Haworth projection

A Haworth projection of the structure for α-D-glucopyranose

A Haworth projection is a common way of representing the cyclic structure of monosaccharides with a simple three-dimensional perspective.

The Haworth projection was named after the English chemist Sir Norman Haworth.

A Haworth projection has the following characteristics:^[1]

• Carbon is the implicit type of atom. In the example on the right, the atoms numbered from 1 to 6 are all carbon atoms. Carbon 1 is known as the anomeric carbon.
• Hydrogen atoms on carbon are implicit. In the example, atoms 1 to 6 have extra hydrogen atoms not depicted.
• A thicker line indicates atoms that are closer to the observer. In the example on the right, atoms 2 and 3 (and their corresponding OH groups) are the closest to the observer. Atoms 1 and 4 are farther from the observer. Atom 5 and the other atoms are the farthest.
• The groups below the plane of the ring in Haworth projections are equivalent to those on the right-hand side of a Fischer projection.

See also

• Structural formula
• Fischer projection
• Natta projection
• Newman projection
• Monosaccharide

References

1. ↑ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version:  (2006–) "Haworth representation".