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Phloroglucinol
Phloroglucinol is an organic compound with the formula C6H3(OH)3. It is a colorless solid. It is used in the synthesis of pharmaceuticals and explosives. Phloroglucinol is one of three isomeric benzenetriols. The other two isomers are hydroxyquinol (1,2,4-benzenetriol) and pyrogallol (1,2,3-benzenetriol). Phloroglucinol, and its benzenetriol isomers, are still defined as "phenols" according to the IUPAC official nomenclature rules of chemical compounds. Many such monophenolics are often termed "polyphenols" by the cosmetic and parapharmaceutical industries, which does not match the scientifically accepted definition. Synthesis and occurrence In 1855, phloroglucinol was first prepared from phloretin by the Austrian chemist Heinrich Hlasiwetz (1825–1875). A modern synthesis of involves hydrolysis of benzene-1,3,5-triamine and its derivatives. Representative is the following route from trinitrobenzene. : The synthesis is noteworthy because ordinary aniline derivatives are un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloroglucinol UV Visible Spectrum
Phloroglucinol is an organic compound with the formula C6H3(OH)3. It is a colorless solid. It is used in the synthesis of pharmaceuticals and explosives. Phloroglucinol is one of three isomeric benzenetriols. The other two isomers are hydroxyquinol (1,2,4-benzenetriol) and pyrogallol (1,2,3-benzenetriol). Phloroglucinol, and its benzenetriol isomers, are still defined as "phenols" according to the IUPAC official nomenclature rules of chemical compounds. Many such monophenolics are often termed "polyphenols" by the cosmetic and parapharmaceutical industries, which does not match the scientifically accepted definition. Synthesis and occurrence In 1855, phloroglucinol was first prepared from phloretin by the Austrian chemist Heinrich Hlasiwetz (1825–1875). A modern synthesis of involves hydrolysis of benzene-1,3,5-triamine and its derivatives. Representative is the following route from trinitrobenzene. : The synthesis is noteworthy because ordinary aniline derivatives are unre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoesch Reaction
The Hoesch reaction or Houben–Hoesch reaction is an organic reaction in which a nitrile reacts with an arene compound to form an aryl ketone. The reaction is a type of Friedel-Crafts acylation with hydrogen chloride and a Lewis acid catalyst. The synthesis of 2,4,6-Trihydroxyacetophenone (THAP) from phloroglucinol is representative: If two-equivalents are added, 2,4-Diacetylphloroglucinol is the product. : An imine can be isolated as an intermediate reaction product. The attacking electrophile is possibly a species of the type R-C+=NHCl−. The arene must be electron-rich i.e. phenol or aniline type. A related reaction is the Gattermann reaction in which hydrocyanic acid not a nitrile is used. The reaction is named after Kurt Hoesch and Josef Houben''Über die Kern-Kondensation von Phenolen und Phenol-äthern mit Nitrilen zu Phenol- und Phenol-äther-Ketimiden und -Ketonen (I.)'' Berichte der deutschen chemischen Gesellschaft (A and B Series) Volume 59, Issue 11, Date: 8. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Phenol
In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. As they are present in food consumed in human diets and in plants used in traditional medicine of several cultures, their role in human health and disease is a subject of research. Some phenols are germicidal and are used in formulating disinfectants. Classification Various classification schemes can be applied. A commonly used scheme is based on the number of carbons and was devised by Jeffrey Harborne and Simmonds in 1964 and published in 1980: C6-C7-C6 Diarylheptanoids are not included in this Harborne classification. They can also be classified on the basis of their number of phenol groups. They can therefore be called ''simple phenols'' or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentacarbon Dioxide
Pentacarbon dioxide, officially penta-1,2,3,4-tetraene-1,5-dione, is an oxide of carbon (an oxocarbon) with formula C5O2 or O=C=C=C=C=C=O. The compound was described in 1988 by Günter Maier and others, who obtained it by pyrolysis of cyclohexane-1,3,5-trione (phloroglucin, the tautomeric form of phloroglucinol). It has also been obtained by flash vapor pyrolysis of 2,4,6-tris(diazo)cyclohexane-1,3,5-trione (C6N6O3). It is stable at room temperature in solution. The pure compound is stable up to −96 °C, at which point it polymerizes. References See also * Ethylene dione (C2O2) * Carbon suboxide Carbon suboxide, or tricarbon dioxide, is an organic, oxygen-containing chemical compound with formula and structure . Its four cumulative double bonds make it a cumulene. It is one of the stable members of the series of linear oxocarbons , whi ... (C3O2) {{Oxides of carbon Oxocarbons Heterocumulenes Enones Ketenes Diketones Substances discovered in the 1980s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heinrich Hlasiwetz
