Abstract
Glycoside hydrolyses are important bioorganic processes whose mechanisms are of considerable interest to physical organic chemists. A simple glycoside may undergo nucleophilic substitution in three ways.(i) The stepwise SNI mechanism involves ratedetermining heterolysis of the bond to the aglycone leaving group, forming a glycosyl cation which is then subject to nucleophilic attack.(ii) The concerted SN2 mechanism involves a bond to the nucleophile being formed as the bond to the leaving group is broken.(iii) The stepwise pre-association mechanism is similar to SNI except that the nucleophile is present in the rate determining step as a" spectator".
The approximate lifetime of typical glycosyl oxocarbenium ions is 10-12s, and experiment suggests that glycoside hydrolysis occurs s 1, 2 at the borderline of the SNI and SN2 mechanism. Characterization of these processes requires knowledge of the transition …
The approximate lifetime of typical glycosyl oxocarbenium ions is 10-12s, and experiment suggests that glycoside hydrolysis occurs s 1, 2 at the borderline of the SNI and SN2 mechanism. Characterization of these processes requires knowledge of the transition …
Original language | English |
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Pages (from-to) | 134-139 |
Number of pages | 6 |
Journal | AIP Conference Proceedings |
Volume | 330 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1995 |