Carb-22. Uronic Acids

2-Carb-22. Uronic acids 2-Carb-22.1. Naming and numbering 

The names of the individual compounds of this type are formed by replacing (a) the -ose of the systematic or trivial name of the aldose by -uronic acid , (b) the -oside of the name of the glycoside by -osiduronic acid or (c) the -osyl of the name of the glycosyl group by -osy luronic acid . The carbon atom of the (potential) aldehydic carbonyl group (not that of the carboxy group as in normal systematic nomenclature [13,14]) is numbered 1 (see 2-Carb-2.1, note 1). 

Derivatives of these acids formed by change in the carboxy group (salts, esters, lactones, acyl halides, amides, nitriles, etc.) are named according to 2-Carb-20.2. The anion takes the ending -uronate . Esters are also named using the ending -uronate . 

Phenyl p-D-glucopyranosiduronic acid not phenyl p-D-glucuronoside or phenyl glucuronide H 

Methyl (phenyl 4-deoxy-p-L-fhreo-hex-4-enopyranosid)uronate 

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Monocarboxylic acids formally derived from aldoses by replacement of the CH2OH group with a carboxy group are termed uronic acids (see 2-Carb-22). 

Note 1. To maintain homomorphic relationships between classes of sugars, the (potential) aldehyde group of a uronic acid is regarded as the principal function for numbering and naming (see 2-Carb-2.2.1 and 2-Carb-22). 

A (potential) aldehyde group receives the locant 1 (even if a senior function is present, as in uronic acids see 2-Carb-2.1, note 1) ... 

The IUPAC-IUBMB short form symbolism18 2-Carb-38.5 is used here and elsewhere in this chapter for designation of oligosaccharide structures. Parent monosaccharide residues are the d enantiomers except for IdoA, which is the l enantiomer. Uronic acid residues modified by 44-unsaturation are prefixed by A4tS, and the associated anomeric symbol relates to the configuration at the 5-position of that residue before 4,5-elimination. The abbreviation HexA is used to denote either d-G1cA or L-IdoA. 

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