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Palustric Acid
Palustric acid is an organic compound with the formula . It is classified as a diterpenoid (a C20 hydrocarbon with oxygenated groups) and a resin acid. Palustric acid is an isomer of abietic acid: the location of the two C=C bonds differ in these two compounds. It is a colorless solid that is soluble in polar organic solvents. In terms of biological function palustric acid protects its host trees, especially conifers, against insects, an example of plant defense against herbivory. It is biosynthesized from the C20 precursor geranylgeranyl diphosphate Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and diterpenoids. It is also the precursor to carotenoids, gibberellins, tocopherols, and chlorophylls. It is also a precursor to geranylgeranylated proteins, whic .... Safety Palustric acid is very poorly soluble in water and has low acute toxicity.{{cite journal , doi=10.1016/s0043-1354(99)00406-6 , title=Solubility and Toxicity of Resin Acids , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diterpenoid
Diterpenes are a class of terpenes composed of four isoprene units, often with the molecular formula C20H32. They are biosynthesized by plants, animals and fungi via the HMG-CoA reductase pathway, with geranylgeranyl pyrophosphate being a primary intermediate. Diterpenes form the basis for biologically important compounds such as retinol, retinal, and phytol. Some diterpenes are known to be antimicrobial and anti-inflammatory. Structures As with most terpenes a huge number of potential structures exists, which may be broadly divided according to the number of rings present. Biosynthesis Diterpenes are derived from the addition of one IPP unit to FPP to form geranylgeranyl pyrophosphate (GGPP). From GGPP, structural diversity is achieved mainly by two classes of enzymes; the diterpene synthases and cytochromes P450. Several diterpenes are produced by plants and cyanobacteria. GGPP is also the precursor for the synthesis of the phytane by the action of the enzyme geranyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resin Acid
Resin acid refers to any of several related carboxylic acids found in tree resins. Nearly all resin acids have the same basic skeleton: three fused rings having the empirical formula C19H29COOH. Resin acids occur in nature as tacky, yellowish gums consisting of several compounds. They are water-insoluble. A common resin acid is abietic acid. Resin acids are used to produce soaps for diverse applications, but their use is being displaced increasingly by synthetic acids such as 2-ethylhexanoic acid or petroleum-derived naphthenic acids. Botanical analysis Resin acids are protectants and wood preservatives that are produced by parenchymatous epithelial cells that surround the resin ducts in trees from temperate coniferous forests. The resin acids are formed when two-carbon and three-carbon molecules couple with isoprene building units to form monoterpenes (volatile), sesquiterpenes (volatile), and diterpenes (nonvolatile) structures. Pines contain numerous vertical and radial r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abietic Acid
Abietic acid (also known as ''abietinic acid'' or ''sylvic acid'') is a diterpenoid found in coniferous trees. It is supposed to exist to defend the host plant from insect attack or various wounds. Chemically, it is a complicated molecule featuring two alkene groups and a carboxylic acid within a chiral tricyclic framework. As the major component of rosin, it is commercially important. Historically speaking, it was a major component of naval stores. It is the most common of the resin acids. Another common resin acid is pimaric acid, which converts to abietic acid upon heating. Characteristics and occurrence Abietic acid is found in rosin obtained from pine trees. Pure abietic acid is a colorless solid, but commercial samples are usually a glassy or partly crystalline yellowish solid that melts at temperatures as low as . Abietic acid is soluble in alcohols, acetone, and ethers. Its esters and salts are called an abietates, e.g. ethyl abietate and sodium abietate.Lars-Hugo Norlin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Defense Against Herbivory
