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2,3,5,7-Tetrahydroxy-1,4-naphthalenedione
2,3,5,7-Tetraahydroxy-1,4-naphthalenedione, also called 2,3,5,7-tetrahydroxynaphthoquinone or spinochrome B, is an organic compound with formula , formally derived from 1,4-naphthoquinone through the replacement of four hydrogen atoms by hydroxyl (OH) groups. Spinochrome B occurs naturally as pigment in the shell and spines of sea urchins such as the Japanese dull red species ''aka-uni'' ('' Pseudocentrotus depressus''), the greenish-black ''murasaki-uni'' ('' Heliocidaris crassispina''), and the brown ''bafun-uni'' ('' Strongylocentrotus pulcherrimus''). Chika KURODA and Masae OKAJIMA (1958), ''Studies on the Derivatives of Naphthoquinones, XIV. The pigments of sea urchins, IX''. Proc. Japan Acad., volume 34, pages 616--618Online versionaccessed on 2010-02-01. Pigment M2 is drawn as 2,3,6,8-thNQ but that is the same as 2,3,5,7-thNQ. The genus ''Heliocedaris'' should be ''Heliocidaris'' and the species ''purcherrmus'' should be ''pulcherrimus''. Chika KURODA and Masae OKAJIMA (1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphthoquinone
Naphthoquinones constitute a class of organic compounds structurally related to naphthalene. Two isomers are common for the parent naphthoquinones: * 1,2-Naphthoquinone * 1,4-Naphthoquinone Natural products * Alkannin * Hexahydroxy-1,4-naphthalenedione * Juglone * Lapachol * Lawsone * Menatetrenone * 2-Methoxy-1,4-naphthoquinone, a compound found in ''Impatiens'' species * Nigrosporin B * 2,3,5,6,8-Pentahydroxy-1,4-naphthalenedione * Phylloquinone * Plumbagin * 2,3,5,7-Tetrahydroxy-1,4-naphthalenedione * Vitamin K and related compounds Synthetic naphthoquinones * Menadione (2-Methyl-1,4-naphthoquinone), a vitamin K mimic * 5,8-Dihydroxy-1,4-naphthoquinone and dihydroxynaphthoquinones * Atovaquone * Buparvaquone, an antiprotozoal drug used in veterinary medicine * Diazonaphthoquinone, a diazo derivative of naphthoquinone * 1,2-Naphthoquinone, from the biodegradation of naphthalene. See also * Hydroxynaphthoquinone A hydroxynaphthoquinone (formula: ) is any of sever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. 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, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resorcinols
Resorcinol (or resorcin) is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or ''meta''-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide. Production Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol. Resorcinol is an expensive chemical, produced in only a very few locations around the world (to date only four commercial plants are known to be operative: in the United States, Germany,China and Japan), and as such it is the determining factor in the cost of PRF adhesives. Many additional routes exist for resorcinol. It was formerly produced by disulfonation of benzene followed by hydrolysis of the 1,3-disulfonate. This method has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechols
Catechol ( or ), also known as pyrocatechol or 1,2-dihydroxybenzene, is a toxic organic compound with the molecular formula . It is the ''ortho'' isomer of the three isomeric benzenediols. This colorless compound occurs naturally in trace amounts. It was first discovered by destructive distillation of the plant extract catechin. About 20,000 tonnes of catechol are now synthetically produced annually as a commodity organic chemical, mainly as a precursor to pesticides, flavors, and fragrances. Catechol occurs as feathery white crystals that are very rapidly soluble in water. Isolation and synthesis Catechol was first isolated in 1839 by Edgar Hugo Emil Reinsch (1809–1884) by distilling it from the solid tannic preparation catechin, which is the residuum of catechu, the boiled or concentrated juice of ''Mimosa catechu'' (''Acacia catechu''). Upon heating catechin above its decomposition point, a substance that Reinsch first named ''Brenz-Katechusäure'' (burned catechu acid) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,3,5,6,8-Pentahydroxy-1,4-naphthalenedione
2,3,5,6,8-Pentahydroxy-1,4-naphthalenedione, also called 2,3,5,6,8-pentahydroxy-1,4-naphthoquinone or spinochrome D, is an organic compound with formula , formally derived from 1,4-naphthoquinone through the replacement of five hydrogen atoms by hydroxyl (OH) groups. Spinochrome D occurs naturally as a brownish red pigment in the shell and spines of sea urchins such as the Japanese ''aka-uni'' ('' Pseudocentrotus depressus''). Chika KURODA and Masae OKAJIMA (1967), ''Studies on the Derivatives of Naphthoquinones, XVIII. The pigments of sea urchins, XIII''. Proc. Japan Acad., volume 43, pages 41--44Online versionaccessed on 2010-02-01. It is soluble in diethyl ether and crystallizes as brownish red needles that sublime at 285−295 °C. The compound gives a yellowish brown solution when treated with sodium hydroxide, a bluish green solution with ferric chloride, and a violet precipitate with lead acetate. It forms a five-fold acetate ester, ()5, that crystallizes from meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,3,5,6,7,8-Hexahydroxy-1,4-naphthalenedione
Spinochrome E, 2,3,5,6,7,8-Hexahydroxy-1,4-naphthalenedione, also called hexahydroxynaphthoquinone is a polyhydroxylated 1,4-naphthoquinones, pigments found in sea urchin shell ("test"), spine, gonads, coelomic fluid, and eggs, of sea urchin commonly known as spinochromes. These natural phenolic compounds are quinones that are known to have pharmacological properties. The several hydroxyl groups are appropriate for free-radical scavenging, which diminishes ROS and prevents redox imbalance. Mechanisms are described such as scavenging of reactive oxygen species (ROS), interaction with lipid peroxide radicals, chelation of metal ions, inhibition of lipid peroxidation and regulation of the cell redox potential. Spinochrome E formula shows that have one extra hydroxyl group that Echinochrome A and it is formally derived from naphthoquinone (1,4-naphtalenedione) through replacement of all six hydrogen atoms by hydroxyl (OH) groups. The numerical prefixes "2,3,5,6,7,8" are supe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetate
An acetate is a salt (chemistry), salt formed by the combination of acetic acid with a base (e.g. Alkali metal, alkaline, Alkaline earth metal, earthy, Transition metal, metallic, nonmetallic or radical Radical (chemistry), base). "Acetate" also describes the conjugate acid, conjugate base or ion (specifically, the negatively charged ion called an anion) typically found in aqueous solution and written with the chemical formula . The neutral molecules formed by the combination of the acetate ion and a ''positive'' ion (called a cation) are also commonly called "acetates" (hence, ''acetate of lead'', ''acetate of aluminum'', etc.). The simplest of these is hydrogen acetate (called acetic acid) with corresponding salts, esters, and the polyatomic ion, polyatomic anion , or . Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In nature, acetate is the most common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead Acetate
Lead acetate can refer to: * Lead subacetate (Basic lead acetate), Pb3(OH)4(CH3COO)2 * Lead(IV) acetate (plumbic acetate), Pb(CH3COO)4 * Lead(II) acetate Lead(II) acetate (Pb(CH3COO)2), also known as lead acetate, lead diacetate, plumbous acetate, sugar of lead, lead sugar, salt of Saturn, or Goulard's powder, is a white crystalline chemical compound with a slightly sweet taste. Like many other l ... (lead diacetate), Pb(CH3COO)2 and the trihydrate Pb(CH3COO)2.3H2O {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and deterge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
