492-93-3Relevant articles and documents
Synthesis of a carbohydrate-centered C-glycoside cluster
Dubber, Michael,Lindhorst, Thisbe K.
, p. 755 - 760 (2001)
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Controlling Sugar Deoxygenation Products from Biomass by Choice of Fluoroarylborane Catalyst
Seo, Youngran,Lowe, Jared M.,Gagné, Michel R.
, p. 6648 - 6652 (2019/08/26)
The feedstocks from biomass are defined and limited by nature, but through the choice of catalyst, one may change the deoxygenation outcome. We report divergent but selective deoxygenation of sugars with triethylsilane (TESH) and two fluoroarylborane catalysts, B(C6F5)3 and B(3,5-CF3)2C6H3)3 (BAr3,5-CF3). To illustrate, persilylated 2-deoxyglucose shows exocyclic C-O bond cleavage/reduction with the less sterically congested BAr3,5-CF3, whereas endocyclic C-O bond cleavage/reduction predominates with the more Lewis acidic B(C6F5)3. Chiral furans and linear polyols can be selectively synthesized depending on the catalysts. Mechanistic studies demonstrate that the resting states of these catalysts are different.
Total Synthesis of Neodysiherbaine A via 1,3-Dipolar Cycloaddition of a Chiral Nitrone Template
Hirai, Toshihiro,Shibata, Kohki,Niwano, Yohei,Shiozaki, Masao,Hashimoto, Yoshimitsu,Morita, Nobuyoshi,Ban, Shintaro,Tamura, Osamu
supporting information, p. 6320 - 6323 (2017/12/08)
The total synthesis of neodysiherbaine A was achieved via 1,3-dipolar cycloaddition of a chiral nitrone template with a sugar-derived allyl alcohol in the presence of MgBr2·OEt2. This cycloaddition constructed the C2 and C4 asymmetric centers in a single step. Then reductive cleavage, intramolecular SN2 reaction of the tertiary alcohol, and oxidation of the primary alcohol afforded neodysiherbaine A.
A biophysical study with carbohydrate derivatives explains the molecular basis of monosaccharide selectivity of the Pseudomonas aeruginosa lectin lecB
Sommer, Roman,Exner, Thomas E.,Titz, Alexer
, (2015/02/19)
The rise of resistances against antibiotics in bacteria is a major threat for public health and demands the development of novel antibacterial therapies. Infections with Pseudomonas aeruginosa are a severe problem for hospitalized patients and for patients suffering from cystic fibrosis. These bacteria can form biofilms and thereby increase their resistance towards antibiotics. The bacterial lectin LecB was shown to be necessary for biofilm formation and the inhibition with its carbohydrate ligands resulted in reduced amounts of biofilm. The natural ligands for LecB are glycosides of D-mannose and L-fucose, the latter displaying an unusual strong affinity. Interestingly, although mannosides are much weaker ligands for LecB, they do form an additional hydrogen bond with the protein in the crystal structure. To analyze the individual contributions of the methyl group in fucosides and the hydroxymethyl group in mannosides to the binding, we designed and synthesized derivatives of these saccharides.We report glycomimetic inhibitors that dissect the individual interactions of their saccharide precursors with LecB and give insight into the biophysics of binding by LecB. Furthermore, theoretical calculations supported by experimental thermodynamic data suggest a perturbed hydrogen bonding network for mannose derivatives as molecular basis for the selectivity of LecB for fucosides. Knowledge gained on the mode of interaction of LecB with its ligands at ambient conditions will be useful for future drug design.
