General Index


Monosaccharide Derivatives

Index


Oxidation derivatives


If the oxidation takes place at carbon 1, the derivatives are called Aldonic Acids. In the case of D-Glucose, we get

That appears as gluconate. In the Fischer projection,

Aldonic acids can form intramolecular esters or Lactones. In the case of Gluconic acid, an ester between carbons 1 and 5 gives

In the Haworth perspective,

Among these derivatives we can consider Ascorbic Acid:

Also known as Vitamin C. Its structure is:



When the oxidation takes place at carbon 6, the derivatives are called Uronic Acids. In the case of D-Glucose, we get D-Glucuronic Acid:

A relevant biomolecule in Detoxification processes:


The C6-epimer of Glucuronic acid is

Both acids enter in the composition of Glycosaminoglycans. The structure of Iduronic Acid is:



Reduction Derivatives

Carbonyl groups in aldoses or ketoses can be reduced and the resulting compound is a polyalcohol. In the case of D-Glucose, the polyalcohol is


In Fischer projection, its structure is

The result of the reduction of D-Mannose is


In the Fischer projection, the structure of Mannitol is:

Reduction of trioses (Glyceraldehyde or Glycerone) we obtain


Having no asymmetrical carbons, we adopt the sn convention. If we place the molecule with carbon 2 in the same configuration as L-Glyceraldehyde, carbon sn-1 is up and carbon sn-3 is down. Carbon sn-2 is the secondary alcohol. In Fischer projection formula,




Deoxysugars


When we substitute a hydroxyl group -OH in a monosaccharide by an hydrogen -H, the resulting compounds are Deoxysugars. An important one is the 2-deoxy derivative of D-Ribose,

that forms part of Deoxynucleotides, the monomers of DNA (Deoxyribonucleic Acid). Its structure is


Other deoxyderivatives are


Or 6-deoxy-L-Mannose:

And also

Or 6-deoxy-L-galactose. Its structure is:

Both appear in complex oligo- and polysaccharides.




Aminosugars


Aminoderivatives arise when we substitute a hydroxyl -OH group by an amino -NH2. This group normally appears acetylated. This is the case of

Whose structure is:

As well as


Its structure being

They appear in complex oligo- and polysaccharides.


An important aminoderivative is

also known as N-Acetyl Neuraminic Acid (NANA). It appears in complex oligosaccharides and glycoconjugates (Glycolipids, Glycoproteins). its structure is




Phosphoric Esters


The metabolically-active forms of sugars are phosphoric esters. Thus, D-Glucose forms

Its structure is:


Other form is the hemiacetal phosphate

Its structure being


D-Fructose also forms phosphoric esters. For instance,

Whose structural formula is:


Also the bisphosphate

In Haworth perspective is:



Other interesting phosphoric ester is

its structure is:

It is a key intermediate in the dark phase of Photosynthesis.




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