Aldose: Difference between revisions
m Removed invisible unicode characters + other fixes, replaced: → (2) using AWB (11347) |
Magioladitis (talk | contribs) ++ |
||
Line 1: | Line 1: | ||
[[ |
[[File:D-Glyceraldehyde 2D Fischer.svg|thumb|140px|[[Fischer projection]] of {{small|D}}-[[glyceraldehyde]]]] |
||
An '''aldose''' is a [[monosaccharide]] (a simple sugar) that contains only one [[aldehyde]] (−CH=O) group per [[molecule]]. The [[chemical formula]] takes the form C<sub>''n''</sub>(H<sub>2</sub>O)<sub>''n''</sub>. The simplest possible aldose is the [[diose]] [[glycolaldehyde]], which only contains three [[carbon]] [[atom]]s.<ref>{{cite book| last=Berg| first=J.M.| edition=6th| title=Biochemistry| year=2006| publisher=W. H. Freeman and Company| location=New York}}</ref> |
An '''aldose''' is a [[monosaccharide]] (a simple sugar) that contains only one [[aldehyde]] (−CH=O) group per [[molecule]]. The [[chemical formula]] takes the form C<sub>''n''</sub>(H<sub>2</sub>O)<sub>''n''</sub>. The simplest possible aldose is the [[diose]] [[glycolaldehyde]], which only contains three [[carbon]] [[atom]]s.<ref>{{cite book| last=Berg| first=J.M.| edition=6th| title=Biochemistry| year=2006| publisher=W. H. Freeman and Company| location=New York}}</ref> |
Revision as of 20:25, 30 July 2015
An aldose is a monosaccharide (a simple sugar) that contains only one aldehyde (−CH=O) group per molecule. The chemical formula takes the form Cn(H2O)n. The simplest possible aldose is the diose glycolaldehyde, which only contains three carbon atoms.[1]
Because they have at least one asymmetric carbon center, aldoses with three or more carbon atoms exhibit stereoisomerism. Aldoses containing stereogenic centers can exist in either a D- form or L- form. The determination is made based on the chirality of the penultimate carbon (the second-furthest from the aldehyde), where alcohol groups on the right of the Fischer projection result in D-aldoses, and epimers with alcohols on the left result in L-aldoses. Biological systems tend to recognize D-aldoses more than L-aldoses.
An aldose differs from a ketose in that it has a carbonyl group at the end of the carbon chain instead of in the middle. This allows ketoses and aldoses to be chemically differentiated through Seliwanoff's test.[2] An aldose may isomerize to a ketose through the Lobry-de Bruyn-van Ekenstein transformation.[3]
List of aldoses
- Diose: glycolaldehyde
- Triose: glyceraldehyde
- Tetroses: erythrose, threose
- Pentoses: ribose, arabinose, xylose, lyxose
- Hexoses: allose, altrose, glucose, mannose, gulose, idose, galactose, talose
See also
References
- ^ Berg, J.M. (2006). Biochemistry (6th ed.). New York: W. H. Freeman and Company.
- ^ "Seliwanoff's Test". Harper College. Retrieved 2011-07-10.
- ^ "Lobry de Bruyn-van Ekenstein Transformation". Drug Future. Retrieved 2011-07-10.