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Fluorooleic Acid
Fluorooleic acid is a naturally occurring, unsaturated, and fluorinated fatty acid. The Delta notation is 18-F-18:1-delta-9c. Natural occurrence Fluoroleic acid, along with some other ω-fluoro-substituted fatty acids, occurs at about 10–20% in the seed oil of ''Dichapetalum toxicarium'', a plant native to Sierra Leone in West Africa. Biosynthesis Unlike many other plants, ''Dichapetalum toxicarium'' can accumulate much more fluoride, even when the soil content is not particularly high. In young leaves, this is converted into monofluoroacetate, which is stored in the leaves around the flowers. During seed formation, the fluoroacetate is transferred there and converted into long-chain fluorinated fatty acids, including fluorooleic acid. Synthesis One method starts with 8-fluorooctanol, which is first reacted with phosphorus tribromide. The product of this reaction is then reacted with sodium acetylide in xylene/Dimethylformamide, DMF. Then, the reaction takes place with 1-chloro- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an Branched chain fatty acids, unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important diet (nutrition), dietary sources of fuel for animals and important structural components for cell (biology), cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Peroxide
Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use. Concentrated hydrogen peroxide, or "high-test peroxide", decomposes explosively when heated and has been used as both a monopropellant and an oxidizer in rocketry. Hydrogen peroxide is a reactive oxygen species and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly into water and elemental oxygen when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a Stabilizer (chemistry), stabilizer in a weakly acidic solution in an opaque bottle. Hydrogen peroxide is found in biological systems including the human body. Enzymes that u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acids
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important dietary sources of fuel for animals and important structural components for cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oily acid"). Types of fatty acids Fatty acids are classified in many ways: by length, by saturation vs unsat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoroacetic Acid
Fluoroacetic acid is an organofluorine compound with the chemical formula . It is a colorless solid that is noted for its relatively high toxicity. The conjugate base, fluoroacetate occurs naturally in at least 40 plants in Australia, Brazil, and Africa. It is one of only five known organofluorine-containing natural products. Toxicity Fluoroacetic acid is a harmful metabolite of some fluorine-containing drugs (median lethal dose, LD50 = 10 mg/kg in humans). The most common metabolic sources of fluoroacetic acid are fluoroamines and fluoroethers. Fluoroacetic acid can disrupt the Krebs cycle. The metabolite of fluoroacetic acid is Fluorocitric acid and is very toxic because it is not processable using aconitase in the Krebs cycle (where fluorocitrate takes place of citrate as the substrate). The enzyme is inhibited and the cycle stops working. In contrast with fluoroacetic acid, difluoroacetic acid and trifluoroacetic acid are far less toxic. Its p''K''a is 2.66, in contras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorocitric Acid
Fluorocitric acid is an organic compound with the chemical formula . It is a fluorinated carboxylic acid derived from citric acid by substitution of one methylene hydrogen by a fluorine atom. The appropriate anion is called fluorocitrate. Fluorocitrate is formed in two steps from fluoroacetate. Fluoroacetate is first converted to fluoroacetyl-CoA by acetyl-CoA synthetase in the mitochondria. Then fluoroacetyl-CoA condenses with oxaloacetate to form fluorocitrate. This step is catalyzed by citrate synthase. Flurocitrate is a metabolite of fluoroacetic acid and is very toxic because it is not processable using aconitase in the citrate cycle (where fluorocitrate takes place of citrate as the substrate). The enzyme is inhibited and the cycle stops working. See also * Chlorocitric acid * Citric acid * Citrate cycle * Fluoroacetic acid * Fluorooleic acid * Isocitric acid Isocitric acid is a structural isomer of citric acid. Since citric acid and isocitric acid are structural iso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The Science Of Food And Agriculture
The ''Journal of the Science of Food and Agriculture'' is a peer-reviewed scientific journal. It was established in 1950 and is published 15 times a year by John Wiley & Sons on behalf of the Society of Chemical Industry. The journal is included in the Index Medicus (MEDLINE MEDLINE (Medical Literature Analysis and Retrieval System Online, or MEDLARS Online) is a bibliographic database of life sciences and biomedical information. It includes bibliographic information for articles from academic journals covering medic ...). References External links * Agricultural journals Chemical industry in the United Kingdom Wiley (publisher) academic journals Academic journals established in 1950 English-language journals 1950 establishments in the United Kingdom Journals published between 13 and 25 times per year {{agriculture-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Arrest
Cardiac arrest (also known as sudden cardiac arrest [SCA]) is when the heart suddenly and unexpectedly stops beating. When the heart stops beating, blood cannot properly Circulatory system, circulate around the body and the blood flow to the brain and other organs is decreased. When the brain does not receive enough blood, this can cause a person to lose consciousness and brain cells can start to die due to lack of oxygen. Coma and persistent vegetative state may result from cardiac arrest. Cardiac arrest is also identified by a lack of Pulse, central pulses and respiratory arrest, abnormal or absent breathing. Cardiac arrest and resultant hemodynamic collapse often occur due to arrhythmias (irregular heart rhythms). Ventricular fibrillation and ventricular tachycardia are most commonly recorded. However, as many incidents of cardiac arrest occur out-of-hospital or when a person is not having their cardiac activity monitored, it is difficult to identify the specific mechanism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lethal Dose 50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of higher toxicity. The term LD50 is generally attributed to John William Trevan. The test was created by J. W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug botox without animal tests. Conventions The LD50 is usually expressed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer Science & Business Media
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second-largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rat Poison
Rodenticides are chemicals made and sold for the purpose of killing rodents. While commonly referred to as "rat poison", rodenticides are also used to kill mice, groundhog, woodchucks, chipmunks, porcupines, nutria, beavers, and voles. Some rodenticides are lethal after one exposure while others require more than one. Rodents are disinclined to gorge on an unknown food (perhaps reflecting an adaptation to their inability to emesis, vomit), preferring to sample, wait and observe whether it makes them or other rats sick. This phenomenon of poison shyness is the rationale for poisons that kill only after multiple doses. Besides being directly toxic to the mammals that ingest them, including dogs, cats, and humans, many rodenticides present a secondary poisoning risk to animals that hunt or scavenge the dead corpses of rats. Classes of rodenticides Anticoagulants Anticoagulants are defined as chronic (death occurs one to two weeks after ingestion of the lethal dose, rarely soo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Chromatography A
The ''Journal of Chromatography A'' is a peer-reviewed scientific journal publishing research papers in analytical chemistry, with a focus on techniques and methods used for the separation and identification of mixtures. The major difference between ''Journal of Chromatography A'' and ''Journal of Chromatography B'' is the focus being on preparative chromatography instead of analytical chromatography. The split of the Journal of Chromatography into two journals occurred in late 1993, with volume 652 being the first for ''Journal of Chromatography A''. Indexed by ISI the journal received an impact factor of 4.169 as reported in the 2014 Journal Citation Reports by Thomson Reuters, ranking it 15th out of 79 journals in the category "Biochemical Research Methods" and ranking it sixth out of 74 journals in the category "Chemistry, analytical". See also * ''Journal of Chromatography B The ''Journal of Chromatography B'' is a peer-reviewed scientific journal publishing research paper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
