Dhexoses

Dhexoses are a class of carbohydrates that are isomers of hexose sugars, meaning they have the same chemical formula (C6H12O6) but differ in the arrangement of their atoms. Specifically, dhexoses are stereoisomers of hexoses and are characterized by the orientation of their hydroxyl groups. In the D-configuration, the hydroxyl group on the penultimate carbon atom (the carbon furthest from the carbonyl group) is on the right side when the sugar molecule is drawn in a Fischer projection.

The most common and biologically significant dhexoses are D-glucose, D-fructose, D-galactose, and D-mannose. D-glucose is the primary source of energy for most living organisms and is a fundamental component of many polysaccharides like starch and cellulose. D-fructose, often called fruit sugar, is found in fruits and honey and is sweeter than glucose. D-galactose is a component of lactose, the sugar found in milk, and is also a part of several complex carbohydrates. D-mannose is a sugar found in some glycoproteins and is involved in cell recognition processes.

These dhexoses can exist in linear or cyclic forms. In aqueous solutions, they predominantly form cyclic hemiacetal or hemiketal structures. The interconversion between the linear and cyclic forms is a key aspect of their chemistry and biological function. Dhexoses play crucial roles in metabolism, cellular structure, and signaling pathways in a wide variety of organisms.