Carbohydrate Chemistry A Review of the Literature Published During 1981. Macromolecules

Excerpt. © Reprinted by permission. All rights reserved. Carbohydrate Chemistry Volume 15Mono-, Di-, and Tri-saccharides and Their DerivativesBy N. R. WilliamsThe Royal Society of ChemistryCopyright © 1983 The Royal Society of ChemistryAll rights reserved.ISBN: 978-0-85186-152-4Contents1 Introduction, 3, 2 Free Sugars, 5, 3 Glycosides, 18, 4 Ethers and Anhydro-sugars, 50, 5 Acetals, 60, 6 Esters, 67, 7 Halogeno-sugars, 84, 8 Amino-sugars, 91, 9 Miscellaneous Nitrogen Derivatives, 106, 10 Thio- and Seleno-sugars, 117, 11 Deoxy-sugars, 124, 12 Unsaturated Derivatives, 129, 13 Branched-chain Sugars, 139, 14 Aldosuloses, Dialdoses, and Diuloses, 146, 15 Sugar Acids and Lactones, 150, 16 Inorganic Derivatives, 160, 17 Alditols and Cyclitols, 166, 18 Antibiotics, 176, 19 Nucleosides, 198, 20 N.m.r. Spectroscopy and Conformational Features, 222, 21 Other Physical Methods, 231, 22 Separatory and Analytical Methods Chromatographic Methods, 243, 23 Synthesis of Enantiomerically Pure Non-carbohydrate, 251, Author Index, 263, CHAPTER 1IntroductionAlthough the two parts of this report are now being published separately , the general format and coverage of this section, covering the organic chemistry of mono-, di-, and tri-saccharides, has not been changed. It might be helpful to point out firstly that a hard and fast division has not been drawn between trisaccharides and higher oligosaccharides, particularly in the chapters dealing with glycosides and antibiotics, and secondly that the coverage on glycosides, antibiotics, nucleosides and related compounds containing carbohydrate units is selective for those papers where there is judged to be some specific carbohydrate interest besides any for the aglycone components; in the fringe areas, we hope this principle is acceptable in the interests of keeping the report within reasonable, economic limits.The trends in research endeavour noted in recent reports have been continued, and the extensive sections on glycoside synthesis, antibiotics and nucleosides reflect the major interest in these areas. The synthesis of tri- and higher oligosaccharides is fast becoming a routine procedure for providing substrates of immunochemical interest. New antibiotic materials continue to be discovered consisting mainly or entirely of carbohydrate components in complex structures, and a ever widening variety of nucleoside analogues have been reported. These areas pose problems in classification, and we hope the distinctions that have been drawn between nucleosides on the one hand and miscellaneous nitrogen compounds on the other have not been too arbitrary for general acceptance. Another growth area has been the application of carbohydrates as chiral templates for the synthesis of a wide range of naturally occurring chiral compounds. Chapters 20 and 21 reflect the fruitful application of both routine and newer developments in spectroscopic techniques for the analysis of carbohydrate compounds and illustrate how much can be learned about relatively complex materials without actually doing any chemistry on them.Recommendations for the nomenclature of unsaturated and branched-chain sugars, and of conformations of five and six-membered rings have been published during the year.CHAPTER 2Free SugarsThe main pathways of reaction of primary free radicals in carbohydrates have been reviewed. A review on the use of sugars in fermentation and for preparation of sweeteners, plastics and chemicals has appeared.The tastes of chlorinated derivatives of simple monosaccharides have been compared with those of the parent sugars and the di-saccharides maltose and trehalose in relation to existing theories of the sweetness sensation.Isolation and SynthesisThe isolation by gel chromatography of D-threo-pent-2-ulose from the lipopolysaccharide of Pseudomonas diminuta NCTC 8545 represents the first time this sugar has been observed in a microbial polymer.Two reviews of the formose reaction by the same authors have appeared, and i