Terpenoid

Source: Wikipedia, the free encyclopedia.

The terpenoids, also known as isoprenoids, are a class of naturally occurring

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

beta carotene is a terpene derivative called a carotenoid
.

The

isoprenylation. Terpenoids play a role in plant defense as prophylaxis against pathogens and attractants for the predators of herbivores.[6]

Structure and classification

Terpenoids are modified terpenes,[7] wherein methyl groups have been moved or removed, or oxygen atoms added. Some authors use the term "terpene" more broadly, to include the terpenoids. Just like terpenes, the terpenoids can be classified according to the number of isoprene units that comprise the parent terpene:

Terpenoids Analogue terpenes Number of isoprene units Number of carbon atoms General formula Examples[8]
Hemiterpenoids
Isoprene 1 5 C5H8
isovaleric acid, HMBPP, prenol
Monoterpenoids
Monoterpenes 2 10 C10H16 Bornyl acetate, camphor, carvone, citral, citronellal, citronellol, geraniol, eucalyptol, hinokitiol, iridoids, linalool, menthol, thymol
Sesquiterpenoids
Sesquiterpenes 3 15 C15H24 Farnesol, geosmin, humulone
Diterpenoids
Diterpenes 4 20 C20H32 Abietic acid, ginkgolides, paclitaxel, retinol, salvinorin A, sclareol, steviol
Sesterterpenoids
Sesterterpenes
5 25 C25H40 Andrastin A, manoalide
Triterpenoids
Triterpenes 6 30 C30H48 Amyrin, betulinic acid, limonoids, oleanolic acid, sterols, squalene, ursolic acid
Tetraterpenoids
Tetraterpenes 8 40 C40H64 Carotenoids
Polyterpenoid
Polyterpenes >8 >40 (C5H8)n Gutta-percha, natural rubber

Terpenoids can also be classified according to the type and number of cyclic structures they contain: linear, acyclic, monocyclic, bicyclic, tricyclic, tetracyclic, pentacyclic, or macrocyclic.

Salkowski test can be used to identify the presence of terpenoids.[9]

Biosynthesis

Terpenoids, at least those containing an alcohol functional group, often arise by hydrolysis of carbocationic intermediates produced from

diterpenoids, etc.[10]

See also

References

  1. .
  2. .
  3. ^ Firn R (2010). Nature's Chemicals. Oxford: Biology.
  4. .
  5. ^ Specter M (September 28, 2009). "A Life of Its Own". The New Yorker.
  6. PMID 28324581
    .
  7. ^ Houghton, Isaac. "The Physiology of Cannabis Terpenes and Terpenoids – A Brief Overview". Elliot Barker. Retrieved 3 May 2016.
  8. ^ .
  9. .
  10. .

External links