|
Sugar Acid
A Sugar acid or acidic sugar is a monosaccharide with a carboxyl group at one end or both ends of its chain. Main classes of sugar acids include: * Aldonic acids, in which the aldehyde group (−CHO) located at the initial end ( position 1) of an aldose is oxidized. * Ulosonic acids, in which the −CH2(OH) group at the initial end of a 2- ketose is oxidized creating an α- ketoacid. * Uronic acids, in which the −CH2(OH) group at the terminal end of an aldose or ketose is oxidized. * Aldaric acids, in which both ends (−CHO and −CH2(OH)) of an aldose are oxidized. Examples Examples of sugar acids include: * Aldonic acids ** Glyceric acid (3C) ** Xylonic acid (5C) ** Gluconic acid (6C) ** Ascorbic acid (6C, unsaturated lactone) * Ulosonic acids ** Neuraminic acid (5-amino-3,5-dideoxy-D- ''glycero''-D- ''galacto''-non-2-ulosonic acid) ** Ketodeoxyoctulosonic acid (KDO or 3-deoxy-D- ''manno''-oct-2-ulosonic acid) * Uronic acids ** Glucuronic acid (6C) ** Galacturonic acid ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monosaccharide
Monosaccharides (from Greek '' monos'': single, '' sacchar'': sugar), also called simple sugars, are the simplest forms of sugar and the most basic units (monomers) from which all carbohydrates are built. They are usually colorless, water- soluble, and crystalline solids. Contrary to their name (sugars), only some monosaccharides have a sweet taste. Most monosaccharides have the formula (though not all molecules with this formula are monosaccharides). Examples of monosaccharides include glucose (dextrose), fructose (levulose), and galactose. Monosaccharides are the building blocks of disaccharides (such as sucrose and lactose) and polysaccharides (such as cellulose and starch). The table sugar used in everyday vernacular is itself a disaccharide sucrose comprising one molecule of each of the two monosaccharides D-glucose and D-fructose. Each carbon atom that supports a hydroxyl group is chiral, except those at the end of the chain. This gives rise to a number of isome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylonic Acid
Xylonic acid is a sugar acid that can be obtained by oxidation of the hemiacetal/aldehyde group of xylose. The C-2 epimer is known as lyxonic acid. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccharic Acid
Saccharic acid, also called glucaric acid, is a chemical compound with the formula C6H10O8. It is derived by oxidizing a sugar such as glucose with nitric acid. at NIST The salts of saccharic acid are called saccharates or glucarates. See also * * * * * |
Mucic Acid
Mucic acid, C6H10O8 or HOOC-(CHOH)4-COOH (also known as galactaric or meso-galactaric acid) is an aldaric acid obtained by nitric acid oxidation of galactose or galactose-containing compounds such as lactose, dulcite, quercite, and most varieties of gum. Properties Mucic acid forms a crystalline powder, which melts at 210–230 °C. It is insoluble in alcohol, and nearly insoluble in cold water. Due to the symmetry in the molecule, it is optically inactive even though it has chiral carbon atoms (i.e., it is a meso compound). Reactions When heated with pyridine to 140 °C, it is converted into allomucic acid. When digested with fuming hydrochloric acid for some time it is converted into αα′ furfural dicarboxylic acid while on heating with barium sulfide it is transformed into a thiophene carboxylic acid. The ammonium salt yields on dry distillation carbon dioxide, ammonia, pyrrol and other substances. The acid when fused with caustic alkalis yields oxalic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iduronic Acid
-Iduronic acid (IUPAC abbr.: IdoA) is the major uronic acid component of the glycosaminoglycans (GAGs) dermatan sulfate, and heparin. It is also present in heparan sulfate, although here in a minor amount relative to its carbon-5 epimer glucuronic acid. IdoA is a hexapyranose sugar. Most hexapyranoses are stable in one of two chair conformations 1C4 or 4C1. -iduronate is different and adopts more than one solution conformation, with an equilibrium existing between three low-energy conformers. These are the 1C4 and 4C1 chair forms and an additional 2S0 skew-boat conformation. IdoA may be modified by the addition of an ''O''-sulfate group at carbon position 2 to form 2-''O''-sulfo--iduronic acid (IdoA2S). In 2000, LK Hallak described the importance of this sugar in respiratory syncytial virus (RSV) infection. Dermatan sulfate and heparan sulfate were the only GAGs containing IdoA, and they were the only ones that inhibited RSV infection in cell culture. When internally posi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galacturonic Acid
-Galacturonic acid is a sugar acid, an oxidized form of galactose, -galactose. It is the main component of pectin, in which it exists as the polymer polygalacturonic acid.Debra Mohnen "Pectin structure and biosynthesis" Current Opinion in Plant Biology 2008, 11:266–277. . In its open form, it has an aldehyde group at C1 and a carboxylic acid group at C6. Other oxidized forms of -galactose are -galactonic acid (carboxylic group at C1) and ''meso''-galactaric acid (mucic acid) (carboxylic groups at C1 and C6). It is also a uronic acid or hexuronic acid. Naturally occurring uronic acids are -glucuronic acid, -galacturonic acid, -iduronic acid and -mannuronic acid. References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucuronic Acid
