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Xanthone
Xanthone is an organic compound with the molecular formula O[C6H4]2CO. It is a white solid. In 1939, xanthone was introduced as an insecticide and it currently finds uses as Insecticide, ovicide for codling moth eggs and as a larvicide. Xanthone is also used in the preparation of xanthydrol, which is used in the determination of urea levels in the blood. It can also be used as a photocatalyst. Synthesis Xanthone can be prepared by the heating of phenyl salicylate: Six methods have been reported for synthesizing xanthone derivatives: *The Michael-Kostanecki method uses an equimolar mix of a polyphenol and an ''O''-hydroxybenzoic acid, which are heated with a dehydration reaction, dehydrating agent. *The Friedel–Crafts reaction, Friedel-Crafts method has a benzophenone intermediate. *The Robinson-Nishikawa method is a variant of the Hoesch reaction, Hoesch synthesis but with low yields. *The Asahina-Tanase method synthesizes some methoxylated xanthones, and xanthones with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichexanthone
Lichexanthone is an organic compound in the structural class of chemicals known as xanthones. Lichexanthone was first isolated and identified by Japanese chemists from a species of leafy lichen in the 1940s. The compound is known to occur in many lichens, and it is important in the taxonomy of species in several genera, such as ''Pertusaria'' and ''Pyxine''. More than a dozen lichen species have a variation of the word lichexanthone incorporated as part of their binomial name. The presence of lichexanthone in lichens causes them to fluoresce a greenish-yellow colour under long-wavelength UV light; this feature is used to help identify some species. Lichexanthone is also found in several plants (many are from the families Annonaceae and Rutaceae), and some species of fungi that do not form lichens. In lichens, the biosynthesis of lichexanthone occurs through a set of enzymatic reactions that start with the molecule acetyl-CoA and sequentially add successive units, forming a longe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthone Synthesis
Xanthone is an organic compound with the molecular formula O 6H4sub>2CO. It is a white solid. In 1939, xanthone was introduced as an insecticide and it currently finds uses as ovicide for codling moth eggs and as a larvicide. Xanthone is also used in the preparation of xanthydrol, which is used in the determination of urea levels in the blood. It can also be used as a photocatalyst. Synthesis Xanthone can be prepared by the heating of phenyl salicylate: Six methods have been reported for synthesizing xanthone derivatives: *The Michael-Kostanecki method uses an equimolar mix of a polyphenol and an ''O''- hydroxybenzoic acid, which are heated with a dehydrating agent. *The Friedel-Crafts method has a benzophenone intermediate. *The Robinson-Nishikawa method is a variant of the Hoesch synthesis but with low yields. *The Asahina-Tanase method synthesizes some methoxylated xanthones, and xanthones with acid-sensitive substituents. *The Tanase method is used to synthesiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthonoid
A xanthonoid is a chemical natural phenolic compound formed from the xanthone backbone. Many members of the Clusiaceae contain xanthonoids. Xanthonoid biosynthesis in cell cultures of ''Hypericum androsaemum'' involves the presence of a benzophenone synthase condensing a molecule of benzoyl-CoA with three malonyl-CoA yielding to 2,4,6-trihydroxybenzophenone. This intermediate is subsequently converted by a benzophenone 3′-hydroxylase, a cytochrome P450 monooxygenase, leading to the formation of 2,3′,4,6-tetrahydroxybenzophenone. Some examples are tomentonone, zeyloxanthonone and calozeyloxanthone isolated from the bark of ''Calophyllum tomentosum'', apetalinone A, B, C and D from '' Calophyllum apetalum'', gaudichaudione A, B, C, D, E, F, G, H, gaudichaudiic acid A, B, C, D, E, morellic acid and forbesione from '' Garcinia gaudichaudii'', methylswertianin and bellidifolin from '' Swertia punicea'' or psorospermin obtained from '' Psorospermum febrifu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mangostin
Mangostin is a natural xanthonoid, a type of organic compound isolated from various parts of the mangosteen tree (''Garcinia mangostana''). It is a yellow crystalline solid with a xanthone core structure. Mangostin and a variety of other xanthonoids from mangosteen have been investigated for biological properties including antioxidant, anti-bacterial, anti-inflammatory, and anticancer activities. In animal studies, mangostin has been found to be a central nervous system depressant which causes sedation, decreased motor activity, and ptosis. The rind of partially ripe mangosteen fruit yields mangostin and also the related compound β-mangostin. Researchers conducted the optimization steps in order to increase the yield of α-Mangostin extraction from the pericarp of the mangosteen and was able to achieve 9.2 g/kg DW. The rind of fully ripe fruits contains the xanthonoids gartanin, 8-disoxygartanin and normangostin. A derivative of mangostin, mangostin-3,6-di-O-glucoside, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthydrol
Xanthydrol is an organic chemical compound. Its formula is C13 H10 O2. Its total molecular weight is 198.221 g/ mol. Xanthydrol is used to test the levels of urea in the bloodstream. Synthesis Xanthydrol can be produced by the reduction of xanthone. See also *Xanthene *Xanthone Xanthone is an organic compound with the molecular formula O 6H4CO. It is a white solid. In 1939, xanthone was introduced as an insecticide and it currently finds uses as Insecticide, ovicide for codling moth eggs and as a larvicide. Xanthone ... References Secondary alcohols Xanthenes {{alcohol-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenyl Salicylate