Plant defense against herbivory or host-plant resistance is a range of adaptations Evolution, evolved by plants which improve their fitness (biology), survival and reproduction by reducing the impact of herbivores. Many plants produce secondary metabolites, known as Heterotelergones, allelochemicals, that influence the behavior, growth, or survival of herbivores. These chemical defenses can act as repellents or toxins to herbivores or reduce plant digestibility. Another defensive strategy of plants is changing their attractiveness. Plant perception (physiology), Plants can sense being touched, and they can respond with strategies to defend against herbivores. Plants alter their appearance by changing their size or quality in a way that prevents overconsumption by large herbivores, reducing the rate at which they are consumed. Other defensive strategies used by plants include escaping or avoiding herbivores at any time in any placefor example, by growing in a location where plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geranylgeranyl Diphosphate
Geranylgeranyl pyrophosphate is an intermediate in the biosynthesis of diterpenes and diterpenoids. It is also the precursor to carotenoids, gibberellins, tocopherols, and chlorophylls. It is also a precursor to geranylgeranylated proteins, which is its primary use in human cells. It is formed from farnesyl pyrophosphate by the addition of an isoprene unit from isopentenyl pyrophosphate. In ''Drosophila'', geranylgeranyl pyrophosphate is synthesised by HMG-CoA encoded by the Columbus gene. Geranylgeranyl pyrophosphate is utilised as a chemoattractant for migrating germ cells that have traversed the midgut epithelia. The attractant signal is produced at the gonadal precursors, directing the germ cells to these sites, where they will differentiate into eggs and spermatozoa (sperm). Related compounds * Farnesyl pyrophosphate * Geranylgeraniol * Geranyl pyrophosphate Geranyl pyrophosphate (GPP), also known as geranyl diphosphate (GDP), is the pyrophosphate ester of the terpenoid g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Acids
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an Substituent, R-group. The general formula of a carboxylic acid is often written as or , sometimes as with R referring to an organyl group (e.g., alkyl, alkenyl, aryl), or hydrogen, or other groups. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They often have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid () is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diterpenes
Diterpenes are a class of terpenes composed of four isoprene units, often with the molecular formula C20H32. They are biosynthesized by plants, animals and fungi via the HMG-CoA reductase pathway, with geranylgeranyl pyrophosphate being a primary intermediate. Diterpenes form the basis for biologically important compounds such as retinol, retinal, and phytol. Some diterpenes are known to be antimicrobial and anti-inflammatory. Structures As with most terpenes a huge number of potential structures exists, which may be broadly divided according to the number of rings present. Biosynthesis Diterpenes are derived from the addition of one IPP unit to FPP to form geranylgeranyl pyrophosphate (GGPP). From GGPP, structural diversity is achieved mainly by two classes of enzymes; the diterpene synthases and cytochromes P450. Several diterpenes are produced by plants and cyanobacteria. GGPP is also the precursor for the synthesis of the phytane by the action of the enzyme geran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenanthrenes
Phenanthrenoids are chemical compounds formed with a phenanthrene backbone. These compounds occur naturally in plants, although they can also be synthesized. Phenanthrols Phenanthrols are any of five isomeric phenols derived from phenanthrene (1-phenanthrol, 2-phenanthrol, 3-phenanthrol, 4-phenanthrol, 9-phenanthrol). These molecules can be biomarkers of smoking and/or PAH worker exposure. Chemistry Under Stilbene photocyclization, UV irradiation, stilbene and its derivatives undergo intramolecular cyclization to form dihydrophenanthrenes. Natural occurrences Phenanthrenes have been reported from flowering plants, mainly in the family Orchidaceae, and a few in the families Dioscoreaceae, Combretaceae and Betulaceae, as well as in the lower plant class Marchantiophyta (liverworts). The rhizome of ''Dioscorea communis'' contains phenanthrenes (7-hydroxy-2,3,4,8-tetramethoxyphenanthrene, 2,3,4-trimethoxy-7,8-methylenedioxyphenanthrene, 3-hydroxy-2,4,-dimethoxy-7,8-methylenedio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood Extracts
Wood is a structural tissue/material found as xylem in the Plant stem, stems and roots of trees and other woody plants. It is an organic materiala natural composite material, composite of cellulose, cellulosic fibers that are strong in tension and embedded in a :wikt:matrix, matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaf, leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fibers. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. Mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
