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Allyl Cyanide
Allyl cyanide is an organic compound with the formula CH2CHCH2CN. Like other small alkyl nitriles, allyl cyanide is colorless and soluble in organic solvents. Allyl cyanide occurs naturally as an antifeedant and is used as a cross-linking agent in some polymers. Synthesis Allyl cyanide is obtained by the reaction of allyl acetate with hydrogen cyanide. A laboratory route to allyl cyanide involves treating allyl bromide with copper(I) cyanide. :CH2=CHCH2Br + CuCN → CH2=CHCH2CN + CuBr Other allyl halides may be used for this reaction including allyl iodide as done by A. Rinne and B. Tollens in 1871 where iodide is a better leaving group than its bromide equivalent and therefore increases the yield. Natural occurrences Allyl cyanide was discovered in 1863 by H. Will and W. Koerner in 1863, they found the compound to be present in mustard oil. The first synthesis of allyl cyanide was reported by A. Claus in 1864. Allyl cyanide is produced in cruciferous vegetables by myrosi ... [...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] |
Antifeedant
Antifeedants are organic compounds produced by plants to repel herbivores through distaste or toxicity. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but instead confer longevity. Antifeedants exhibit a wide range of activities and chemical structures as biopesticides. Examples include rosin, which inhibits attack on trees, and many alkaloids, which are highly toxic to specific insect species, such as quassinoids (extracts from ''Quassia'' trees) against the diamondback moth ('' Plutela xylostella''). ''Samadera indica'' also has quassinoids used for insect antifeedant uses. History "Plant-derived insecticides (e.g., rotenone, veratridines, pyrethrins, and nicotine) have been used for insect control since antiquity." The active ingredients in these plants have been purified and modified. For example, variations on pyrethrin have spawned a large number of synthetic insecticides calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl Acetate
Allyl acetate is an organic compound with formula C3H5OC(O)CH3. This colourless liquid is a precursor to especially allyl alcohol, which is a useful industrial intermediate. It is the acetate ester of allyl alcohol. Preparation Allyl acetate is produced industrially by the gas phase reaction of propene in the presence of acetic acid using a palladium catalyst: :C3H6 + CH3COOH + ½ O2 → CH2=CHCH2OCOCH3 + H2O This method is advantageous because propene is inexpensive and a green chemical. Allyl alcohol is also produced primarily from allyl chloride, but production via the hydrolysis of allyl acetate route avoids the use of chlorine, and so is increasing in use. Vinyl acetate is produced similarly, using ethylene in place of propene. These reactions are examples of acetoxylation. The palladium center is then re-oxidized by the O2 present. The mechanism for the acetoxylation follows a similar pathway, with propene forming a π-allyl bond on the palladium. : Reactions and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl Bromide
Allyl bromide (3-bromopropene) is an organic halide. It is an alkylating agent used in synthesis of polymers, pharmaceuticals, perfumes and other organic compounds. Allyl bromide is a colorless liquid, although commercial samples appear yellow or brown. It is an irritant and a potentially dangerous alkylating agent. Allyl bromide is more reactive but more expensive than allyl chloride, and these considerations guide its use. Preparation Hydrohalogenation Allyl bromide is produced commercially from allyl alcohol and hydrobromic acid: :CH2=CHCH2OH + HBr → CH2=CHCH2Br + H2O It can also be prepared by the halogen-exchange reaction between allyl chloride and hydrobromic acid or by the allylic bromination of propene. Reactions and uses Allyl bromide is an electrophilic alkylating agent. It reacts with nucleophiles, such as amines, carbanions, alkoxides, etc., to introduce the allyl group: :CH2=CHCH2Br + Nu− → CH2=CHCH2Nu + Br− (Nu− is a nucleophile) It is used in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(I) Cyanide
Copper(I) cyanide (cuprous cyanide) is an inorganic compound with the formula CuCN. This off-white solid occurs in two polymorphs; impure samples can be green due to the presence of Cu(II) impurities. The compound is useful as a catalyst, in electroplating copper, and as a reagent in the preparation of nitriles.H. Wayne Richardson "Copper Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Structure Copper cyanide is a coordination polymer. It exists in two polymorphs both of which contain - u-CN chains made from linear copper(I) centres linked by cyanide bridges. In the high-temperature polymorph, HT-CuCN, which is isostructural with AgCN, the linear chains pack on a hexagonal lattice and adjacent chains are off set by +/- 1/3 ''c'', Figure 1. In the low-temperature polymorph, LT-CuCN, the chains deviate from linearity and pack into rippled layers which pack in an AB fashion with chains in adjacent layers rotated by 49 °, Figure 2. File ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mustard Oil
