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4-pyrone
4-Pyrone (γ-pyrone or pyran-4-one) is an unsaturated cyclic chemical compound with the molecular formula C5H4O2. It is isomeric with 2-pyrone. Preparation 4-Pyrone is prepared via the thermal decarboxylation of chelidonic acid. Reactions 4-Pyrone and its derivatives react with amines in protic solvents to form 4-Pyridones. Derivatives 4-Pyrone forms the central core of several natural chemical compounds, including maltol, meconic acid, kojic acid, and of the important class of the Flavones. : See also * Pyrone * 4-Pyridone * Dehydroacetic acid Dehydroacetic acid is an organic compound which has several industrial applications. The compound is classified as a pyrone derivative. It presents as an odorless, colorless to white crystalline powder, almost insoluble in water and moderately so ... References {{DEFAULTSORT:Pyrone, 4- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrone
Pyrones or pyranones are a class of heterocyclic chemical compounds. They contain an unsaturated six-membered ring containing one oxygen atom and a ketone functional group. There are two isomers denoted as 2-pyrone and 4-pyrone. The 2-pyrone (or α-pyrone) structure is found in nature as part of the coumarin ring system. 4-Pyrone (or γ-pyrone) is found in some natural chemical compounds such as chromone, maltol and kojic acid. See also * Furanone 2-Furanone is a heterocyclic organic compound. It is also known as γ-crotonolactone (GCL), as it is formally the lactone derived from γ-hydroxyisocrotonic acid. The chemical is colloquially called "butenolide", and is the parent structure for th ..., which has one fewer carbon atom in the ring. References {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelidonic Acid
Chelidonic acid is a heterocyclic organic acid with a pyran skeleton. Preparation Chelidonic acid can be prepared in two steps from diethyl oxalate and acetone: : Uses Chelidonic acid is used to synthesize 4-pyrone via thermal decarboxylation. Natural occurrence Chelidonic acid was first discovered in extracts of ''Chelidonium majus''. It occurs naturally in plants of the Asparagales order. Potassium chelidonate has been found to be responsible for nyctinasty in some plants; specifically, it has been found to regulate the closing of leaves of ''Cassia mimosoides'' at nightfall. See also * Dimethyl oxalate * Dehydroacetic acid Dehydroacetic acid is an organic compound which has several industrial applications. The compound is classified as a pyrone derivative. It presents as an odorless, colorless to white crystalline powder, almost insoluble in water and moderately so ... References {{reflist 4-Pyrones Dicarboxylic acids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kojic Acid
Kojic acid is a chelation agent produced by several species of fungi, especially ''Aspergillus oryzae'', which has the Japanese common name ''koji''. Kojic acid is a by-product in the fermentation process of malting rice, for use in the manufacturing of sake, the Japanese rice wine. It is a mild inhibitor of the formation of pigment in plant and animal tissues, and is used in food and cosmetics to preserve or change colors of substances. It forms a bright red complex with ferric ions. Biosynthesis 13C-Labeling studies have revealed at least two pathways to kojic acid. In the usual route, dehydratase enzymes convert glucose to kojic acid. Pentoses are also viable precursors in which case dihydroxyacetone is invoked as an intermediate. Applications Kojic acid may be used on cut fruits to prevent oxidative browning, in seafood to preserve pink and red colors, and in cosmetics to lighten skin. As an example of the latter, it is used to treat skin diseases like melasma. Kojic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigma-Aldrich
Sigma-Aldrich (formally MilliporeSigma) is an American chemical, life science, and biotechnology company that is owned by the German chemical conglomerate Merck Group. Sigma-Aldrich was created in 1975 by the merger of Sigma Chemical Company and Aldrich Chemical Company. It grew through various acquisitions until it had over 9,600 employees and was listed on the Fortune 1000. The company is headquartered in St. Louis and has operations in approximately 40 countries. In 2015, the German chemical conglomerate Merck Group acquired Sigma-Aldrich for $17 billion. The company is currently a part of Merck's life science business and in combination with Merck's earlier acquired Millipore Corporation, Millipore, operates as MilliporeSigma. History Sigma Chemical Company of St. Louis and Aldrich Chemical Company of Milwaukee were both American specialty chemical companies when they merged in August 1975. The company grew throughout the 1980s and 1990s, with significant expansion in fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maltol
Maltol is a naturally occurring organic compound that is used primarily as a flavor enhancer. It is found in the bark of larch tree, in pine needles, and in roasted malt (from which it gets its name). It is a white crystalline powder that is soluble in hot water, chloroform, and other polar solvents. Because it has the odor of cotton candy and caramel, maltol is used to impart a sweet aroma to fragrances. Maltol's sweetness adds to the odor of freshly baked bread, and is used as a flavor enhancer (INS number 636) in breads and cakes. Maltol, like related 3-hydroxy-4-pyrones such as kojic acid, binds to hard metal centers such as Fe3+, Ga3+, Al3+, and VO2+. Related to this property, maltol has been reported to greatly increase aluminum uptake in the body and to increase the oral bioavailability of gallium and iron.{{cite journal , author1=D.M. Reffitt , author2=T.J. Burden , author3=P.T. Seed , author4=J. Wood J , author5=R.P. Thompson , author6=J.J. Powell , title = Assessme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maltol
