Terpenoid

Terpenoids are a group of natural compounds or related compounds structurally derived from isoprene. Of the terpenes similar, they differ in that they contain functional groups, while there are pure hydrocarbons at terpenes. Similar to the terpenes also the terpenoids according to the number of isoprene units can be divided into groups. The terms terpene and terpenoid, however, in common usage rarely cleanly separated and used very often synonymous with each other.

In terpenoids is a frequent during biosynthesis or more carbon atoms are removed or rearranged, so that the relationship to isoprene is not as clear and does not necessarily present an integer multiple of the five carbon atoms of the isoprene. All terpenoids go but biosynthetically back to the terpenes. Terpenoids are important features for identification of plants, since a certain ingredient pattern is characteristic of a particular plant ( Chemotaxonomy ). There are terpenes including more than 30 000 known terpenoids, some 8,000 of them are pure hydrocarbons and terpenes sense to be so in the narrow counted.

Iridoids

A subclass of terpenoids are the iridoids. They were first found in a species of ant ( Iridomyrmex ).

They consist of a backbone of the Iridodial. Typically, iridoids from ten carbon atoms, ie two Isoprenuntereinheiten, and thus belong to the terpenes. However, there are iridoids with eight and nine carbon atoms, caused by discharge of carbon molecules from the backbone, they belong to the large group of terpenoids.

Polyterpenoide

Prenylquinone are terpenoids with up to ten isoprene units, among them vitamin K, see 1 and 2, vitamin E, plastoquinone and the ubiquinones.