Glucose Fischer projections

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 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... 

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. 

Monosaccharide structures may be depicted in open-chain forms showing their carbonyl character, or in cyclic hemiacetal or hemiketal forms. Alongside the Fischer projections of glucose, ribose, and fructose shown earlier, we included an alternative... 

Fig. 1. Higher-order sugars L-g/yceroD-manno-Heptose (1, open-chain and 2, a-pyranose) and A -acetylneurami ilic acid (3, a-pyranose form). Structures 4-8 depict D-glucose (4) as its open-chain Fischer projection, and as the a-oxetose (5), a-furanose (6), a-pyranose (7), and a-septanose (8) ring forms.

FIGURE 7-7 Pyranoses and furanoses. The pyranose forms of o-glucose and the furanose forms of o-fructose are shown here as Haworth perspective formulas. The edges of the ring nearest the reader are represented by bold lines. Hydroxyl groups below the plane of the ring in these Haworth perspectives would appear at the right side of a Fischer projection (compare with Fig. 7-6). Pyran and furan are shown for comparison. 

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