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Leptospermone
Leptospermone is a chemical compound (a β-triketone) produced by some members of the myrtle family ('' Myrtaceae''), such as '' Callistemon citrinus'' (Lemon Bottlebrush), a shrub native to Australia, and ''Leptospermum scoparium'' (Manuka), a New Zealand tree from which it gets its name. Modification of this allelopathic chemical to produce mesotrione led to the commercialization of derivative compounds as HPPD inhibitor herbicides. History Leptospermone was first identified in 1927 and was extracted from a variety of plants in 1965, 1966 and 1968. It was first identified as a chemical in ''Callistemon citrinus'' in California in 1977. A biologist at the Western Research Centre of Stauffer Chemical Company noticed that very few plants grew under ''Callistemon citrinus'' bushes. After taking soil samples and creating an array of extracts, one was identified as an herbicide. While it did have herbicidal effects, the rate required for sufficient coverage was too high to be of prac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesotrione
Mesotrione is the ISO common name for an organic compound that is used as a selective herbicide, especially in maize. A synthetic inspired by the natural substance leptospermone, it inhibits the enzyme 4-hydroxyphenylpyruvate dioxygenase (HPPD) and is sold under brand names including Callisto and Tenacity. It was first marketed by Syngenta in 2001. History The invention of the triketone class of herbicides had its beginnings in an observation in 1977 of allelopathic weed control near a bottlebrush tree, '' Callistemon citrinus''. Chemists at the Stauffer Chemical Company identified the compound responsible as leptospermone, a known natural product which had not previously been reported as having biological activity. Extensive work on analogues led to the discovery and development of sulcotrione and mesotrione. The triketone herbicides were found to be effective on a wide range of commercially-important weed species and to have both pre- and post-emergence activity. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HPPD Inhibitor
4-Hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors (HPPD inhibitors) are a class of herbicides that prevent growth in plants by blocking 4-Hydroxyphenylpyruvate dioxygenase, an enzyme in plants that breaks down the amino acid tyrosine into molecules that are then used by plants to create other molecules that plants need. This process of breakdown, or catabolism, and making new molecules from the results, or biosynthesis, is something all living things do. HPPD inhibitors were first brought to market in 1980, although their mechanism of action was not understood until the late 1990s. They were originally used primarily in Japan in rice production, but since the late 1990s have been used in Europe and North America for corn, soybeans, and cereals, and since the 2000s have become more important as weeds have become resistant to glyphosate and other herbicides. Genetically modified crops are under development that include resistance to HPPD inhibitors. There is a pharmaceutica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callistemon Citrinus
''Melaleuca citrina'', the common red bottlebrush, crimson bottlebrush, or lemon bottlebrush, is a plant in the myrtle family Myrtaceae, and is endemic to eastern Australia. Some Australian state herbaria continue to use the name ''Callistemon citrinus''. It is a hardy and adaptable species, common in its natural habitat. It is widely cultivated, not only in Australia. It was one of the first Australian plants to be grown outside the country, having been taken to England in 1770 by Joseph Banks. Its showy red flower spikes, present over most of the year in an ideal situation, account for its popularity. Description ''Melaleuca citrina'' is a shrub growing to tall but more usually in the range high and wide. It has hard, fibrous or papery bark and its young growth is usually covered with soft, silky hairs. Its leaves are arranged alternately and are long, wide, hard, flat, narrow egg-shaped with the narrower end near the base and with a pointed but not sharp end. There are b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allelopathy
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have beneficial (positive allelopathy) or detrimental (negative allelopathy) effects on the target organisms and the community. Allelopathy is often used narrowly to describe chemically-mediated competition between plants; however, it is sometimes defined more broadly as chemically-mediated competition between any type of organisms. Allelochemicals are a subset of secondary metabolites, which are not directly required for metabolism (i.e. growth, development and reproduction) of the allelopathic organism. Allelopathic interactions are an important factor in determining species distribution and abundance within plant communities, and are also thought to be important in the success of many invasive plants. For specific examples, see black walnut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...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 > 1. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. Terpenes are further 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. History and terminology 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. Previously, many hydrocarbons having the empirical formula C10H16 had been called "camphene", but many other hydrocarbons of the same composition had had different names. Kekulé coined the term "terpene" in order to reduce the confusion. The name "terpene" is a shortened form of "terpentine", an obsolete spelling of "turpentine". Although sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syngenta
Syngenta AG is a provider of agricultural science and technology, in particular seeds and pesticides with its management headquarters in Basel, Switzerland. It is owned by ChemChina, a Chinese state-owned enterprise. Syngenta was founded in 2000 by the merger of the agrichemical businesses of Novartis and AstraZeneca, and acquired by China National Chemical Corporation (ChemChina) in 2017. Its business units are Syngenta Crop Protection, Syngenta Seeds, Adama, and Syngenta Group China. In 2020, the Syngenta Group was formed, bringing together Syngenta, Adama, and the agricultural business of Sinochem under a single entity. Syngenta's primary products include pesticides, selective herbicides, non-selective herbicides, fungicides, insecticides, as well as corn, soya, and biofuel. Syngenta brands include Actara (Thiamethoxam), Agrisure (corn with Viptera trait), Alto (Cyproconazole), Amistar (azoxystrobin), Avicta, Axial, Bicep II, Bravo, Callisto, Celest, Cruiser (TMX, Thiamet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyketide
Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene groups: (-CO-CH2-). First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity. History Naturally produced polyketides by various plants and organisms have been used by humans since before studies on them began in the 19th and 20th century. In 1893, J. Norman Collie synthesized detectable amounts of orcinol by heating dehy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valine
Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α- carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isopropyl group, making it a non-polar aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it: it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, beans and legumes. It is encoded by all codons starting with GU (GUU, GUC, GUA, and GUG). History and etymology Valine was first isolated from casein in 1901 by Hermann Emil Fischer. The name valine comes from valeric acid, which in turn is named after the plant valerian due to the presence of the acid in the roots of the plant. Nomenclature According to IUPAC, carbon atoms forming valine are numbered sequentially s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isobutyryl-CoA
Isobutyryl-coenzyme A is a starting material for many natural products derived from Poly-Ketide Synthase (PKS) assembly lines, as well as PKS-NRPS hybrid assembly lines. These products can often be used as antibiotics. Notably, it is also an intermediate in the metabolism of the amino acid Valine, and structurally similar to intermediates in the catabolism of other small amino acids. See also * Isobutyryl-CoA mutase * Isobutyryl-coenzyme A dehydrogenase deficiency Coenzymes {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesyl Pyrophosphate
Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is an intermediate in the biosynthesis of terpenes and terpenoids such 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, as is shown in the following two steps: * Dimethylallyl pyrophosphate reacts with 3-isopentenyl pyrophosphate to form geranyl pyrophosphate: * Geranyl pyrophosphate then reacts with another molecule of 3-isopentenyl pyrophosphate to form farnesyl pyrophosphate Pharmacology The above reactions are inhibited by bisphosphonates (used for osteoporosis). Farnesyl pyrophosphate is a sel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 unique combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. Sesquiterpenes are found naturally in plants and insects, as semiochemicals, e.g. defensive agents or pheromones. 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 l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
