Glucose, anhydrosugars

Glucose, galactose, xylose and arabinose give rise to the formation of the corresponding anhydrosugars. 

Anhydrosugars are an important class of compounds in which the three-membered oxirane ring is connected to the anomeric and the C-2 atoms of a sugar. The first compound of this class, the so-called Brigl s anhydride (26), was prepared by treatment of 8-chloro-3,4,6-tri-0-acetyl-D-glucose (25) with ammonia ( Scheme 11) [3]. 

Polyester fibers are composed of linear chains of polyethylene terephthalate (PET), which produces benzene, benzoic acid, biphenyl, and vinyl terephthalate on pyrolysis. Acrylic fibers comprise chains made up of acrylonitrile units, usually copolymerized with less than 15% by weight of other monomers, e.g., methyl acrylate, methyl methacrylate, or vinylpyrrolidone. Thermolysis results in the formation of acrylonitrile monomer, dimers, and trimers with a small amount of the copolymer or its pyrolysis product. In this case, the acrylic is Orion 28, which contains methyl vinyl pyridine as comonomer. Residual dimethyl formamide solvent from the manufacturing process is also found in the pyrolysis products. Cotton, which is almost pure cellulose, comprises chains of glucose units. The pyrolysis products of cellulose, identified by GC/MS, include carbonyl compounds, acids, methyl esters, furans, pyrans, anhydrosugars, and hydrocarbons. The major pyrolysis products are levoglucosan (1,6-anhydro-B-D-glucopyranose) and substituted furans. 

Figure 3.214 Isocratic separation of sugar alcohols, anhydrosugars, and glucose. Separator columns Metrosep A Supp 15-1- Metrosep Carb 1 column dimensions 150 mm x 4 mm I. d. (Metrosep A Supp 15) and 250 mm x4 mm i.d. (Metrosep Carb 1) column temperatures ...

A new route to 1,2-tronr-glycosyl thiocyanates, such as the glucose derivative 5, involved opening of 1,2-anhydrosugars with ammonium thiocyanate and phase transfer catalyzed reaction of glycosyl halides with < -ethyl-S potassium dithiocarbonate proved to be an efficient new method for the preparation of the known 5-glycosyl xanthates 6. ... 

The 3-C-hydroxymethyl derivatives of D-xylose, L-lyxose, D-ribose and D-glucose have each been shown to be in equilibrium with a new type of anhydrosugar-l,3 -anhydro-3-C-hydroxymethylaldoses, e.g. (27). ... 

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