Glycosidic linkage in disaccharides is formed by the loss of a water molecule, connecting two monosaccharide units through an oxygen atom. It results from the bonding of the reducing groups (aldehydic or ketonic) of monosaccharides.

Fructose belongs to the D-series and is a laevorotatory compound. Its open-chain structure includes a ketonic functional group at carbon number 2.

Fructose has the molecular formula C₆H₁₂O₆ and contains a ketonic functional group at carbon number 2. It shares similarities with glucose in having six carbons in a straight chain.

Fructose is obtained along with glucose by the hydrolysis of the disaccharide sucrose. It is a natural monosaccharide present in fruits, honey, and vegetables.

The existence of two crystalline forms (a and b) with different melting points (419 K and 423 K) cannot be explained by the open-chain structure (I). The proposal of a cyclic hemiacetal structure forming a six-membered ring, with —OH at ...