Terpene

Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control.

[4] The term terpene was coined in 1866 by the German chemist August Kekulé to denote all hydrocarbons having the empirical formula C10H16, of which camphene was one.

[9] The 1939 Nobel Prize in Chemistry was awarded to Leopold Ružička "for his work on polymethylenes and higher terpenes",[10][11] "including the first chemical synthesis of male sex hormones.

For example, they play a role in plant defense against herbivory, disease resistance, attraction of mutualists such as pollinators, as well as potentially plant-plant communication.

[2] Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control.

[16] Higher amounts of terpenes are released by trees in warmer weather,[17] where they may function as a natural mechanism of cloud seeding.

For example, termites of the subfamily Nasutitermitinae ward off predatory insects through the use of a specialized mechanism called a fontanellar gun, which ejects a resinous mixture of terpenes.

The possibility that other terpenes could be used as precursors to produce synthetic polymers has been investigated as an alternative to the use of petroleum-based feedstocks.

For example, turpentine, a mixture of terpenes (e.g., pinene), obtained from the distillation of pine tree resin, is used as an organic solvent and as a chemical feedstock (mainly for the production of other terpenoids).

[7] Rosin, another by-product of conifer tree resin, is widely used as an ingredient in a variety of industrial products, such as inks, varnishes and adhesives.

Rosin is also used by violinists (and players of similar bowed instruments) to increase friction on the bow hair, by ballet dancers on the soles of their shoes to maintain traction on the floor, by gymnasts to keep their grips while performing, and by baseball pitchers to improve their control of the baseball.

For example, the aroma and flavor of hops comes, in part, from sesquiterpenes (mainly α-humulene and β-caryophyllene), which affect beer quality.

have similar physical properties but tend to be more polar and hence slightly more soluble in water and somewhat less volatile than their terpene analogues.

IPP and DMAPP are final products of both MVA and MEP pathways and the relative abundance of these two isoprene units is enzymatically regulated in host organisms.

C5 IPP and C5 DMAPP are the end-products in either pathway and are the precursors of terpenoids with various carbon numbers (typically C5 to C40), side chains of (bacterio)chlorophylls, hemes and quinones.

[2][31] Terpenes can be visualized as the result of linking isoprene (C5H8) units "head to tail" to form chains and rings.

Chiral compounds can exist as non-superposable mirror images, which exhibit distinct physical properties such as odor or toxicity.

Di- and trisubstituted alkenes resist polymerization (low ceiling temperatures) but are susceptible to acid-induced carbocation formation.

Others are prepared from those terpenes and terpenoids that are readily isolated in quantity, say from the paper and tall oil industries.