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Alpha-Ketoisovaleric Acid
α-Ketoisovaleric acid is an organic compound with the formula (CH3)2CHC(O)CO2H. It is a ketoacid. With a melting point just above room temperature, it is usually an oil or semi-solid. The compound is colorless. It is a metabolite of valine and a precursor to pantothenic acid, a prosthetic group found in several cofactors. In the biological context, is usually encountered as its conjugate base ketoisovalerate, (CH3)2CHC(O)CO2−. Synthesis and reactions α-Ketoisovalerate undergoes hydroxymethylation to give ketopantoate: :(CH3)2CHC(O)CO2− + CH2O → HOCH2(CH3)2CC(O)CO2− This conversion is catalyzed by ketopantoate hydroxymethyltransferase. Like many α-ketoacids, α-ketoisovaleric acid is prone to decarboxylation to give isobutyraldehyde: :(CH3)2CHC(O)CO2H → (CH3)2CHCHO + CO2 Genetic engineering has been used to produce the biofuel isobutanol Isobutanol (IUPAC nomenclature: 2-methylpropan-1-ol) is an organic compound with the formula (CH3)2CHCH2OH (sometimes r ... [...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] |
Ketoacid
In organic chemistry, keto acids or ketoacids (also called oxo acids or oxoacids) are organic compounds that contain a carboxylic acid group () and a ketone group ().Franz Dietrich Klingler, Wolfgang Ebertz "Oxocarboxylic Acids" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. In several cases, the keto group is hydrated. The alpha-keto acids are especially important in biology as they are involved in the Krebs citric acid cycle and in glycolysis. Common types of keto acids include: *Alpha-keto acids, alpha-ketoacids, or 2-oxoacids have the keto group adjacent to the carboxylic acid. They often arise by oxidative deamination of amino acids, and reciprocally, they are precursors to the same. Alpha-keto acids possesses extensive chemistry as acylation agents. Furthermore, alpha-keto acids such as phenylpyruvic acid are endogenous sources for carbon monoxide (as a gasotransmitter) and pharmaceutical prodrug scaffold. Important representatives: ** p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valine
Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH3+ form under biological conditions), an α- carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain isopropyl group, making it a non-polar aliphatic amino acid. It is essential in humans, meaning the body cannot synthesize it: it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, beans and legumes. It is encoded by all codons starting with GU (GUU, GUC, GUA, and GUG). History and etymology Valine was first isolated from casein in 1901 by Hermann Emil Fischer. The name valine comes from valeric acid, which in turn is named after the plant valerian due to the presence of the acid in the roots of the plant. Nomenclature According to IUPAC, carbon atoms forming valine are numbered sequentially s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pantothenic Acid
Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to, in general, synthesize and metabolize proteins, carbohydrates, and fats. Pantothenic acid is the combination of pantoic acid and β-alanine. Its name derives from the Greek ''pantos'', meaning "from everywhere", as minimally, at least small quantities of pantothenic acid are found in nearly every food. Human deficiency is very rare. As a dietary supplement or animal feed ingredient, the form commonly used is calcium pantothenate because of chemical stability, and hence long product shelf life, compared to sodium pantothenate or free pantothenic acid. Definition Pantothenic acid is a water-soluble vitamin, one of the B vitamins. It is synthesized from the amino acid β-alanine and pantoic acid (see biosynthesis and structure of coenzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxymethylation
Hydroxymethylation is a chemical reaction that installs the CH2OH group. The transformation can be implemented in many ways and applies to both industrial and biochemical processes. Hydroxymethylation with formaldehyde A common method for hydroxymethylation involves the reaction of formaldehyde with active C-H and N-H bonds: :R3C-H + CH2O → R3C-CH2OH :R2N-H + CH2O → R2N-CH2OH A typical active C-H bond is provided by a terminal acetylene or the alpha protons of an aldehyde. In industry, hydroxymethylation of acetaldehyde with formaldehyde is used in the production of pentaerythritol: P-H bonds are also prone to reaction with formaldehyde. Tetrakis(hydroxymethyl)phosphonium chloride ( (CH2OH)4l) is produced in this way from phosphine (PH3). Hydroxymethylation in demethylation 5-Methylcytosine is a common epigenetic marker. The methyl group is modified by oxidation of the methyl group in a process called hydroxymethylation: :RCH3 + O → RCH2OH This oxidation is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketopantoate
