Bonds in disaccharides

Zegota H, von Sonntag C (1977) Radiation chemistry of carbohydrates, XV. OH radical induced scission of the glycosidic bond in disaccharides. Z Naturforsch 32b 1060-1067... 

Thble 9.3. Intramolecular inter-residue OH - O hydrogen bonds in disaccharides. These hydrogen bonds are frequently three-centered. When one of the components is intermolecular, the distance is indicated bya. With the exception of the neutron analysis, (N), the O-H covalent bond lengths have been normalized to 0.97 A... 

Table 13.3. Summary of Hydrogen Bonding in Disaccharide Crystal Structures... 

Chapter 13, Carbohydrates, describes the carbohydrate molecules monosaccharides, disaccharides, and polysaccharides and their formation by photosynthesis. Monosaccharides are classified as aldo or keto pentoses or hexoses. Chiral molecules, moved from Chapter 12 to Chapter 13, are discussed along with Eischer projections and d and l notations. An Explore Your World feature models chiral objects using gumdrops and toothpicks. Carbohydrates used as sweeteners are described and carbohydrates used in blood typing are discussed. The formation of glycosidic bonds in disaccharides and polysaccharides is described. 

Condensation of the mixture of dienes 661 and 662 with 2(R)-menthyl glyoxylate (until only the trams,trams diene had entered into reaction) gave1153 a mixture of three products (667-669) in 63% overall yield. This mixture was separated into its components. Reduction of R1 to a hydroxymethyl group in 667 and 668, and m-hydroxylation of the double bond, gave disaccharides 670 and 671, in which the newly created sugar units were identified as D- and L-gulose, respectively. 

Glycosidic bond. The bond between a sugar and an alcohol. Also the bond that links two sugars in disaccharides, oligosaccharides, and polysaccharides. 

Ethanol production from sugarcane (Saccharum sp.) is one of the easiest and most efficient processes since sugarcane contains about 15% sucrose. The glycosidic bond in the disaccharide can be broken down into two sugar units, which are free... 

Disaccharides are formed from two monosaccharide units that are connected by a gly-cosidic bond. Different disaccharides result from the combination of different monosaccharides, from the formation of the glycosidic bond using different hydroxy groups on the monosaccharides, or from different stereochemistries of the glycosidic bond. A few of the more important disaccharides are described in the following paragraph. 

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