterpenes are: phytol, vitamin A1. Squalene is an example of a triterpene, and carotene (provitamin A1) is a tetraterpene.

Scheme: Formulas of several terpenes


Burkhard Kirste, 1994-08-19, 1998-02-02


deutsche Version  

www@chemie.fu-berlin.de Last modification: 2003-07-31