W-glycoside

Deoxy-sugars. Part XII. Experiments with the O- and W-Glycosides of Some Deoxy-sugars, K. Butler, S. Laland, W. G. Overend, and M. Stacey, J. Chem. Soc., (1950) 1433-1439. 

Figure 35-1. A segment of one strand of a DNA molecule in which the purine and pyrimidine bases guanine (G), cytosine (C), thymine (T), and adenine (A) are held together by a phosphodiester backbone between 2 -de-oxyribosyl moieties attached to the nucleobases by an W-glycosidic bond. Note that the backbone has a polarity (ie,a direction). Convention dictates that a single-stranded DNA sequence is written in the 5 to 3 direction (ie, pGpCpTpA, where G, C,T, and A represent the four bases and p represents the interconnecting phosphates).

T. Yoshioka, H. Yamada, and T. Uematsu, Glycosides of W-hydroxy-V-arylamine derivatives. Part 2. Convenient synthetic methods for W-glycosides of W-hydroxy-V-arylamines, J. Chem. Soc., Perkin Trans. I, (1985) 1271-1276. 

Schmidt, R R, Klotz, W, Glycoside bond formation via anomeric O-alkylation how many protective groups are required , Synlett, 168-170, 1991. 

The most important W-glycosides are, of course, the nucleotides and we have already described them in some detail. 

The concept of the anomeric effect in systems O-C-N is of great importance in chemical behavior of nucleosides, nucleotides, and nucleic acids since it controls the conformation of ribofuranosyl (or deoxyribofuranosyl) ring and with it the reactivity of the W-glycosidic bond. 

Structural formulas of the five most important purine and pyrimidine bases found in DNA and RNA.The hydrogen atom shown in color is lost in the formation of an W-glycoside. 

Nucleoside A building block of nucleic acids, consisting of D-ribose or 2-deoxy-D-ribose bonded to a heterocycUc aromatic amine base by a /3-W-glycosidic bond. 

The activation energy of the depurination of 19H was found to be 10 kcal/ mol by an Arrhenius plot, about 20kcal/mol lower than those (31-34 kcal/ mol) [79-81] of the depurination of DNAs in vitro and of hydrolysis of pyrimidines of deoxyribonucleosides. Due to the crowded environment around the hypoxanthine groups, the ground state potential energy of the W-glycosidic bond in the polymer was elevated more than that of the transition state, and thus the activation energy for the reaction decreased and the hydrolysis accelerated. 

Definition Water soluble high m.w. glycosidal substances occurring naturally in plants forms colloidal sol ns. on shaking with water Properties Tan, very fine powd. pungent disagreeable odor bitter taste sol, in water... 

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