Glycosides

A glycoside is the molecule in which a sugar group is connected through its anomeric carbon to different group via a glycosidic bond. Glycosides can be classified by the glycone, by the type of glycosidic bond, and by the aglycone. Glycosides are also classified according to the chemical nature of the aglycone. For different purposes of biochemistry and pharmacology, this is the most useful classification. The first glycoside ever identified was amygdalin. The term 'glycoside' is now extended to also cover compounds with bonds formed between hemiacetal (or hemiketal) groups of sugars and several chemical groups other than hydroxyls, such as -SR i.e. thioglycosides, -SeR i.e.selenoglycosides, -NR1R2 i.e. N-glycosides, or even -CR1R2R3i.e. C- glycosides.