Monosaccharides residue naming

Carb-29. Hemiacetals and hemithioacetals 2-Carb-30. Acetals, ketals and their thio analogues 2-Carb-31. Names for monosaccharide residues... 

Symbols for the common monosaccharide residues and derivatives are listed in Table 2. They are generally derived from the corresponding trivial names. Abbreviations for substituents (see 2-Carb-1.16.2), preceded by locants, follow the monosaccharide abbreviations directly. 

A general term for a polysaccharide (glycan) composed of a single type of monosaccharide residue is obtained by replacing the ending -ose of the sugar name by -an . 

Table 9.1 Names of monosaccharide residues used in biochemistry and precise nomenclature.

Monosaccharide residues are named and abbreviated (Table I) according... 

Using the condensed system of carbohydrate nomenclature (ref. 2, section 3.7 ref. 4, 2-Carb-38.5), positions of glycosidic linkages and anomeric configurations are expressed in parentheses between the monosaccharide residues that are thus linked. This principle should be adhered to with full names as well as with the abbreviated structures. A short form for repre-... 

A system already used (GL-5.3) is based on the abbreviated root names of the oligosaccharide structures. The full root structures are telrasaccha-rides. and sequential removal of terminal monosaccharide residues gives smaller, precisely defined structures. Elongation of root tetrasaccharidcs is, on the other hand, undefined and hence ambiguous. The root name may be used, followed by an arabic number indicating the total number of monosaccharide residues. A lowercase letter can be added to differentiate between particular compounds. 

The following table lists the systematic names and symbols for selected carbohydrates and some of their derivatives. The symbols for monosaccharide residues and derivatives are recommended by lUPAC for use in describing the structures of oligosaccharide chains. A more complete list can be found in the reference. 

Since the word nucleotide refers to a carbohydrate molecule containing a single monosaccharide residue, the name of NAD+ indicates two monosaccharide residues (riboses) on the compound. In contrast to nucleotides in a polynucleotide chain such as RNA, the two nucleotides are joined. While one of the nucleotides contains an adenine moiety (as in ATP, Fig. 10-2,) the other nucleotide has a nicotinamide moiety. It is this part of NAD+ that receives a hydrogen atom from a fuel molecule, reducing it to NADH. 

The term sugar is generally restricted to those carbohydrates containing fewer than ten monosaccharide residues, while the name oligosaccharides (from the Greek oligos, a few) is frequently used to include all sugars other than the monosaccharides. 

The partially methylated monosaccharides obtained on depolymerization of the permethylated sample are preferably analyzed as acetates by g.l.c.-m.s., as shown by Bjomdal and coworkers.41,42 The neutral sugars and the amino sugars obtained in acetolysis-acid hydrolysis are reduced, and acetylated for the analysis, and the amino-hexitol and the neuraminic acid residues are acetylated after methanolysis. Identification with the aid of g.l.c.-m.s. has been described for all of the common components of protein- and lipid-linked glycans and oligosaccharides from animal cells, namely, the neutral sugars,41-43 hexitols,44 hexosamines,29,43,45,46 aminohexitols,31,32 and neuraminic acids.33,34,47... 

---