Sugar conformations diagrams

The most important sugar is glucose. It has a saturated six-membered ring containing oxygen and it is best drawn in a chair conformation with nearly all the substituents equatorial. It can also be drawn reasonably as a flat configurational diagram. 

Illustrations with organic structural formulae have been used widely. In depicting sugar rings. Mills formulae have been used if the conformation is not known with confidence, otherwise conformational structures are drawn. Ribbon diagrams of various carbohydrate-active proteins with known structures are available from protein databases. Their reproduction in this book would have increased its cost and, at a time when all beginning researchers have Web access, only marginally increased its usefulness. If the reader wants to know what, say, a GH6 cellulase looks like, he or she should go to CAZy, the wonderful resource for the whole scientific community started by Bernard Henrissat and maintained by him and Pedro Coutinho, and click on the links in the 3D column. The protein can then be viewed in various downloadable viewers. 

Fig. 2.—Potential-energy Diagram (Somewhat Idealized) for a Monocyclic Pyranoid Sugar as a Function of the Conformation.

A symposium report has been published on the conformational properties of deo genated sugars, with emphasis on furanose derivatives. A review with 18 references is concerned with certain stereochemical problems associated with small carbohydrate molecules and aims to show how the combination of experimental n.m.r. studies and theoretical computer simulation can be brought to bear on their resolution. In connection with the total synthesis of palytoxin, a review has been written covering the conformational anal is of O-and C-disaccharides and presents a useful mode (diamond lattice diagrams) for predicting the solution conformations of these compounds. A further review deals with C-n.m.r. studies, especially by use of relaxation probes, of the interaction between metal ions and carbohydrates. ... 

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