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An effective, practical, large-scale adaptable procedure has been developed to selectively dehydrate the fructose portion of isomaltulose (glucosyl-a( 1-+6)-fructose] (6): heating in DMSO in the presence of a strongly acidic ion-exchange resin generates a-D-glucosyloxymethylfurfural ("a-GMF" , 3), isolable in yields up to 70%. A variety of ensuing reactions have been exploited concerning the generation of products with industrial application profiles such as aldol-type additions to the dicyanovinyl (16), nitrovinyl (20), and benzoylvinyl (21) derivatives, or to the polymerizable unsubstituted vinyl compound (25) and the GMF-acrylic acid (22). Oxidation to GMF-carboxylic acid (1 1) and reductive amination to GMF-amine 8 can be carried out without affecting the hydroxyl groups in the glucosyl portion; esterification of 11 with long-chain alcohols and N-acylation of 8 with fatty acid chlorides provide novel surfactants in which hydrophilic and hydrophobic parts of the molecule are separated by a heteroaromatic spacer.5-Hydroxymethylfurfural (HMF, l), readily generated from fructose by acid-induced dehydrationL21, has been designated as one of the few "petrochemicals" accessible from regrowing and a key substance between carbohydrate chemistry and mineral oil-based industrial organic Despite the fact, however, that the technology for its pilot plant-size manufacture has been elaborated[2,4,51, it is not produced on an industrial scale for several obvious reasons: its chemistry is not fully developed with respect to products with industrial application profiles, and, more aggravatingly, raw materials from petrochemical sources are still more economical.Glycosylated hydroxymethylfurfurals of type 2-5, if accessible economically on a large scale, would substantially broaden the scope of HMF applications: carbonyl olefination and polymerization yield hydrophilic polymers, attachmet of long-chain alkyl residues via the respective furoic acid, for example, leads to novel APGs (alkylpolyglycosides), i.e. biodegradable surfactants in which the hydrophilic sugar moiety and hydrophobic alkyl portion of the molecule are separated by a heteroaromatic spacer.

The article contains sections titled: 1. Polyols, General 1.1. Definition 1.2. Physical, Chemical, and Organoleptic Properties 1.3. Metabolism and Nutrition 1.3.1. Uptake, Digestion, and Tolerance 1.3.2. Nutritional Aspects 1.3.3. Oral Health and Hygiene 1.3.4. Oxidative Stress 1.3.5. Conclusion 1.4. Regulatory Aspects 2. Xylitol 2.1. Physical, Chemical, and Organoleptic Properties 2.2. Production 2.3. Specifications, Analysis, and Legal Aspects 2.4. Uses 2.5. Metabolism, Tolerance, and Safety 3. Sorbitol 3.1. Physical, Chemical, and Organoleptic Properties 3.2. Production 3.3. Regulatory and Quality Aspects 3.3.1. Purity Requirements 3.3.2. Analysis 3.4. Uses 3.5. Physiology, Tolerance, Toxicology 3.6. Economic Aspects 4. Mannitol 4.1. Physical, Chemical, and Organoleptic Properties 4.2. Production 4.3. Quality Aspects 4.4. Uses 4.5. Physiology, Tolerance, Toxicology 5. Isomaltulose and Trehalulose, Isomalt 5.1. Isomaltulose and Trehalulose 5.1.2. Physical and Chemical Properties 5.1.3. Production 5.1.4. Uses 5.1.5. Economic Aspects 5.2. Isomalt 5.2.1. Physical and Chemical Properties 5.2.2. Production 5.2.3. Uses 5.2.4. Economic Aspects 6. Lactitol 6.1. Physical, Chemical, and Physiological Properties 6.2. Production 6.3. Analysis and Regulatory Status 6.4. Uses 6.5. Economic Aspects 7. Maltitol and Maltitol‐Containing Syrups 7.1. Physical, Chemical, and Organoleptic Properties 7.2. Uses 7.3. Economic Aspects 8. Erythritol 8.1. Physical, Chemical, and Physiological Properties 8.2. Production 8.3. Analysis and Regulatory Status 8.4. Uses 8.5. Economic Aspects

In [D,]DMSO the anomeric 2-OH groups of furanoid and pyranoid tautomers O f D-fIUtOSe give distinct. clearly separated singlets, their intensities providing an exact measure of the tautomeric distribution and allowing its determination as a function of temperature and time. Equilibration of tautomers in DMSO being exceedingly slow, this OH-NMR methodology can be applied to detcrmine tautomeric ratios in other solvents, too, by freezing a sample (liquid Nz), dissolution of the resulting ice-matrix in DMSO and rapid recording of the intensities in the low-field OH-region. 'The data obtaincd in this way for aqueous solutions at equilibrium between 0 and 8O'C correlate well with "C NMR-derived values yet are more consistent and considerably more easy to obtain; they cxhibit a clearly linear relationship between equilibrium composition and temperature such that the two fructofuranoses and the a-p-tautomcr increase with temperature on expense of the P-p-form, which at 80°C comprises 550/. at 110°C (i. e. in thc molten state) only 45"h of the tautomers. In pyridinc, the cquilibrium distribution shows a similar linear temperature dependence as does the ratc of equilibration, being nearly nondetectable at 0°C versus essentially instantaneous adaption above 6 0 T , thereby explaining the different outcome of fructose derivatizations in pyridine. (0 VCH Verlagsgesellschaft mbH, D Untersuchungen an

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