Gulose

Definition
noun
An aldohexose monosaccharide that is C-3 epimer of galactose
Supplement
Monosaccharides are the simplest form of carbohydrates. They may be classified based on the number of constituent carbon atoms. For instance, hexose is a monosaccharide with six carbon atoms. They may be further classified based on the functional group present. An aldose is a sugar with an aldehyde functional group whereas a ketose is a sugar with a ketone functional group. Gulose is one of the hexose monosaccharides and it belongs to the aldoses.
Gulose, particularly D-gulose is a C-3 epimer of D-galactose. Galactose is an aldohexose similar to glucose in terms of chemical structure. This means that they have similar chemical formula: C₆H₁₂O₆. Galactose does not occur in free state and is usually found as a constituent of complex biomolecules (e.g. lactose, galactan). Gulose, unlike galactose, is very rare in nature.
L-gulonic acid, the oxidation product of L-gulose, serves as a precursor of ascorbic acid (except in primates, guinea pigs, certain fishes, and the indian fruit bat) via L-gulonolactone.
Gulose is syrupy, with a sweet taste. It is water soluble and slightly soluble in methanol.
IUPAC name:

• (3R,4R,5R,6R)-6-(Hydroxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetraol

Chemical formula:

C₆H₁₂O₆

See also:

• monosaccharide
• galactose
• stereoisomer

Related term(s):

L-gulonic acid