Sugars and sugar derivatives

Note The reagent can be employed on sihca gel, kieselguhr. Si 50 000 and cellulose layers. At room temperature sugars and sugar derivatives react at different rates depending on the functional groups present [1], e.g. ketoses react more rapidly than aldoses. It is possible to differentiate substance types on this basis [1, 3]. 

The condensation reactions of aromatic o-diamines and sugars and sugar derivatives have been studied in detail and quinoxaline derivatives have been prepared recently from osones, osonehydrazones, and dehydro-L-ascorbic acidd ... 

TABLE 2.1 Annual Production Volume and Prices of Simple Sugars and Sugar-Derived Alcohols and Acids as Compared to Some Petrochemically Derived Basic Chemicals and Solvents... 

One of the diastereomers of sugars (and sugar derivatives) differing only in the configuration about the internal hemiacetal or hemiketal carbon (/.c., the so-called anomeric carbon). ... 

Figure 4-4 Some simple sugars and sugar derivatives in ring forms.

The specific optical rotation of many sugars and sugar derivatives is altered by the presence of metal salts, the alteration being the greater, the greater the concentration of the salt. This phenomenon, which is now generally attributed to the formation of adducts, will be considered later in more detail. 

Before discussing the various methods used to achieve condensation polymerization of sugars and sugar derivatives, several factors will be... 

FERMENTATION. A form of respiration that requires no oxy gen. There is an incomplete breakdown of lilod carbon dioxide and oilier products, such as alcohol, are formed. The vsord is commonly used to refer to the conversion of sugars (and sugars derived from starch) into ethyl alcohol by the enzymes of yeast. 

Examples of oxidative transformations for the synthesis of chemicals starting from sugars and sugars-derived compounds include the following (Figure 9.18) ... 

The names of simple sugars and sugar derivatives can all be abbreviated. This also allows an abbreviated description of the component sugars present in disaccharides, for example. 

The use of such tritylation methods may prove to be of importance with other sugars and sugar derivatives. 

Of the other partly acylated sugars and sugar derivatives, Pigman and Isbell s D-talose 1,2-orthobenzoic acid behaves in a similar manner to Ohle s benzoyl derivative. It is fairly stable toward acid but is unstable toward alkali. Apparently the alkalinity of pyridine and, perhaps, traces of alkalinity present in water and methyl alcohol are sufficient to produce irreversible changes that manifest themselves in the optical behavior of the respective solutions these changes in rotation have not been investigated further. 

Although the chemical modifications to sugars and sugar derivatives described in this chapter generally follow Sn2 mechanisms, special consideration must be given to the cyclic nature of most... 

SCHEME 6.32 The Mitsunobu reaction can dehver phthahmides to sugars and sugar derivatives. 

Anionic nucleophiles provide valuable and versatile routes for the preparation of C-glycosides. However, the most extensively used technologies lie within the chemistry of Lewis acid-mediated reactions of carbohydrates with unsaturated hydrocarbons and derivatives thereof. In the next series of examples, reactions of sugars and sugar derivatives with olefins and their silyl-, stannyl-, and aluminum derivatives are discussed. 

Figure 4 shows the results for sugars and sugar derivatives. The sorbitol, which lacks the hemiacetal and acetal groups of the sugars, shows weak chlorine release only during... 

III. Condensation of Alcohols and Phenols with Sugars and Sugar Derivatives.. 163... 

Mattiasson B, Rieke E, Munnecke D, Mosbach K (1979) Enzyme analysis of organophosphate insecticides using an enzyme thermistor. J Solid-Phase Biochem 4 263-270 Mattiasson B, Danielsson B, Hermansson C, Mosbach K (1977b) Enzyme thermistor analysis of heavy metal ions with use of immobilized urease. FEBS Lett 85 203-206 Mattiasson B, Danielsson B (1982) Calorimetric analysis of sugars and sugar derivatives with aid of an enzyme thermistor. Carbohydr Res 102 273-283 Mattiasson B, Danielsson B,Winquist F, Nilsson H, Mosbach K (1981) Enzyme thermistor analysis of penicillin in standard solutions and fermentation broth. Appl Environm Microbiol 41(4) pp 903-908... 

Decristoforo G and Danielsson B 1984 Flow injection analysis with enzyme thermistor detector for automated detection of -lactams Anal. Chem. 56 263-8 Danielsson B, Mattiasson B and Mosbach K 1981 Enzyme thermistor devices and their analytical applications Appl. Biochem. Bioeng. 3 97-143 Mattiasson B and Danielsson B 1982 Calorimetric analysis of sugars and sugar derivatives with aid of an enzyme thermistor Carbohydr. Res. 102 273-82 Kirstein D, Danielsson B, Scheller F and Mosbach K 1989 Highly sensitive enzyme thermistor determination of ADP and ATP by multiple recycling enzyme systems Biosensors 4 231-9... 

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