Sugars stereoisomers

Sugar stereoisomers that differ in configuration only at the anomeric carbon. Anomers are classified as a or /3 depending on whether the anomeric hydroxyl group (or the aglycone in a glycoside) is trans (a) or cis (/3) to the terminal —CH2OH. (p. 1112)... 

Working with the Concepts Relationships Between Sugar Stereoisomers... 

Anomers (Section 25.5) Cyclic stereoisomers of sugars that differ only in their configuration at the hemiacetal (anoineric) carbon. 

Table sugar, sec Sucrose Tagatose, structure of, 975 Talose. configuration of, 982 Tamiflu, molecular model of, 130 Tamoxifen, synthesis of, 744 Till] DNA polymerase, PCR and, 1117 Tartaric acid, stereoisomers of, 305-306... 

Deoxy-2 -fluoroinosine (869) monohydrate, prepared from 867 by treatment with nitrous acid, was found " to be, in crystals, a mixture of two different stereoisomers (syn and anti orientation of the base-sugar.)... 

Sugars have large numbers of stereoisomers because they contain several asymmetric carbon atoms. 

The two forms of mirror images are called enantiomers, or stereoisomers. All amino acids in proteins are left-handed, and all sugars in DNA and RNA are right-handed. Drug molecules with chiral centers when synthesized without special separation steps in the reaction process result in 50/50 mixtures of both the left- and right-handed forms. The mixture is often referred to as a racemic mixture. 

Gefarnate, a mixture of stereoisomers, was shown to lack both water-retaining and diuretic activity, to have no effect on blood pressure, respiration, blood-sugar. 

The sugar glucose has four chiral centres therefore, 2 = 16 different stereoisomers of this strnctnre may be... 

With carefully selected aliphatic precursors, the synthesis of single stereoisomers of side-chain-substituted pteridines has been achieved (Schemes 20-22). The synthesis of L-biopterin 106 requires 5-deoxy-L-arabinose 102 as a key intermediate preparable from the expensive sugars L-rhamnose and L-arabinose. Alternatively, the readily... 

In living organisms, chiral molecules are usually present in only one of their chiral forms. For example, the amino acids in proteins occur only as their l isomers glucose occurs only as its D isomer. (The conventions for naming stereoisomers of the amino acids are described in Chapter 3 those for sugars, in Chapter 7 the RS system, described above, is the most useful for some biomolecules.) In contrast, when a compound with an asymmetric carbon atom is chemically synthesized in the laboratory, the reaction usually pro-... 

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