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2,5-Dimethoxy-p-cymene
2,5-Dimethoxy-''p''-cymene, or thymohydroquinone dimethyl ether, is a phytochemical found in the essential oils of plants within the family ''Asteraceae''. These essential oils, which contain the compound as a major component of the oil, have antifungal, antibacterial, and insecticidal properties. Natural occurrence 2,5-Dimethoxy-''p''-cymene occurs in a variety of different plants' essential oils. Examples include: * ''Ayapana triplinervis'' (92.8%) * ''Apium leptophyllum'' (50.7 to 80.24%) * '' Cyathocline purpurea'' (57.4%) * ''Arnica montana'' (32.6%) * '' Laggera crispata'' (32.2%) * '' Blumea perrottetiana'' (30.0%) * ''Eupatorium capillifolium'' (20.8%) * '' Sphaeranthus indicus'' (18.2%) * '' Limbarda crithmoides'' (16.4) * '' Bubonium imbricatum'' (16.2%) Chemical synthesis 2,5-Dimethoxy-''p''-cymene can be synthesized from carvacrol by aromatic halogenation followed by nucleophilic substitution with sodium methoxide and Williamson ether synthesis using methyl iodide. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymoquinone
Thymoquinone is a phytochemical compound found in the plant ''Nigella sativa''. It is also found in select cultivated ''Monarda fistulosa'' plants which can be steam distilled to produce an essential oil. It has been classified as a pan-assay interference compound, which binds indiscriminately to many proteins. It is under preliminary research to identify its possible biological properties. See also * Dithymoquinone, a dimer Dimer may refer to: * Dimer (chemistry), a chemical structure formed from two similar sub-units ** Protein dimer, a protein quaternary structure ** d-dimer * Dimer model, an item in statistical mechanics, based on ''domino tiling'' * Julius Dimer ... of thymoquinone * 2,5-Dimethoxy-''p''-cymene References {{reflist 1,4-Benzoquinones Monoterpenes Isopropyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ayapana Triplinervis
''Ayapana triplinervis'' (aya-pana, water hemp) is a tropical American shrub in the family Asteraceae. This plant has long slender leaves which are often used in traditional medicine. The flowers are pale pink and the thin, hairless stem is reddish in color. Description ''Ayapana triplinervis'' is an ascending, slender perennial. Its leaves are purple, subsessile, lanceolate, 3-nerved, acuminate, subentire, and glabrous. Inflorescence is a lax, few-headed corymb, heads pedicellate, about 20-flowered. Flowers are slaty blue. Chemical constituents ''Ayapana triplinervis'' is a source of several coumarin derivatives. The leaves contain a volatile essential oil, ayapana oil, 1.14%. This oil contains the coumarins ayapanin (herniarin) and ayapin, as well as other chemical compounds including stigmasterol, vitamin C, and carotene. The essential oil also contains thymohydroquinone dimethyl ether. The plant yields cineol, α-phellandrene, alpha-terneol, ayapanin, ayapin, bor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arnica Montana
''Arnica montana'', also known as wolf's bane, leopard's bane, mountain tobacco and mountain arnica, is a moderately toxic European flowering plant in the daisy family Asteraceae. It is noted for its large yellow flower head. The names "wolf's bane" and "leopard's bane" are also used for another plant, aconitum, which is extremely poisonous. ''Arnica montana'' is used as an herbal medicine for analgesic and anti-inflammatory purposes, but there is insufficient high-quality clinical evidence for such effects, and it is toxic when taken internally or applied to injured skin. Description ''Arnica montana'' is a flowering plant about tall aromatic fragrant, herbaceous perennial. Its basal green ovate leaves with rounded tips are bright coloured and level to the ground. In addition, they are somewhat downy on their upper surface, veined and aggregated in rosettes. By contrast, the upper leaves are opposed, spear-shaped and smaller which is an exception within the Asteraceae. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytochemical
Phytochemicals are chemical compounds produced by plants, generally to help them resist fungi, bacteria and plant virus infections, and also consumption by insects and other animals. The name comes . Some phytochemicals have been used as poisons and others as traditional medicine. As a term, ''phytochemicals'' is generally used to describe plant compounds that are under research with unestablished effects on health, and are not scientifically defined as essential nutrients. Regulatory agencies governing food labeling in Europe and the United States have provided guidance for industry to limit or prevent health claims about phytochemicals on food product or nutrition labels. Definition Phytochemicals are chemicals of plant origin. Phytochemicals (from Greek ''phyto'', meaning "plant") are chemicals produced by plants through primary or secondary metabolism. They generally have biological activity in the plant host and play a role in plant growth or defense against competitors, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bubonium Imbricatum
''Asteriscus'' is a genus of flowering plants in the family Asteraceae. Species ; Species formerly included Several species have been transferred to ''Pallenis'' or ''Rhanterium'', most notably: * '' Asteriscus maritimus'' (L.) Less., synonym of ''Pallenis maritima'' (L.) Greuter Distribution The genus is native to Europe, North Africa, Macaronesia, and the Middle East The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro .... includes photos and European distribution maps References Bibliography # # ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticides
