This is C-1 in aldoses, and C-2 in the case of fructose. The two anomers are described with the terms α (“alpha”) and β (“beta”), defined above.Īnomeric carbon – the carbon of a cyclic sugar bearing a hemiacetal or acetal (hemiketal or ketal). If these names sound familiar, it is because alditols are commonly used as food additives and sweeteners.Īnomer – the name given to two diastereomeric monosaccharides that are epimers at the anomeric carbon. Sorbitol is the alditol of glucose, mannitol is the alditol of mannose, and so forth.

The alditol of glyceraldehyde, for example, is glycerol. Contrast aldoses with ketoses, which are monosaccharides with a ketone (or masked ketone) group.Īlditol – an acyclic alcohol derived from the reduction of an aldose. from the action of nitric acid:Īldose – a monosaccharide with an aldehyde (or masked aldehyde) functional group. Contrasted with beta (β) which is where the two substituents are on the same faces of the ring.Īldaric acid – a dicarboxylic acid derived from an aldose where both ends of the sugar have been oxidized, e.g. Α (Alpha) – the name given to the configuration of a cyclic sugar where the oxygen on the anomeric carbon is on the opposite face of the ring relative to the substituent on the other carbon flanking the ring oxygen. Feedback on anything that is missing would be greatly appreciated. Man, is there ever a lot of sugar nomenclature to know! This post aims to provide single place giving you the definitions of terms like anomeric carbon, alpha versus beta, pyranose versus furanose, and all the other most commonly encountered carbohydrate-related terms in a typical second-semester organic chemistry course.

Galactose anomeric carbon