P-Glycosidic bond

Suciose [57-50-1] (P-D-fructofuianosyl-a-D-glucopyianoside), 0 2 22, fomiula weight 342.3, is a disaccharide composed of glucose and fmctose residues joined by an a,P-glycosidic bond (Fig. 1). 

Most nucleosides contain D-ribose or 2-deoxy-D-ribose linked to N-1 of a pyrimidine or to N-9 of a purine by a P-glycosidic bond whose syn conformers predominate. 

Acetonitrile is another participating solvent, which in many cases leads to the formation of an equatorially linked glycoside [125-131], It has been proposed that these reactions proceed via an a-nitrilium ion intermediate. It is not well understood why the nitrilium ion adopts an axial orientation however, spectroscopic studies support the proposed anomeric configuration [130,131], It is known that nucleophilic substitution of the a-nitrilium ion by an alcohol leads to P-glycosidic bonds and the best P-selectivities are obtained when reactive alcohols at low reaction temperatures are employed. Unfortunately, mannosides give poor anomeric selec-tivities under these conditions. 

Lactose ( milk sugar, 2) is the most important carbohydrate in the milk of mammals. Cow s milk contains 4.5% lactose, while human milk contains up to 7.5%. In lactose, the anomeric OH group of galactose forms a p-glycosidic bond with C-4 of a glucose. The lactose molecule is consequently elongated, and both of its pyran rings lie in the same plane. 

Pyranmycin which contains both D-pyranose and L-pyranose at ring III, has been synthesized (Scheme 4.16). The p-glycosidic bond between rings II and... 

A band close to 880 cm-1, can be attributed to a P-glycosidic bond. Another band in the region of 846 cm-1 could indicate the presence of an a type involving galactose and/or mannose units. The principles of the method proposed by Barker et al. (11) proved to be a useful tool for the interpretation of IR spectra obtained from EPS from Rhizobium sp. EQ1. 

Which of the following polysaccharides contains p-glycosidic bonds ... 

Cellulose can be hydrolyzed to glucose by cleaving all of the p-glycosidic bonds, yielding both anomers of glucose. 

Both starch and cellulose are polymers of glucose, but starch contains a glycoside bonds, whereas cellulose contains P glycoside bonds. The two common forms of starch are amylose and amylopectin. 

Stevia and stevioside are absolutely safe for diabetics since it is used in minute amounts. Neither stevioside is taken up by our body, nor, due to the P-glycosidic bonds, is stevioside metabolised by the digestive enzymes... 

There are hyaluronidases that function as endo-(3-glucuronidases that cleave the (1 3)-P glycosidic bonds. However, no sequence data on these enzymes is yet available. These enzymes are characteristic of annelids such as leeches e.g., Herudo medicinalis [196-198], and certain crustaceans [199]. They utilize the hydrolysis mechanism, and thus resemble the vertebrate enzymes more closely than the prokaryotic hyaluronidases. 

The chemical composition of DNA, a long chained biopolymer, consists of a 2 -deoxyribose phosphate backbone with the four bases, namely adenine and guanine, the two purines, and thymine and cytosine, the two pyrimidines, attached through the C(l) position of the 2 -deoxyribose group by a P-glycosidic bond. The primary structure of one of the strands of DNA is shown in Figure 1. In its biological form DNA is double stranded and the two strands... 

P-Glycosidic bond between 2 -deoxyribose and each base... 

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