Ketopantoic acid is the organic compound with the formula HOCH2(CH3)2CC(O)CO2H. At physiological conditions, ketopantoic acid exists as its conjugate base, ketopantoate (HOCH2(CH3)2CC(O)CO2−). Biosynthetic context Its biosynthesis proceeds from ketoisovalerate by hydroxymethylation: :(CH3)2CHC(O)CO2− + CH2O → HOCH2(CH3)2CC(O)CO2− This conversion is catalyzed by ketopantoate hydroxymethyltransferase, which gives ketopantoate. Ketopantoate is substrate for 2-dehydropantoate 2-reductase, which produces pantoate, a precursor to pantothenic acid Pantothenic acid, also called vitamin B5 is a water-soluble B vitamin and therefore an essential nutrient. All animals require pantothenic acid in order to synthesize coenzyme A (CoA) – essential for fatty acid metabolism – as well as to, i ..., a common prosthetic group.{{cite book , doi=10.1016/S0083-6729(01)61005-7, chapter=The Biosynthesis of Coenzyme a in Bacteria, title=Cofactor Biosynthesis, series=Vitamins & Hormo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isobutyraldehyde
Isobutyraldehyde is the chemical compound with the formula (CH3)2CHCHO. It is an aldehyde, isomeric with n-butyraldehyde (butanal). Isobutyraldehyde is made, often as a side-product, by the hydroformylation of propene. Its odour is described as that of wet cereal or straw. It undergoes the Cannizaro reaction even though it has alpha hydrogen atom. It is a colorless volatile liquid. Synthesis Isobutyraldehyde is produced industrially by the hydroformylation of propene. Several million tons are produced annually.Boy Cornils, Richard W. Fischer, Christian Kohlpaintner "Butanals" in Ullmann's Encyclopedia of Industrial Chemistry, 2000, Wiley-VCH, Weinheim. Biological routes In the context of butanol fuel, isobutyraldehyde is of interest as a precursor to isobutanol. ''E. coli'' as well as several other organisms has been genetically modified to produce isobutanol. α-Ketoisovalerate, derived from oxidative deamination of valine, is prone to decarboxylation to give isobutyraldehyd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofuel
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. According to the United States Energy Information Administration (EIA), biofuels are mostly used for transportation, but can also be used for heating and electricity. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste. The greenhouse gas mitigation potential of biofuel varies considerably, from emission levels comparable to fossil fuels in some scenarios to negative emissions in others. See the biomass article for more on this particular subject. The two most common types of biofuel are bioethanol and biodiesel. The U.S. is the largest producer of bioethanol, while the EU is the largest producer of biodiesel. The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively. * Bioethanol is an alcohol made by fermen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isobutanol
Isobutanol (IUPAC nomenclature: 2-methylpropan-1-ol) is an organic compound with the formula (CH3)2CHCH2OH (sometimes represented as ''i''-BuOH). This colorless, flammable liquid with a characteristic smell is mainly used as a solvent either directly or as its esters. Its isomers are 1-butanol, 2-butanol, and ''tert''-butanol, all of which are important industrially. Production Isobutanol is produced by the carbonylation of propylene. Two methods are practiced industrially, hydroformylation is more common and generates a mixture of isobutyraldehyde and butyraldehyde: :CH3CH=CH2 + CO + H2 → CH3CH2CH2CHO The reaction is catalyzed by cobalt or rhodium complexes. The resulting aldehydes are hydrogenated to the alcohols, which are then separated. In Reppe carbonylation, the same products are obtained, but the hydrogenation is effected by the water-gas shift reaction.. Laboratory synthesis Propanol and methanol can be reacted to produce isobutyl alcohol via Guerbet cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-Ketovaleric Acid
α-Ketovaleric acid is a keto acid that is found in human blood. Unlike related keto acids, it is not an intermediate or metabolite associated with amino acids and its origin is unknown. See also * α-Ketoisovaleric acid * 3-Oxopentanoic acid 3-Oxopentanoic acid, or ''beta''-ketopentanoate, is a 5-carbon ketone body. It is made from odd carbon fatty acids in the liver and rapidly enters the brain. As opposed to 4-carbon ketone bodies, ''beta''-ketopentanoate is anaplerotic reaction ... (β-ketovaleric acid) * Levulinic acid (γ-ketovaleric acid) References Alpha-keto acids {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
