Continued from 2-Carb-29 and 2-Carb-30
2-Carb-31.1. Glycosyl residues
The residue formed by detaching the anomeric hydroxy group from a monosaccharide is named by replacing the terminal '-e' of the monosaccharide name by '-yl'. The general name is 'glycosyl' residue. Terms of this type are widely used in naming glycosides and oligosaccharides. For examples (including glycosyl residues from uronic acids), see 2-Carb-33.2. The term 'glycosyl' is also used in radicofunctional names, e.g. for halides such as the glucopyranosyl bromide in 2-Carb-24.1 and the mannopyranosyl fluoride in 2-Carb-16.1, and esters such as the glucopyranosyl phosphate in 2-Carb-24.2.1 and the mannopyranosyl nitrate in 2-Carb-16.2.
2-Carb-31.2 Monosaccharides as substituent groups
In order to produce names for structures in which it may be desirable for a non-carbohydrate portion to be cited as parent, prefix terms are required for carbohydrate residues linked through carbon or oxygen at any position on the main chain. These prefixes can be formed by replacing the final 'e' of the systematic or trivial name of a monosaccharide by '-n-C-yl', '-n-O-yl' or '-n-yl' (if there is no ambiguity). In each case the term '-yl' signifies loss of H from position n. At a secondary position (e.g. in 2-deoxy-D-glucos-2-yl, below) the free valency is regarded as equivalent to OH for assignment of configuration.
The same endings can be used to form substituent prefixes for alditol residues.
L-Arabinitol-1-C-yl (cf. 2-Carb-18.4)
(R/S to be specified at C-1)
The ending '-yl' without a locant signifies loss of OH from the anomeric position (see 2-Carb-31.1). Loss of H from the anomeric OH is indicated by the ending '-yloxy', without a locant. For examples see 2-Carb-33.
The situation in which the anomeric OH is retained but H is lost from the anomeric carbon atom is indicated by use of the ending '-yl' without a locant in conjunction with the prefix '1-hydroxy-' (not by the ending '-1-C-yl'). N.B. In this case, the anomeric prefix α or β refers to the free valency, not the OH group.
Examples of the use of substituent prefixes for carbohydrate residues:
[trivial name S-adenosylmethionine (SAM)]
(more commonly named 2-O-carboxymethyl-β-D-glucopyranose;
see 2-Carb-2.1, note 2)
(Methyl α-D-glucopyranosid-4-O-yl)pyruvic acid
[or methyl 4-O-(oxalomethyl)-α-D-glucopyranoside]
3-(β-D-Glucopyranosyloxy)indole (or indol-3-yl β-D-glucopyranoside);
trivial name indican
X = O
Methyl 2-O-(methyl 2-deoxy-α-D-glucopyranosid-2-yl)-α-D-glucopyranoide
or bis(methyl 2-deoxy-α-D-glucopyranosid-2-yl) ether
X = NH
2-Carb-31.3. Bivalent and tervalent groups
The group formed by detaching one hydrogen atom from each of two (or three) carbon atoms of a monosaccharide is named by adding to the monosaccharide name '-diyl' (or '-triyl'), preceded by the appropriate locants.
Methyl (ethyl 2,4-dideoxy-β-D-glucopyranoside-2,4-diyl)phosphinite
or ethyl 2,4-dideoxy-2,4-(methoxyphosphanediyl)-β-D-glucopyranoside
Residues formed by detaching two (or three) hydrogen atoms from the same carbon atom may be named similarly.
Note. Names based on phosphane, rather than phosphine or phosphorane, are used in this document, as recommended in .
14. Guide to IUPAC Nomenclature of Organic Compounds, Recommendations 1993, Blackwell Scientific Publications, Oxford (1993).
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