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1-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 several ... [...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] |
Hydroxynaphthoquinone
A hydroxynaphthoquinone (formula: ) is any of several organic compounds that can be viewed as derivatives of a naphthoquinone through replacement of one hydrogen atom (H) by a hydroxyl group (-OH). In general, the term may mean any naphthoquinone derivative where any number ''n'' of hydrogens have been replaced by ''n'' hydroxyls, so that the formula is . In this case the number ''n'' (which is between 1 and 6) is indicated by a multiplier prefix (mono-, di-, tri-, tetra-, penta-, or hexa-). The unqualified term "hydroxynaphthoquinone" usually means a derivative of 1,4-naphthoquinone. Other hydroxy- compounds can be derived from other isomers of the latter, such as 1,2-naphthoquinone and 2,6-naphthoquinone. The IUPAC nomenclature uses dihydronaphthalenedione instead of "naphthoquinone", with the necessary prefixes to indicate the positions of the carbonyl oxygens (=O) — as in 5,8-dihydroxy-1a,8a-dihydronaphthalene-1,4-dione (= 5,8-dihydroxy-1,4-naphthoquinone). The hydroxyn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazonaphthoquinone
Diazonaphthoquinone (DNQ) is a diazo derivative of naphthoquinone. Upon exposure to light, DNQ converts to a derivative that is susceptible to etching. In this way, DNQ has become an important reagent in photoresist technology in the semiconductor industry. Diazonaphthoquinone sulfonic acid esters are components of common photoresist materials. Such photoresists are used in the manufacture of semiconductors. In this application DNQs are mixed with Novolac resin, a type of phenolic polymer. The DNQ functions as a dissolution inhibitor. During the masking/patterning process, portions of the photoresist film are exposed to light while others remain unexposed. In the unexposed regions of the resist film, the DNQ acts as a dissolution inhibitor and the resist remains insoluble in the aqueous base developer. In the exposed regions, the DNQ forms a ketene, which, in turn, reacts with ambient water to form a base soluble indene carboxylic acid. The exposed regions of the photoresist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buparvaquone
Buparvaquone is a naphthoquinone antiprotozoal drug related to atovaquone. It is a promising compound for the therapy and prophylaxis of all forms of theileriosis. Buparvaquone has been shown to have anti-leishmanial activity ''in vitro''. It can be used to treat bovine East Coast fever protozoa ''in vitro'', along with the only other substance known – ''Peganum harmala''. It is the only really effective commercial therapeutic product against bovine theileriosis, where it has been used since the late 1980s. Industrial production It was first produced in Great Britain, then in Germany. Its patent expired in the mid-2000s, and was then produced in different countries, e.g., India and Iran. Use in bovine theileriosis Using a single dose of 2,5 mg/kg, the recovery rate of curable cases is 90 to 98%. In tropical theileriosis, a dosage of 2.0 mg/kg has the same efficacy. Body temperature returns to normal in two to five days. Parasitemia lowers from 12% on day 0 to 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atovaquone
Atovaquone, sold under the brand name Mepron, is an antimicrobial medication for the prevention and treatment of ''Pneumocystis jirovecii'' pneumonia (PCP). Atovaquone is a chemical compound that belongs to the class of naphthoquinones. Atovaquone is a hydroxy-1,4-naphthoquinone, an analog of both ubiquinone and lawsone, with antipneumocystic activity. Medical uses Atovaquone is a medication used to treat or prevent: * For pneumocystis pneumonia (PCP), it is used in mild cases, although it is not approved for treatment of severe cases. * For toxoplasmosis, the medication has antiparasitic and therapeutic effects. * For malaria, it is one of the two components (along with proguanil) in the drug Malarone. Malarone has fewer side effects and is more expensive than mefloquine. Resistance has been observed. * For babesia, it is often used in conjunction with oral azithromycin. Trimethoprim/sulfamethoxazole (TMP-SMX, Bactrim) is generally considered first-line therapy for PCP (not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydroxynaphthoquinone
A dihydroxynaphthoquinone (formula: ) is any of several organic compounds that can be viewed as derivatives of naphthoquinone through replacement of two hydrogen atoms (H) by hydroxyl groups (OH). The unqualified term "dihydroxynaphthoquinone" usually means a derivative of 1,4-naphthoquinone. Other dihydroxy- compounds can be derived from the two other known isomers, 1,2-naphthoquinone (''ortho''-) and 2,6-naphthoquinone (''amphi''-). Isomers From 1,4-naphthoquinone Due to the symmetry of the parent quinone, there are only nine distinct isomers of dihydroxy-1,4-naphthoquinone: * 2,3-Dihydroxy-1,4-naphthoquinone. * 2,5-Dihydroxy-1,4-naphthoquinone. * 2,6-Dihydroxy-1,4-naphthoquinone. * 2,7-Dihydroxy-1,4-naphthoquinone. * 2,8-Dihydroxy-1,4-naphthoquinone. * 5,6-Dihydroxy-1,4-naphthoquinone. * 5,7-Dihydroxy-1,4-naphthoquinone. *5,8-Dihydroxy-1,4-naphthoquinone (naphthazarin). J. Khalafy and J.M. Bruce (2002), ''Oxidative dehydrogenation of 1-tetralones: Synthesis of juglone, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5,8-Dihydroxy-1,4-naphthoquinone
Naphthazarin, often called 5,8-dihydroxy-1,4-naphthoquinone or 5,8-dihydroxy-1,4-naphthalenedione (IUPAC), is a naturally occurringThomson R.H. Naturally Occurring Quinones. Academic Press, London (1971). Quoted by Khalafy and Bruce.Thomson R.H. Naturally Occurring Quinones III. Chapman and Hall, London (1987). Quoted by Khalafy and Bruce. organic compound with formula , formally derived from 1,4-naphthoquinone through replacement of two hydrogen atoms by hydroxyl (OH) groups. It is thus one of many dihydroxynaphthoquinone structural isomers. Naphthazarin is soluble in 1,4-dioxane from which it crystallizes as deep red needles that melt at 228−232 °C. Synthesis Naphtharazin can be prepared by condensation of 1,4-dimethoxybenzene with 2,3-dichloromaleic anhydride followed by reductive dechlorination and reoxidation.Lewis J.R. and Paul J.J.(1977). Z. Naturforsch., B, 32: 1473. Quoted by Khalafy and Bruce.Huot R. and Brassard P. (1974). Can. J. Chem., 52: 838. Quot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Menadione
Menadione is a natural organic compound with the formula C6H4(CO)2C2H(CH3). It is an analog of 1,4-naphthoquinone with a methyl group in the 2-position. It is sometimes called vitamin K3. Use is allowed as a nutritional supplement in animal feed because of its vitamin K activity. Biochemistry Menadione is converted to vitamin K2 (specifically, MK-4) by the prenyltransferase action of vertebrate UBIAD1. This reaction requires the hydroquinone (reduced) form of K3, menadiol, produced by an unidentified enzyme. Menadione is also a circulating form of vitamin K, produced in small amounts (1–5%) after intestinal absorption of K1 and K2. This circulation explains the uneven tissue distribution of MK-4, especially since menadione can penetrate the blood–brain barrier. The cleavage enzyme is yet to be identified. Terminology The compound is variously known as vitamin K3 and provitamin K3. Proponents of the latter name generally argue that the compound is not a real vitamin d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin K
Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulation (K from ''Koagulation'', German for "coagulation") or for controlling binding of calcium in bones and other tissues. The complete synthesis involves final modification of these so-called "Gla proteins" by the enzyme gamma-glutamyl carboxylase that uses vitamin K as a cofactor. Vitamin K is used in the liver as the intermediate VKH2 to deprotonate a glutamate residue and then is reprocessed into vitamin K through a vitamin K oxide intermediate. The presence of uncarboxylated proteins indicates a vitamin K deficiency. Carboxylation allows them to bind ( chelate) calcium ions, which they cannot do otherwise. Without vitamin K, blood coagulation is seriously impaired, and uncontrolled bleeding occurs. Research suggests that deficien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 (196 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plumbagin
Plumbagin or 5-hydroxy-2-methyl-1,4-naphthoquinone is an organic compound with the chemical formula . It is regarded as a toxin and it is genotoxic and mutagenic. Plumbagin is a yellow dye,Black Walnut Drugs.com. formally derived from naphthoquinone. It is named after the plant genus '' Plumbago'', from which it was originally isolated. It is also commonly found in the genera '' Drosera'' and '' |
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