Wiktionary
tetraterpene
n. (context organic chemistry English) Any terpene formed from eight isoprene units, and having forty carbon atoms; they include the carotene plant pigments.
Wikipedia
Tetraterpene
Tetraterpenes are terpenes consisting of eight isoprene units and have the molecular formula CH. Tetraterpenoids (carotenoids) are tetraterpenes that have been modified by chemical transformations such as oxidation or cyclization.
Tetraterpenes include:
- Phytoene
Biologically important tetraterpenoids include:
- Carotenes and carotenoids, such as the acyclic lycopene, the monocyclic γ-carotene, and the bicyclic α- and β-carotenes
- Xanthophylls, pigments distributed widely in nature