Ketose ketone group

Monosaccharides containing a (potential) aldehydic group and a (potential) ketonic group are called ketoaldoses (see 2-Carb-12) this term is preferred to the alternatives on the basis of 2-Carb-2.1.1 (aldose preferred to ketose). 

Monosaccharides are those carbohydrates that cannot be hydrolyzed into simpler carbohydrates They may be classified as trioses, tetroses, pentoses, hex-oses, or heptoses, depending upon the number of carbon atoms and as aldoses or ketoses depending upon whether they have an aldehyde or ketone group. Examples are listed in Table 13-1. 

Figure 4.17 The trioses D-glyceraldehyde (aldose) and dihydroxyacetone (ketose), the pentose D-ribose, the hexoses D-galactose and D-glucose (aldoses) and the ketohexose D-fructose in their open chain forms. The configuration of the asymmetrical hydroxyl group on the carbon, the furthest away from the aldehyde or ketone group, determines the assignment of D- or L-configuration.

The carbonyl group in glucose and ribose is an aldehyde such compounds are termed aldoses. Fructose, by contrast, has a ketone group and is therefore classified as a ketose. Glucose could also be termed an aldohexose and fructose a ketohexose, whereas ribose would be an aldopentose, names which indicate both the number of carbons and the nature of the carbonyl group. Another aspeet of nomenclature is the use of the suffix -ulose to indicate a ketose. Fructose could thus be referred to as a hexulose, though we are more likely to see this suffix in the names of specific sugars, e.g. ribulose is a ketose isomer of the aldose ribose. 

A carbohydrate contains many V f hydroxyl groups and either an aldehyde or ketone functional group. A simple carbohydrate (monosaccharide or sugar) is an aldose if it contains an aldehyde group, or a ketose if it contains a ketone group. 

Generally useful reagent with a high silyl donor ability will not react with amino groups will not cause formation of enol-ether on unprotected ketone groups especially useful for ecdysones, norepinephrine, dopamine, steroids, sugars, sugar phosphates, and ketose isomers... 

A monosaccharide has the general formula (CH20) and contains either an aldehyde group (an aldose) or a ketone group (a ketose). The free aldehyde or ketone group can reduce cupric ions (Cu2+) to cuprous ions (Cu+) and hence such a monosaccharide is called a reducing sugar. 

Ketoses sugars containing one ketone group per molecule. 

As we have seen, sugars with aldehyde groups are called aldoses, and those with ketone groups are called ketoses. The number of carbon atoms in the sugar generally ranges from three to seven, designated by the terms triose (three carbons), tetrose (four carbons), pentose (five carbons), hexose (six carbons), and heptose (seven carbons). 

All carbohydrates have an aldehyde (aldose) or ketone (ketose) functional group (containing C=0) and a hydroxyl group (-OH). 

The structural formula of glucose contains a ring having six atoms (C5O, pyranose form) and an aldehyde group (aldoses). However, the structural formula of fructose contains a ring containing five atoms (C4O, furanose form) and a ketone group (ketoses) ... 

Osones.—We are not yet done with the interesting reactions of these compounds for the osazones when warmed with concentrated hydrochloric acid, take up water and split off the two phenyl hydrazine residues and yield a compound containing both the aldehyde and the ketone groups of the original aldose and ketose sugars. The resulting compound is known as an osone. 

Ketose A monosaccharide that contains a ketone group. 

Monosaccharides (also known as simple sugars) form the building blocks of carbohydrates. The empirical formula for simple sugars is CH2O. The name carbohydrate is derived from "hydrate of carbon" based on this formula. The names of monosaccharides use the suffix -ose. A monosaccharide contains multiple hydroxyl groups and may be an aldose or a ketose depending on whether it contains an aldehyde or a ketone group. 

Sugars which contain the aldehyde group —CHO are aldoses, those which contain the ketone group —CO are ketoses. If the formula for glyceraldehyde is drawn more fully, it can be seen, however, that it hides a further complexity. Two possible structures for glyceraldehyde can be drawn, which differ from one another in no other respect but that one is the mirror image of the other. These structures are isomers (see page 24) ... 

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