Terpenoid

The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes", terpenoids contain additional functional groups, usually containing oxygen.[1] When combined with the hydrocarbon terpenes, terpenoids comprise about 80,000 compounds.[2] They are the largest class of plant secondary metabolites, representing about 60% of known natural products.[3] Many terpenoids have substantial pharmacological bioactivity and are therefore of interest to medicinal chemists.[4]

Plant terpenoids are used for their aromatic qualities and play a role in traditional herbal remedies. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes.[5] Well-known terpenoids include citral, menthol, camphor, salvinorin A in the plant Salvia divinorum, ginkgolide and bilobalide found in Ginkgo biloba and the cannabinoids found in cannabis. The provitamin beta carotene is a terpene derivative called a carotenoid.

The steroids and sterols in animals are biologically produced from terpenoid precursors. Sometimes terpenoids are added to proteins, e.g., to enhance their attachment to the cell membrane; this is known as isoprenylation. Terpenoids play a role in plant defense as prophylaxis against pathogens and attractants for the predators of herbivores.[6]

  1. ^ Chemistry, International Union of Pure and Applied. IUPAC Compendium of Chemical Terminology. IUPAC. doi:10.1351/goldbook.T06279.
  2. ^ Christianson, David W. (2017). "Structural and Chemical Biology of Terpenoid Cyclases". Chemical Reviews. 117 (17): 11570–11648. doi:10.1021/acs.chemrev.7b00287. PMC 5599884. PMID 28841019.
  3. ^ Firn R (2010). Nature's Chemicals. Oxford: Biology.
  4. ^ Ashour, Mohamed; Wink, Michael; Gershenzon, Jonathan (2010). "Biochemistry of Terpenoids: Monoterpenes, Sesquiterpenes and Diterpenes". Biochemistry of Plant Secondary Metabolism. pp. 258–303. doi:10.1002/9781444320503.ch5. ISBN 9781444320503.
  5. ^ Specter M (September 28, 2009). "A Life of Its Own". The New Yorker.
  6. ^ Singh, Bharat; Sharma, Ram A. (April 2015). "Plant terpenes: defense responses, phylogenetic analysis, regulation and clinical applications". 3 Biotech. 5 (2): 129–151. doi:10.1007/s13205-014-0220-2. ISSN 2190-572X. PMC 4362742. PMID 28324581.