Systematic nomenclature for oligosaccharides, which differs between non-reducing and reducing sugars. Non-reducing sugars are named according to their glycosides. For example, sucrose is a non-reducing disaccharide and can be named as glucoside or fructoside. As shown in Figure "Systematic Naming of Sucrose", both names are correct. The glycosidic bond is formed between two hemiacetal hydroxyl groups, and the position is definite and does not need to be indicated by numbers.
The nomenclature of non-reducing oligosaccharides with more than trisaccharides is similar to that of disaccharides, in a glycosyl-glycosyl-glycosidic manner. The relevant carbon atoms of the glycosidic linkage are indicated by two numbers, placed between the names of the glycosyl groups, within a bracket, and separated by arrows, the direction of which is from the hemiacetal hydroxyl carbon atom to the alcohol hydroxyl carbon atom.
The systematic naming of reducing disaccharides is carried out in accordance with the substitution of one sugar group for the alcoholic hydroxyl group of another monosaccharide, starting with the non-reducing sugar group, the position of the substituted alcoholic hydroxyl group is indicated by a number, and the name of the substituted sugar is added. The relevant carbon atoms of the glycosidic bond can also be indicated by two numbers, placed in parentheses, separated by arrows, the direction of which is from the hemiacetal hydroxyl carbon atom to the alcohol hydroxyl carbon atom.
Reducing oligosaccharides above disaccharides, the systematic nomenclature is similar to disaccharides. Proceed in a glycosyl-glycosyl-sugar fashion. Beginning with the name of the non-reducing sugar, another sugar name is listed in order, and finally the name of the reducing sugar, and the position of the connecting carbon atom is indicated by brackets and numbers between the sugar name and the sugar name.
