glyceraldehyd

Glyceraldehyde (German: glyceraldehyd) is the simplest aldose, a triose carbohydrate with the molecular formula C3H6O3. It exists as two enantiomers, D-glyceraldehyde and L-glyceraldehyde, which are non-superimposable mirror images. The D form is the reference for assigning the D/L configuration to other sugars.

In its open-chain form, glyceraldehyde has the structure CHO-CHOH-CH2OH. The stereocenter is at carbon 2; in the Fischer projection, the hydroxyl on C2 is on the right for D-glyceraldehyde and on the left for L-glyceraldehyde. Because the chain is short, glyceraldehyde predominantly remains in the open-chain form in solution rather than forming cyclic structures typical of longer sugars.

Glyceraldehyde is a reducing sugar and can undergo oxidation to glyceric acid or reduction to glycerol. It is a fundamental reference compound in carbohydrate chemistry and biochemistry for defining stereochemistry and for studying reactions of aldoses. In metabolism, the phosphorylated derivative glyceraldehyde-3-phosphate (GAP) is a central intermediate in glycolysis and the Calvin cycle; glyceraldehyde itself is not a primary metabolic intermediate, but the triose family links several metabolic pathways.

Occurrence and synthesis: glyceraldehyde occurs in trace amounts in nature and can be prepared synthetically by oxidation of glycerol or via hydrolysis of certain glycerol derivatives. It serves as a building block for the synthesis of other sugars and sugar phosphates.

Safety and handling: as a laboratory chemical, glyceraldehyde should be handled with standard precautions appropriate to organic aldehydes.