Glucuronic acid (from Greek γλεῦκος "''wine, must''" and οὖρον "''urine''") is a uronic acid that was first isolated from urine (hence the name). It is found in many gums such as gum arabic (c. 18%), xanthan, and kombucha tea and is important for the metabolism of microorganisms, plants and animals. Properties Glucuronic acid is a sugar acid derived from glucose, with its sixth carbon atom oxidized to a carboxylic acid. In living beings, this primary oxidation occurs with UDP-α-D-glucose (UDPG), not with the free sugar. Glucuronic acid, like its precursor glucose, can exist as a linear (carboxo-)aldohexose ( 60,000 are too large for renal excretion and will be excreted with bile into the intestine. Neonates are deficient in this conjugating system, making them particularly vulnerable to drugs such as chloramphenicol, which is inactivated by the addition of glucuronic acid, resulting in gray baby syndrome. Bilirubin is excreted in the bile as bilirubin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannose
Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation are associated with mutations in enzymes involved in mannose metabolism. Mannose is not an essential nutrient; it can be produced in the human body from glucose, or converted into glucose. Mannose provides 2–5 kcal/g. It is partially excreted in the urine. Etymology The root of both "mannose" and "mannitol" is manna, which the Bible describes as the food supplied to the Israelites during their journey in the region of Sinai. Several trees and shrubs can produce a substance called manna, such as the "manna tree" ('' Fraxinus ornus'') from whose secretions mannitol was originally isolated. Structure Mannose commonly exists as two different-sized rings, the pyranose (six-membered) form and the furanose (five-membered) form. E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketodeoxyoctulosonic Acid
3-Deoxy--''manno''-oct-2-ulosonic acid (ketodeoxyoctonic acid; KDO; IUPAC symbol Kdo) is an ulosonic acid of a 2-ketooctose which is used by bacteria in the synthesis of lipopolysaccharides. The -''manno'' prefix indicates that the four chiral centers have the same configuration as -mannose Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation .... References Sugar acids {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galactose
Galactose (, '' galacto-'' + ''-ose'', "milk sugar"), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molecule linked with a glucose molecule forms a lactose molecule. Galactan is a polymeric form of galactose found in hemicellulose, and forming the core of the galactans, a class of natural polymeric carbohydrates. D-Galactose is also known as brain sugar since it is a component of glycoproteins (oligosaccharide-protein compounds) found in nerve tissue. Etymology The word ''galactose'' was coined by Charles Weissman in the mid-19th century and is derived from Greek ''galaktos'' (of milk) and the generic chemical suffix for sugars ''-ose''. The etymology is comparable to that of the word ''lactose'' in that both contain roots meaning "milk sugar". Lactose is a disaccharide of galactose plus glucose. Structure and isomerism Galactose exists in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glyceraldehyde
Glyceraldehyde (glyceral) is a triose monosaccharide with chemical formula C3 H6 O3. It is the simplest of all common aldoses. It is a sweet, colorless, crystalline solid that is an intermediate compound in carbohydrate metabolism. The word comes from combining glycerol and aldehyde, as glyceraldehyde is glycerol with one alcohol group oxidized to an aldehyde. Structure Glyceraldehyde has one chiral center and therefore exists as two different enantiomers with opposite optical rotation: * In the nomenclature, either from Latin ''Dexter'' meaning "right", or from Latin ''Laevo'' meaning "left" * In the R/S nomenclature, either R from Latin ''Rectus'' meaning "right", or S from Latin ''Sinister'' meaning "left" While the optical rotation of glyceraldehyde is (+) for ''R'' and (−) for ''S'', this is not true for all monosaccharides. The stereochemical configuration can only be determined from the chemical structure, whereas the optical rotation can only be determined e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuraminic Acid
Neuraminic acid (5-amino-3,5-dideoxy-D-''glycero''-D-''galacto''-non-2-ulosonic acid) is an acidic (in particular ulosonic) amino sugar with a backbone formed by nine carbon atoms. Although 9-carbon sugars do not occur naturally, neuraminic acid may be regarded as a theoretical 9-carbon ketose in which the first link of the chain (the –CH2OH at position 1) is oxidised into a carboxyl group (–C(=O)OH), the hydroxyl group at position 3 is deoxidised (oxygen is removed from it), and the hydroxyl group at position 5 is substituted with an amino group (–NH2). Neuraminic acid may also be visualized as the product of an aldol-condensation of pyruvic acid and D-mannosamine (2-amino-2-deoxy-mannose). Neuraminic acid does not occur naturally, but many of its derivatives are found widely distributed in animal tissues and in bacteria, especially in glycoproteins and gangliosides. The ''N''- or ''O''-substituted derivatives of neuraminic acid are collectively known as siali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