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain. Insecticides can be classified into two major groups: systemic insecticides, which have residual or long term activity; and contact insecticides, which have no residual activity. The mode of action describes how the pesticide kills or inactivates a pest. It provides another way of classifying insecticides. Mode of action can be important in understanding whether an insecticide will be toxic to unrelated species, such as fish, birds and mammals. Insecticides may be repellent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungicides
Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. A fungistatic inhibits their growth. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, and profit. Fungicides are used both in agriculture and to fight fungal infections in animals. Chemicals used to control oomycetes, which are not fungi, are also referred to as fungicides, as oomycetes use the same mechanisms as fungi to infect plants. Fungicides can either be contact, translaminar or systemic. Contact fungicides are not taken up into the plant tissue and protect only the plant where the spray is deposited. Translaminar fungicides redistribute the fungicide from the upper, sprayed leaf surface to the lower, unsprayed surface. Systemic fungicides are taken up and redistributed through the xylem vessels. Few fungicides move to all parts of a plant. Some are locally systemic, and some move upwardly. Most fungicides that can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroquinone Ethers
Hydroquinone, also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2. It has two hydroxyl groups bonded to a benzene ring in a ''para'' position. It is a white granular solid. Substituted derivatives of this parent compound are also referred to as hydroquinones. The name "hydroquinone" was coined by Friedrich Wöhler in 1843. Production Hydroquinone is produced industrially in two main ways.Phillip M. Hudnall "Hydroquinone" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. 2005 Wiley-VCH, Weinheim. . * The most widely used route is similar to the cumene process in reaction mechanism and involves the dialkylation of benzene with propene to give 1,4-diisopropylbenzene. This compound reacts with air to afford the bis(hydroperoxide), which is structurally similar to cumene hydroperoxide and rearranges in acid to give acetone and hydroquinone. * A se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Iodide
Iodomethane, also called methyl iodide, and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. It is a dense, colorless, volatile liquid. In terms of chemical structure, it is related to methane by replacement of one hydrogen atom by an atom of iodine. It is naturally emitted by rice plantations in small amounts. It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans, and in lesser amounts on land by terrestrial fungi and bacteria. It is used in organic synthesis as a source of methyl groups. Preparation and handling Iodomethane is formed via the exothermic reaction that occurs when iodine is added to a mixture of methanol with red phosphorus. The iodinating reagent is phosphorus triiodide that is formed ''in situ:'' :3 CH3OH + PI3 → 3 CH3I + H2PO3H Alternatively, it is prepared from the reaction of dimethyl sulfate with potassium iodide in the presence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Williamson Ether Synthesis
The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol ( alkoxide). This reaction was developed by Alexander Williamson in 1850. Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an SN2 reaction. This reaction is important in the history of organic chemistry because it helped prove the structure of ethers. The general reaction mechanism is as follows: An example is the reaction of sodium ethoxide with chloroethane to form diethyl ether and sodium chloride: :C2H5Cl + C2H5ONa -> C2H5OC2H5 + NaCl Mechanism The Williamson ether reaction follows an SN2 bimolecular nucleophilic substitution mechanism. In an SN2 reaction mechanism there is a backside attack of an electrophile by a nucleophile and it occurs in a concerted mechanism (happens all at once). In order for the SN2 reaction to take place there must be a good leaving group which is strongly electronegative, commonly a hali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Methoxide
Sodium methoxide is the simplest sodium alkoxide. With the formula , it is a white solid, which is formed by the deprotonation of methanol. Itis a widely used reagent in industry and the laboratory. It is also a dangerously caustic base. Preparation and structure Sodium methoxide is prepared by treating methanol with sodium: : The reaction is so exothermic that ignition is possible. The resulting solution, which is colorless, is often used as a source of sodium methoxide, but the pure material can be isolated by evaporation followed by heating to remove residual methanol. As a solid, sodium methoxide is polymeric, with sheet-like arrays of centers, each bonded to four oxygen centers. The structure, and hence the basicity, of sodium methoxide in solution depends on the solvent. It is a significantly stronger base in DMSO where it is more fully ionized and free of hydrogen bonding. Applications Organic synthesis Sodium methoxide is a routinely used base in organic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