Heinrich Hlasiwetz (7 April 1825 – 7 October 1875) was an Austrian chemist born in Reichenberg, Bohemia. Son of a pharmacist, he studied at the University of Jena, where his instructors included Johann Wolfgang Döbereiner (1780-1849), Heinrich Wilhelm Ferdinand Wackenroder (1798-1854) and Matthias Jakob Schleiden (1804-1881). Later he studied under Josef Redtenbacher (1810–1870) in Prague. In 1848 he earned the diploma of ''Magister Pharmacia'', and during the following year received his doctorate in chemistry. In 1849 he began work as an assistant to Friedrich Rochleder (1819-1874), later becoming an associate professor of chemistry at the University of Innsbruck (1854). In 1867 he became a professor at the Vienna University of Technology, where from 1869 he represented general and analytical chemistry. During his career he largely worked with resins, tannins and protein compounds. Hlasiwetz is remembered for his chemical analysis of quercitrin, phloroglucinol, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 practi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloretin
Phloretin is a dihydrochalcone, a type of natural phenol. It can be found in apple tree leaves and the Manchurian apricot. Metabolism In rats, ingested phlorizin is converted into phloretin by hydrolytic enzymes in the small intestine. Phloretin hydrolase hydrolyses phloretin into phloretic acid and phloroglucinol. Pharmacological research In an animal model, phloretin inhibited active transport of glucose into cells by SGLT1 and SGLT2, though the inhibition is weaker than by its glycoside phlorizin. An important effect of this is the inhibition of glucose absorption by the small intestine and the inhibition of renal glucose reabsorption. Phloretin also inhibits a variety of urea transporters. It induces urea loss and diuresis when coupled with high protein diets. Phloretin has been found to inhibit weight gain and improve metabolic homeostasis in mice fed with high-fat diet. Phloretin inhibits aquaporin 9 (AQP9) on mouse hepatocytes. Nanoparticle Synthesis Phlor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzenetriol
The trihydroxybenzenes (or benzenetriols) are organic compounds with the formula C6H3(OH)3. Also classified as polyphenols, they feature three hydroxyl groups substituted onto a benzene ring. They are white solids with modest solubility in water. : The enzyme pyrogallol hydroxytransferase uses benzene-1,2,3,5-tetrol and benzene-1,2,3-triol (pyrogallol), whereas its two products are benzene-1,3,5-triol (phloroglucinol) and benzene-1,2,3,5-tetrol. This enzyme can be found in ''Pelobacter acidigallici.'' See also * Dihydroxybenzenes * Tetrahydroxybenzenes * Pentahydroxybenzene * Hexahydroxybenzene Benzenehexol, also called hexahydroxybenzene, is an organic compound with formula or . It is a six-fold Phenols, phenol of benzene. The product is also called hexaphenol, but this name has been used also for other substances. Benzenehexol is a c ... References {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphenol
Polyphenols () are a large family of naturally occurring organic compounds characterized by multiples of phenol units. They are abundant in plants and structurally diverse. Polyphenols include flavonoids, tannic acid, and ellagitannin, some of which have been used historically as dyes and for tanning garments. Etymology The name derives from the Ancient Greek word (''polus'', meaning "many, much") and the word phenol which refers to a chemical structure formed by attaching to an aromatic benzenoid ( phenyl) ring to a hydroxyl (-OH) group as is found in alcohols (hence the ''-ol'' suffix). The term polyphenol has been in use at least since 1894. Definition The term polyphenol is not well-defined, but is generally agreed that they are natural products "having a polyphenol structure (i.e., several hydroxyl groups on aromatic rings)" including four principal classes: "phenolic acids, flavonoids, stilbenes, and lignans". *Flavonoids include flavones, flavonols, flavan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enol
In organic chemistry, alkenols (shortened to enols) are a type of reactive structure or intermediate in organic chemistry that is represented as an alkene ( olefin) with a hydroxyl group attached to one end of the alkene double bond (). The terms ''enol'' and ''alkenol'' are portmanteaus deriving from "-ene"/"alkene" and the "-ol" suffix indicating the hydroxyl group of alcohols, dropping the terminal "-e" of the first term. Generation of enols often involves removal of a hydrogen adjacent (α-) to the carbonyl group—i.e., deprotonation, its removal as a proton, . When this proton is not returned at the end of the stepwise process, the result is an anion termed an enolate (see images at right). The enolate structures shown are schematic; a more modern representation considers the molecular orbitals that are formed and occupied by electrons in the enolate. Similarly, generation of the enol often is accompanied by "trapping" or masking of the hydroxy group as an ethe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
Tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure ( valence bond theory) depictions of a single chemical species, whose true structure is best described as the "average" of the idealized, hyp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It has been used as a recreational drug to cause intoxication. Production Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Ethanol is mixed with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
