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Alkyl glucosides/glycosides

Acylations of carbohydrate derivatives such as alkyl glucosides and galactosides have also been successfully performed in ionic liquids [63]. Similarly, the flavonoid glycosides naringin and rutin were acylated with vinyl butyrate in ionic liquid media in the presence of a number of lipases, e.g., CaLB (Novozym 435), immobilized TIL, and RmL [119]. The products are of interest for application as strong antioxidants in hydrophobic media. [Pg.238]

Commercial alkyl glycosides or, more specifically, alkyl glucosides are complex mixtures of acetals. Acetals, in general, are formed by the reaction of aldehydes and alcohols in the presence of a strong acid catalyst. The reaction involves an intermediate known as a hemiacetal. When acetaldehyde is dissolved in an excess of anhydrous ethyl alcohol in the presence of anhydrous hydrogen chloride, the following reactions occur ... [Pg.71]

The commercial production of alkyl glycosides is primarily the production of alkyl glucosides from a primary alcohol or primary alcohol mixture containing about 8-18 carbon atoms and a glucose source. Two of the most common processes for the reaction of an alcohol or alcohol mixture and a glucose source are described as follows ... [Pg.77]

The use of thiogtycosides in glycoside synthesis is referred to in a later section of this Chapter a novel development involves anodically oxidising the sulphur atom of 5-aryl 1-thio-O-glucopyranosides in the presence of alcohols to obtain alkyl glucosides (poor anomeric selectivity) together with diaryl disulphides. Mainly -products were obtained when the peracetylated thioglycosides were used. ... [Pg.18]

The first alkyl glucoside was synthesized and identified in the laboratory by Emil Fischer in 1893 [1], This process is now well known as the Fischer glycosida-tion and comprises an acid-catalyzed reaction of glycoses with alcohols. The structure of ethyl glucoside was defined correctly by Fischer, as may be seen from the historical furanosidic formula proposed ( Fischer projection ). In fact, Fischer glycosidation products are complex, mostly equilibrium mixtures of a/p-anomers and pyranoside/furanoside isomers which also comprise randomly linked glycoside oligomers (Fig. 1) [2]. [Pg.1]

An observed effect of certain substituents on the conformation and stability of glycosides. In the case of a- and /3-glucosides, when the substituent attached to the anom-eric position of o-glucose is a nonpolar alkyl group, such a substituent will favor the equatorial position /3). However, if the substituent is polar, the a-position i.e., axial) is favored. Thus with polar moieties, a-glucosides exhibit greater stability than /3-glucosides. [Pg.59]


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See also in sourсe #XX -- [ Pg.69 , Pg.70 , Pg.71 , Pg.72 , Pg.73 , Pg.74 , Pg.75 , Pg.76 , Pg.77 , Pg.78 , Pg.79 , Pg.80 ]




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Alkyl glucoside

Alkyl glucosides/glycosides acetals

Alkyl glucosides/glycosides alcohols

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