459170-36-6Relevant academic research and scientific papers
Zwitterionic Polysaccharides of Shigella sonnei: Synthetic Study toward a Ready-for-Oligomerization Building Block Made of Two Rare Amino Sugars
Pfister, Hélène B.,Paoletti, Julie,Poveda, Ana,Jimenez-Barbero, Jesus,Mulard, Laurence A.
, p. 4270 - 4282 (2018/11/23)
Shigellosis is an endemic diarrheal disease caused by Gram negative bacteria named Shigella. The most exposed polysaccharides of Shigella sonnei display a zwitterionic disaccharide repeating unit (AB) made of two rare amino sugars: [4)-α- l -Alt p NAcA-(1→3)-β- d -Fuc p NAc4N-(1→]. An original synthesis of a ready-for-oligomerization AB disaccharide is reported. The targeted orthogonally protected disaccharide was synthesized from l -glucose and tetra- O -acetyl-β- d -glucosamine. The challenging introduction of the 4 B -azido group masking the amino moiety of the AAT residue was performed at the disaccharide stage by a two-step procedure (triflation followed by nucleoaphilic displacement with NaN 3). A post-glycosylation oxidation strategy was employed to access the altruronate moiety.
Synthesis of 5-fluoro N-acetylglucosamine glycosides and pyrophosphates via epoxide fluoridolysis: Versatile reagents for the study of glycoconjugate biochemistry
Hartman, Matthew C. T.,Coward, James K.
, p. 10036 - 10053 (2007/10/03)
Numerous carbohydrate-processing enzymes facilitate catalysis via stabilization of positive charges on or near the C-1, C-4, C-5, or C-6 positions. Substrate analogues differing only in the substitution of a fluorine for the axial C-5 hydrogen would possess reduced electron density at these positions and could be useful mechanistic probes of these enzymes. Introduction of this 5-fluoro substituent after radical halogenation was problematic because of the incompatibility of many protecting groups to the radical halogenation and the instability of the subsequent 5-fluoro hexosamines. Thus, to allow easy access to a wide variety of 5-fluoro glycosides and glycosyl phosphates, a versatile method for the introduction of the 5-fluoro group has been developed, the key step being the fluoridolysis of C-5, 6 epoxides. By use of this method, two fluorinated carbohydrates, uridine 5′-diphospho-5-fluoro-N-acetylglucosamine and octyl 5-fluoro-N-acetylglucosamine, have been synthesized. Initial biochemical investigations of these compounds show that 5-fluoro analogues are useful probes of transition-state charge development in several enzyme-catalyzed reactions.
