Glycosides bond cleavage

Fig. 8. Glycosidic bond cleavage by neuraminidase passes through a cationic intermediate with planar geometry about C2. Reprinted with permission from Chong el al. (1992).

Cabiaca A, Guillona E, Chambonb F, Knel C, Rataboulb F, Essayem N. Cellulose reactivity and glycosidic bond cleavage in aqueous phase by catalytic and non catalytic transformations. Appl Catal A Gen 2011 402 1-10. 

Zheng Y, Cloutier P, Hunting DJ, Wagner JR, Sanche L (2006). Phosphodiester and N-glycosidic bond cleavage in DNA induced by 4-15 eV electrons. J Chem Phys 124 064710-064719. 

Gu J, Xie Y, Schaefer HF (2005). Glycosidic bond cleavage of pyrimidine nucleosides by low energy electrons A theoretical rationale. J Am Chem Soc 127 1053-1057. 

The same conditions result in glycosidic bond cleavage when 8-bromo-2 -deoxynucleosidc is used. However, when sodium hydrosulfide is employed, the desired 2 -deoxy-8-sulfanylnu-deoside is readily obtained, e.g. formation of 12. ... 

Fpg recognition mode of FapyG residue and mechanism of catalyzing N-glycosidic bond cleavage... 

FucT This apparently contradictory scenario has in fact arisen in many other GT-B glycosyltransferases with the conclusion being that the metal cofactor simply facilitates the departure of the phosphate leaving group from the active site, but is not directly involved in the glycosidic bond cleavage step. 

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