Originally mixed acetals resulting from the attachment of a glycosyl group to a non-acyl group RO– (which itself may be derived from a saccharide and chalcogen replacements thereof (RS–, RSe–). The bond between the glycosyl group and the OR group is called a glycosidic bond. By extension, the terms N-glycosides and C-glycosides are used as class names for glycosylamines and for compounds having a glycosyl group attached to a hydrocarbyl group respectively. These terms are misnomers and should not be used. The preferred terms are glycosylamines and C-glycosyl compounds, respectively.