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Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. It is estimated (2006) that 3000 sesquiterpenes have been identified. Biosynthesis and examples The reaction of geranyl pyrophosphate with isopentenyl pyrophosphate results in the 15-carbon farnesyl pyrophosphate (FPP), which is an intermediate in the biosynthesis of sesquiterpenes such as farnesene. Cyclic sesquiterpenes are more common than cyclic monoterpenes because of the increased chain length and additional double bond in the sesquiterpene precursors. In addition to common six-membered ring systems such as the ones found in zingiberene and bisacurone, cyclization of one end of the chain to the other end can lead to macrocyclic rings such as humulene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly Pinophyta, conifers. In plants, terpenes and terpenoids are important mediators of ecological biological interaction, interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control. Terpenes are classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene is a major component of the common solvent, turpentine. The one terpene that has major applications is natural rubber (i.e., polyisoprene). The possibility that other terpenes could be used as precursors to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humulene
Humulene, also known as α-humulene or α-caryophyllene, is a naturally occurring monocyclic sesquiterpene (C15H24), containing an 11-membered ring and consisting of 3 isoprene units containing three nonconjugated C=C double bonds, two of them being triply substituted and one being doubly substituted. It was first found in the essential oils of '' Humulus lupulus'' (hops), from which it derives its name. Humulene is an isomer of β-caryophyllene, and the two are often found together as a mixture in many aromatic plants. Occurrence Humulene is one of the components of the essential oil from the flowering cone of the hops plant, '' Humulus lupulus'', from which it derives its name. The concentration of humulene varies among different varieties of the plant but can be up to 40% of the essential oil. Humulene and its reaction products in the brewing process of beer gives many beers their “hoppy” aroma. Noble hop varieties have been found to have higher levels of humulene, whil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caryophyllene
Caryophyllene (), more formally (−)-β-caryophyllene (BCP), is a natural bicyclic sesquiterpene that occurs widely in nature. Caryophyllene is notable for having a cyclobutane ring, as well as a ''trans''-double bond in a 9-membered ring, both rarities in nature. Production Caryophyllene can be produced synthetically, but it is invariably obtained from natural sources because it is widespread. It is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of ''Syzygium aromaticum'' (cloves), the essential oil of ''Cannabis sativa'', copaiba, rosemary, and hops. It is usually found as a mixture with isocaryophyllene (the ''cis'' double bond isomer) and humulene, α-humulene (obsolete name: α-caryophyllene), a ring-opened isomer. Caryophyllene is one of the chemical compounds that contributes to the odor, aroma of black pepper. Basic research β-Caryophyllene is under basic research for its potential action as an agonist of the cannab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patchoulol
Patchoulol or patchouli alcohol (C15H26O) is a sesquiterpene alcohol found in patchouli. Patchouli oil is an important material in perfumery. The (−)-optical isomer is one of the organic compounds responsible for the typical patchouli scent. Patchoulol is obtained by fermentation of leaves of ''Pogostemon cablin''. Patchoulol is also used in the synthesis of the chemotherapy drug Taxol. Structure determination Gal first isolated patchouli alcohol in 1869, and Montgolfier later formulated its chemical composition (correctly) as C15H26O. Early structural investigation soon established the presence of a saturated tricyclic tertiary alcohol. After several years of careful degradation study, George Büchi, Büchi and co-workers proposed that patchouli alcohol had the structure 1. A subsequent synthesis of material which corresponded to an authentic sample of natural patchouli alcohol appeared to verify Büchi's proposal. However, Jack D. Dunitz, Dunitz and co-workers serendipitou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesyl Pyrophosphate
Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is the precursor to all sesquiterpenes, which comprises thousands of compounds. These include all sesquiterpenes as well as sterols and carotenoids. It is also used in the synthesis of CoQ (part of the electron transport chain), as well as dehydrodolichol diphosphate (a precursor of dolichol, which transports proteins to the ER lumen for ''N''-glycosylation). Biosynthesis Farnesyl pyrophosphate synthase (a prenyl transferase) catalyzes sequential condensation reactions of dimethylallyl pyrophosphate with 2 units of 3-isopentenyl pyrophosphate to form farnesyl pyrophosphate: : Pharmacology The above reactions are inhibited by bisphosphonates (used for osteoporosis). Farnesyl pyrophosphate is a selective agonist of TRPV3. Related compounds * Farnesene * Farnesol * Geranyl pyrophosphate *Geranylgeranyl pyrophosphate Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoterpenes
Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen functionality or missing a methyl group, are called monoterpenoids. Monoterpenes and monoterpenoids are diverse. They have relevance to the pharmaceutical, cosmetic, agricultural, and food industries. Biosynthesis Monoterpenes are derived biosynthetically from units of isopentenyl pyrophosphate, which is formed from acetyl-CoA via the intermediacy of mevalonic acid in the HMG-CoA reductase pathway. An alternative, unrelated biosynthesis pathway of IPP is known in some bacterial groups and the plastids of plants, the so-called MEP-(2-methyl-D-erythritol-4-phosphate) pathway, which is initiated from C5 sugars. In both pathways, IPP is isomerized to DMAPP by the enzyme isopentenyl pyrophosphate isomerase. Geranyl pyrophosphate is the precurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadinene
Cadinenes are a group of isomeric hydrocarbons that occur in a wide variety of essential oil-producing plants. The name is derived from that of the Cade juniper (''Juniperus oxycedrus'' L.), the wood of which yields an oil from which cadinene isomers were first isolated. Chemically, the cadinenes are bicyclic sesquiterpenes. The term ''cadinene'' has sometimes also been used in a broad sense to refer to any sesquiterpene with the so-called cadalane (4-isopropyl-1,6-dimethyldecahydronaphthalene) carbon skeleton. Because of the large number of known double-bond and stereochemical isomers, this class of compounds has been subdivided into four subclasses based on the relative stereochemistry at the isopropyl group and the two bridgehead carbon atoms. The name ''cadinene'' is now properly used only for the first subclass below, which includes the compounds originally isolated from cade oil. Only one enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmə ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zingiberene
Zingiberene is a cyclic compound, monocyclic sesquiterpene that is the predominant constituent of the oil of ginger (''Zingiber officinale''), from which it gets its name. It can contribute up to 30% of the Essential oil, essential oils in ginger Rhizome, rhizomes. This is the compound that gives ginger its distinct flavoring. Biosynthesis Zingiberene is formed in the isoprenoid pathway from farnesyl pyrophosphate (FPP). FPP undergoes a rearrangement to give nerolidyl diphosphate. After the removal of pyrophosphate, the ring closes leaving a carbocation on the tertiary carbon attached to the ring. A 1,3-hydride shift then takes place to give a more stable allylic carbocation. The final step in the formation of zingiberene is the removal of the cyclic allylic proton and consequent formation of a double bond. Zingiberene synthase is the enzyme responsible for catalyzing the reaction forming zingiberene as well as other mono- and sesquiterpenes. See also * Gingerol * sequiphellandre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesene
The term farnesene refers to a set of six closely related chemical compounds which all are sesquiterpenes. α-Farnesene and β-farnesene are isomers, differing by the location of one double bond. α-Farnesene is 3,7,11-trimethyl-1,3,6,10-dodecatetraene and β-farnesene is 7,11-dimethyl-3-methylene-1,6,10-dodecatriene. The alpha form can exist as four stereoisomers that differ about the geometry of two of its three internal double bonds (the stereoisomers of the third internal double bond are identical). The beta isomer exists as two stereoisomers about the geometry of its central double bond. Two of the α-farnesene stereoisomers are reported to occur in nature. (''E'',''E'')-α-Farnesene is the most common isomer. It is found in the coating of apples, and other fruits, and it is responsible for the characteristic green apple odour. Its oxidation by air forms compounds that are damaging to the fruit. The oxidation products injure cell membranes which eventually causes cell dea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadinene
Cadinenes are a group of isomeric hydrocarbons that occur in a wide variety of essential oil-producing plants. The name is derived from that of the Cade juniper (''Juniperus oxycedrus'' L.), the wood of which yields an oil from which cadinene isomers were first isolated. Chemically, the cadinenes are bicyclic sesquiterpenes. The term ''cadinene'' has sometimes also been used in a broad sense to refer to any sesquiterpene with the so-called cadalane (4-isopropyl-1,6-dimethyldecahydronaphthalene) carbon skeleton. Because of the large number of known double-bond and stereochemical isomers, this class of compounds has been subdivided into four subclasses based on the relative stereochemistry at the isopropyl group and the two bridgehead carbon atoms. The name ''cadinene'' is now properly used only for the first subclass below, which includes the compounds originally isolated from cade oil. Only one enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmə ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zingiberene
Zingiberene is a cyclic compound, monocyclic sesquiterpene that is the predominant constituent of the oil of ginger (''Zingiber officinale''), from which it gets its name. It can contribute up to 30% of the Essential oil, essential oils in ginger Rhizome, rhizomes. This is the compound that gives ginger its distinct flavoring. Biosynthesis Zingiberene is formed in the isoprenoid pathway from farnesyl pyrophosphate (FPP). FPP undergoes a rearrangement to give nerolidyl diphosphate. After the removal of pyrophosphate, the ring closes leaving a carbocation on the tertiary carbon attached to the ring. A 1,3-hydride shift then takes place to give a more stable allylic carbocation. The final step in the formation of zingiberene is the removal of the cyclic allylic proton and consequent formation of a double bond. Zingiberene synthase is the enzyme responsible for catalyzing the reaction forming zingiberene as well as other mono- and sesquiterpenes. See also * Gingerol * sequiphellandre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
