Fischer glucose

Fischer determined the struc ture of glucose in 1900 and won the Nobel Prize in chemistry in 1902... 

Of all the monosaccharides d (+) glucose is the best known most important and most abundant Its formation from carbon dioxide water and sunlight is the central theme of photosynthesis Carbohydrate formation by photosynthesis is estimated to be on the order of 10 tons per year a source of stored energy utilized directly or indi rectly by all higher forms of life on the planet Glucose was isolated from raisins m 1747 and by hydrolysis of starch m 1811 Its structure was determined in work culmi nating m 1900 by Emil Fischer... 

Once the eight Fischer projections have been written they are named m order with the aid of the sentence All altruists gladly make gum m gallon tanks The words of the sentence stand for allose altrose glucose mannose gulose idose galactose talose... 

The classical approach to structure determination in carbohydrate chemistry is best exemplified by Fischer s work with D glucose A detailed account of this study appears in the August 1941 issue of the Journal of Chemical Education (pp 353-357)... 

The aldohexoses are allose, altrose, glucose, mannose, gulose, idose, galactose, and talose. The mnemonic All altruists gladly make gum in gallon tanks is helpful in writing the conect Fischer projection for each one. 

Carbohydrates with more than one chirality center are shown in. Fischer projections by stacking the centers on top of one another. By convention, the carbony] carbon is always placed either at or near the top. Glucose, for... 

Fischer s original method for conversion of the nitrile into an aldehyde involved hydrolysis to a carboxylic acid, ring closure to a cyclic ester (lactone), and subsequent reduction. A modern improvement is to reduce the nitrile over a palladium catalyst, yielding an imine intermediate that is hydrolyzed to an aldehyde. Note that the cyanohydrin is formed as a mixture of stereoisomers at the new chirality center, so two new aldoses, differing only in their stereochemistry at C2, Tesult from Kiliani-Fischer synthesis. Chain extension of D-arabinose, for example, yields a mixture of D-glucose and o-mannose. 

Conventional representation of a carbon atom (e.g. C-2 of D-glucose) in the Fischer projection. Representation (e) will be used in general in the present document. 

The formula below is the Fischer projection for the acyclic form of D-glucose. The Fischer projections of the other aldoses (in the acyclic form) are given in Chart I (2-Carb-2.2)., ... 

The following schematic representation of pyranose ring closure in D-glucose shows the reorientation at C-5 necessary to allow ring formation this process corresponds to the change from Fischer to modified Fischer projection. 

It is to be noticed that although the anhydro ring of levoglucosan is stable to alkali (Tanret s preparative method consisted in the heating of aromatic jS-D-glucosides with aqueous alkali), it readily undergoes scission in the presence of acid. An isomeric glucose anhydride prepared in 1912 by E. Fischer showed, however, very different properties. 

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