Phenyl salicylate, or salol, is the organic compound with the formula C6H5O2C6H4OH. It is a white solid. It is occasionally used in sunscreens and as an antiseptic. Production and reactions The title compound was synthesized first in 1883 by the Polish chemist and doctor Marceli Nencki (who didn't publish his findings) and then independently in 1885 by the German chemist Richard Seifert ( de) (1861–1919) (who did publish his findings). It is synthesized by heating salicylic acid with phenol in the presence of phosphoryl chloride. It also arises from heating salicylic acid: :2HOC6H4CO2H → C6H5O2C6H4OH + CO2 + H2O The conversion entails dehydration and decarboxylation. Heating phenyl salicylate in turn gives xanthone. :2C6H5O2C6H4OH → 2C6H5OH + O 6H4sub>2CO + CO2 In this conversion, phenol is produced as well as carbon dioxide. Salol reaction In the salol reaction, phenyl salicylate reacts with ''o''-toluidine in 1,2,4-trichlorobenzene at elevated temperatures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthene
Xanthene (9''H''-xanthene, 10''H''-9-oxaanthracene) is the organic compound with the formula CH2 6H4sub>2O. It is a yellow solid that is soluble in common organic solvents. Xanthene itself is an obscure compound, but many of its derivatives are useful dyes. Xanthene dyes Dyes that contain a xanthene core include fluorescein, eosins, and rhodamines. Xanthene dyes tend to be fluorescent, yellow to pink to bluish red, brilliant dyes. Many xanthene dyes can be prepared by condensation of derivates of phthalic anhydride with derivates of resorcinol or 3-aminophenol. Further reading * See also * Xanthone * Xanthydrol Xanthydrol is an organic chemical compound. Its formula is C13 H10 O2. Its total molecular weight is 198.221 g/ mol. Xanthydrol is used to test the levels of urea in the bloodstream. Synthesis Xanthydrol can be produced by the reduction of xan ... References {{reflist Fungicides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substituent
A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and ''functional group'', as well as ''side chain'' and '' pendant group'', are used almost interchangeably to describe those branches from the parent structure, though certain distinctions are made in polymer chemistry. In polymers, side chains extend from the backbone structure. In proteins, side chains are attached to the alpha carbon atoms of the amino acid backbone.) The suffix ''-yl'' is used when naming organic compounds that contain a single bond replacing one hydrogen; ''-ylidene'' and ''-ylidyne'' are used with double bonds and triple bonds, respectively. In addition, when naming hydrocarbons that contain a substituent, positional numbers are used to indicate which carbon atom the substituent attaches to when such information is needed to distinguish between isomers. Su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ullmann Reaction
The Ullmann reaction or Ullmann coupling is a coupling reaction between aryl halides. Traditionally this reaction is effected by copper, but palladium and nickel are also effective catalysts. The reaction is named after Fritz Ullmann. Mechanism The mechanism of the Ullmann reaction is extensively studied. Complications arise because the reactions are often heterogeneous. With copper as the halide acceptor, organocopper intermediates are invoked. Scope A typical example of classic Ullmann biaryl coupling is the conversion of ''ortho''-chloronitrobenzene into 2,2'-dinitrobiphenyl with a copper - bronze alloy. : : The traditional version of the Ullmann reaction requires harsh reaction conditions, and the reaction has a reputation for erratic yields. Because of these problems many improvements and alternative procedures have been introduced. The classical Ullmann reaction is limited to electron deficient aryl halides and requires harsh reaction conditions. Modern variants of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol
Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 billion kg/year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceutical drugs. Properties Phenol is an organic compound appreciably soluble in water, with about 84.2 g dissolving in 1000 mL (0.895 M). Homogeneous mixtures of phenol and water at phenol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorobenzene
Chlorobenzene is an aromatic organic compound with the chemical formula C6H5Cl. This colorless, flammable liquid is a common solvent and a widely used intermediate in the manufacture of other chemicals. Uses Historical The major use of chlorobenzene is as an intermediate in the production of herbicides, dyestuffs, and rubber. Chlorobenzene is also used as a high-boiling solvent in industrial applications as well as in the laboratory. Chlorobenzene is nitrated on a large scale to give a mixture of 2-nitrochlorobenzene and 4-nitrochlorobenzene, which are separated. These mononitrochlorobenzenes are converted to related 2-nitrophenol, 2-nitroanisole, bis(2-nitrophenyl)disulfide, and 2-nitroaniline by nucleophilic displacement of the chloride, with respectively sodium hydroxide, sodium methoxide, sodium disulfide, and ammonia. The conversions of the 4-nitro derivative are similar. Chlorobenzene once was used in the manufacture of pesticides, most notably DDT, by reaction with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphenylether
Diphenyl ether is the organic compound with the formula ( C6 H5)2 O. It is a colorless solid. This, the simplest diaryl ether, has a variety of niche applications. Synthesis and reactions Diphenyl ether and many of its properties were first reported as early as 1901. It is synthesized by a modification of the Williamson ether synthesis, here the reaction of phenol and bromobenzene in the presence of base and a catalytic amount of copper: :PhONa + PhBr → PhOPh + NaBr Involving similar reactions, diphenyl ether is a significant side product in the high-pressure hydrolysis of chlorobenzene in the production of phenol. Related compounds are prepared by Ullmann reactions. The compound undergoes reactions typical of other phenyl rings, including hydroxylation, nitration, halogenation, sulfonation, and Friedel–Crafts alkylation or acylation. Uses The main application of diphenyl ether is as a eutectic mixture with biphenyl, used as a heat transfer fluid. Such a mix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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