Glycosyl

File:Beta-D-Glucopyranosyl.png

The β-D-glucopyranosyl group which is obtained by the removal of the hemiacetal hydroxyl group (bottom right) from β-D-glucopyranose

In organic chemistry, a glycosyl group is a univalent free radical or substituent structure obtained by removing the hydroxyl (Template:Chem2) group from the hemiacetal (Template:Chem2) group found in the cyclic form of a monosaccharide and, by extension, of a lower oligosaccharide. Glycosyl groups are exchanged during glycosylation from the glycosyl donor, the electrophile, to the glycosyl acceptor, the nucleophile.<ref>Template:Cite journal</ref> The outcome of the glycosylation reaction is largely dependent on the reactivity of each partner.<ref>Template:Cite journal</ref> Glycosyl also reacts with inorganic acids, such as phosphoric acid, forming an ester such as glucose 1-phosphate.<ref>Template:Cite journal</ref>

Examples

In cellulose, glycosyl groups link together 1,4-β-D-glucosyl units to form chains of (1,4-β-D-glucosyl)_n. Other examples include ribityl in 6,7-Dimethyl-8-ribityllumazine, and glycosylamines.

Alternative substituent groups

File:Beta-D-Glucopyranos-3-O-yl.png

The β-D-glucopyranose-3-O-yl group which is obtained by the removal of a hydrogen from the C3 hydroxyl (bottom left) of β-D-glucopyranose

Instead of the hemiacetal hydroxyl group, a hydrogen atom can be removed to form a substituent, for example the hydrogen from the C3 hydroxyl of a glucose molecule. Then the substituent is called D-glucopyranos-3-O-yl as it appears in the name of the drug Mifamurtide.

Recent detection of Au³⁺ in vivo used C-glycosyl pyrene. Its fluorescence and permeability through cell membranes helped detect Au³⁺.<ref>Template:Cite journal</ref>

See also

• Acyl group