Pyranose

Pyranose is a collective term for carbohydrates that have a chemical structure that resembles a pyran ring. This term is derived from the combination of "pyran" and "ose," the latter being a common suffix for sugars. Pyranose forms of various sugars are often found in nature.

Structure

The structure of a pyranose sugar is characterized by a six-membered ring consisting of five carbon atoms and one oxygen atom. The carbon atoms are numbered from 1 to 5, with the oxygen atom taking the 6th position. The first carbon atom is attached to a hydroxyl group (-OH), and the remaining carbon atoms are each attached to a hydrogen atom and a hydroxyl group.

Formation

Pyranose forms of sugars are created through a process known as ring closure. This occurs when the hydroxyl group on the fifth carbon atom reacts with the carbonyl group on the first carbon atom, forming a hemiacetal. This reaction is reversible, and the equilibrium between the open-chain and pyranose forms of a sugar depends on the specific sugar and the conditions.

Examples

Common examples of pyranose sugars include glucose, galactose, and mannose. These sugars exist predominantly in their pyranose forms in aqueous solution.

See also

• Furanose
• Haworth projection
• Monosaccharide
• Disaccharide

• TetrahydroPYRANE V.1
  TetrahydroPYRANE V.1
• TetrahydroPYRANE V.2
  TetrahydroPYRANE V.2
• Representations of glucopyranose
  Representations of glucopyranose
• Haworth Projection
  Haworth Projection
• Glucopyranose Conformations (linear format)
  Glucopyranose Conformations (linear format)
• Relative Conformation Energies
  Relative Conformation Energies
• Pyranose Nomenclature Example
  Pyranose Nomenclature Example