Maltol is a naturally occurring organic compound that is used primarily as a flavor enhancer. It is found in the bark of larch tree, in pine needles, and in roasted malt (from which it gets its name). It is a white crystalline powder that is soluble in hot water, chloroform, and other polar solvents. Because it has the odor of cotton candy and caramel, maltol is used to impart a sweet aroma to fragrances. Maltol's sweetness adds to the odor of freshly baked bread, and is used as a flavor enhancer (INS number 636) in breads and cakes. Maltol, like related 3-hydroxy-4-pyrones such as kojic acid, binds to hard metal centers such as Fe3+, Ga3+, Al3+, and VO2+. Related to this property, maltol has been reported to greatly increase aluminum uptake in the body and to increase the oral bioavailability of gallium and iron.{{cite journal , author1=D.M. Reffitt , author2=T.J. Burden , author3=P.T. Seed , author4=J. Wood J , author5=R.P. Thompson , author6=J.J. Powell , title = Assessme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavones
Flavones (from Latin ''flavus'' "yellow") are a class of flavonoids based on the backbone of 2-phenylchromen-4-one (2-phenyl-1-benzopyran-4-one) (as shown in the first image of this article). Flavones are common in foods, mainly from spices, and some yellow or orange fruits and vegetables. Common flavones include apigenin (4',5,7-trihydroxyflavone), luteolin (3',4',5,7-tetrahydroxyflavone), tangeritin (4',5,6,7,8-pentamethoxyflavone), chrysin (5,7-dihydroxyflavone), and 6-hydroxyflavone. Intake and elimination The estimated daily intake of flavones is about 2 mg per day. Following ingestion and metabolism, flavones, other polyphenols, and their metabolites are absorbed poorly in body organs and are rapidly excreted in the urine, indicating mechanisms influencing their presumed absence of metabolic roles in the body. Drug interactions Flavones have effects on CYP (P450) activity, which are enzymes that metabolize most drugs in the body. Biosynthesis The biosynthesis of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meconic Acid
Meconic acid, also known as acidum meconicum and poppy acid, is a chemical substance found in certain plants of the poppy family, Papaveraceae, such as ''Papaver somniferum'' (opium poppy) and ''Papaver bracteatum''. Meconic acid constitutes about 5% of opium and can be used as an analytical marker for the presence of opium. Meconic acid has erroneously been described as a mild narcotic, but it has little or no physiological activity, and is not used medicinally. Meconic acid forms salts with alkaloids and metals. These salts as well as meconic acid esters are called meconates. Meconic acid was first isolated by Friedrich Sertürner in 1805.Friedrich Sertürner (1805(Untitled letter to the editor) ''Journal der Pharmacie für Aerzte, Apotheker und Chemisten'' (Journal of Pharmacy for Physicians, Apothecaries, and Chemists), 13 : 229–243. See also: Sertuerner (1817"Ueber das Morphium, eine neue salzfähige Grundlage, und die Mekonsäure, als Hauptbestandtheile des Opiums"(On m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4-Pyridone
4-Pyridone is an organic compound with the formula . It is a colorless solid. The compound exists in equilibrium with a minor tautomer, pyridin-4-ol. Preparation 4-Pyridone, and its Derivative (chemistry), derivatives, are prepared from 4-Pyrone and amines in protic solvents. See also * 4-Piperidone * Dehydroacetic acid References 4-Pyridones, {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturated And Unsaturated Compounds
In chemistry, a saturated compound is a chemical compound (or ion) that resists the addition reactions, such as hydrogenation, oxidative addition, and binding of a Lewis acids and bases, Lewis base. The term is used in many contexts and for many classes of chemical compounds. Overall, saturated compounds are less reactive than unsaturated compounds. Saturation is derived from the Latin word ''saturare'', meaning 'to fill'. Organic chemistry Unsaturated compounds generally carry out typical addition reactions that are not possible with saturated compounds such as alkanes. A saturated organic compound has only single bonds between carbon atoms. An important class of saturated compounds are the alkanes. Many saturated compounds have functional groups, e.g., alcohols. Unsaturated organic compounds The concept of saturation can be described using various naming systems, formulas, and Analytical chemistry, analytical tests. For instance, IUPAC nomenclature of organic chemistry, IU ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protic Solvent
In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group ), a nitrogen (as in an amine group or ), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a Labile#Chemistry, labile is called a protic solvent. The molecules of such solvents readily donate protons () to solutes, often via hydrogen bonding. Water is the most common protic solvent. Conversely, polar aprotic solvents cannot donate protons but still have the ability to dissolve many salts. Methods for purification of common solvents are available See also * Autoprotolysis References {{Chemical solutions Solvents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