Mustard oil can mean either the pressed oil used for cooking or a pungent essential oil, also known as volatile oil, of the mustard plant. The essential oil results from grinding mustard seed, mixing the grounds with water, and isolating the resulting volatile oil by distillation. It can also be produced by dry distillation of the seed. Pressed mustard oil is used as cooking oil in some cultures; however, sale is restricted in some countries due to high levels of erucic acid. Variations of mustard seeds low in erucic acid have been cultivated at times. History Mustard oil was likely produced in the ancient Jewish town of Huqoq, in modern-day Israel. This is suggested by distinctive agricultural features found there, such as semi-circular wine vats with steep slopes and lower troughs. Scholars believe these structures, dating to Roman Empire, Roman or Byzantine Empire, Byzantine times, were used to crush mustard pods to make oil. Mustard production in Huqoq is also documented in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cruciferous Vegetables
Cruciferous vegetables are vegetables of the family Brassicaceae (also called Cruciferae) with many genera, species, and cultivars being raised for food production such as cauliflower, cabbage, kale, garden cress, bok choy, broccoli, Brussels sprouts, mustard plant and similar green leaf vegetables. The family takes its alternative name (Cruciferae, Neo-Latin for "cross-bearing") from the shape of their flowers, whose four petals resemble a cross. Ten of the most common cruciferous vegetables eaten by people, known colloquially in North America as cole crops and in the UK, Ireland and Australia as brassicas, are in a single species ('' Brassica oleracea''); they are not distinguished from one another taxonomically, only by horticultural category of cultivar groups. Numerous other genera, and species in the family are also edible. Cruciferous vegetables are one of the dominant food crops worldwide. They are best grown in temperatures between 15 to 21° C (59 to 70� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrosinase
Myrosinase (, ''thioglucoside glucohydrolase'', ''sinigrinase'', and ''sinigrase'') is a family of enzymes involved in plant defense against herbivores, specifically the mustard oil bomb. The three-dimensional structure has been elucidated and is available in the PDB (see links in the infobox). A member of the glycoside hydrolase family, myrosinase possesses several similarities with the more ubiquitous O- glycosidases. However, myrosinase is the only known enzyme found in nature that can cleave a thio-linked glucose. Its known biological function is to catalyze the hydrolysis of a class of compounds called glucosinolates. Myrosinase activity Myrosinase is regarded as a defense-related enzyme and is capable of hydrolyzing glucosinolates into various compounds, some of which are toxic. Mechanism Myrosinase catalyzes the chemical reaction :a thioglucoside + H2O \rightleftharpoons a sugar + a thiol Thus, the two substrates of this enzyme are thioglucoside and H2O, whereas it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucosinolates
Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. These natural chemicals most likely contribute to plant defence against pests and diseases, and impart a characteristic bitter flavor property to cruciferous vegetables. Occurrence Glucosinolates occur as secondary metabolites of almost all plants of the order Brassicales. This includes the economically important family Brassicaceae as well as Capparaceae and Caricaceae. Outside of the Brassicales, the genera '' Drypetes'' and '' Putranjiva'' in the family Putranjivaceae, are the only other known occurrence of glucosinolates. Glucosinolates occur in various edible plants such as cabbage (white cabbage, Chinese cabbage, broccoli), Brussels sprouts, watercress, arugula, horseradish, capers, and radishes where the breakdo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperlocomotion
Locomotor activity is a measure of animal behavior which is employed in scientific research. Hyperlocomotion, also known as locomotor hyperactivity, hyperactivity, or increased locomotor activity, is an effect of certain drugs in animals in which locomotor activity (locomotion) is increased. It is induced by certain drugs like psychostimulants and NMDA receptor antagonists and is reversed by certain other drugs like antipsychotics and certain antidepressants. Stimulation of locomotor activity is thought to be mediated by increased signaling in the nucleus accumbens, a major brain area involved in behavioral activation and motivated behavior. Hypolocomotion, also known as locomotor hypoactivity, hypoactivity, and decreased locomotor activity, is an effect of certain drugs in animals in which locomotor activity is decreased. It is a characteristic effect of many sedative agents and general anesthetics. Antipsychotics, which are dopamine receptor antagonists, and many serotonerg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rumen
The rumen, also known as a paunch, is the largest stomach compartment in ruminants. The rumen and the reticulum make up the reticulorumen in ruminant animals. The diverse microbial communities in the rumen allows it to serve as the primary site for microbial fermentation of ingested feed, which is often fiber-rich roughage typically indigestible by mammalian digestive systems. The rumen is known for containing unique microbial networks within its multiple sac compartments to break down nutrients into usable energy and fatty acids. Brief anatomy The rumen is composed of five muscular sacs: cranial sac, ventral sac, dorsal sac, caudodorsal sac, and caudoventral blind sac. Each of these areas contain unique microbial communities, environments, and physical abilities that influence digestion. The outer lining of the rumen, known as the epithelium, serves as a protective layer and contributes to the metabolic processing of fermentation products. The inner lining of the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
