56632-56-5Relevant articles and documents
Metal-free glycosylation with glycosyl fluorides in liquid SO2
Gulbe, Krista,Lugi?ina, Jevge?ija,Jansons, Edijs,Kinens, Artis,Turks, Māris
supporting information, p. 964 - 976 (2021/05/05)
Liquid SO2 is a polar solvent that dissolves both covalent and ionic compounds. Sulfur dioxide possesses also Lewis acid properties, including the ability to covalently bind Lewis basic fluoride ions in a relatively stable fluorosulfite anion (FSO2?). Herein we report the application of liquid SO2 as a promoting solvent for glycosylation with glycosyl fluorides without any external additive. By using various temperature regimes, the method is applied for both armed and disarmed glucose and mannose-derived glycosyl fluorides in moderate to excellent yields. A series of pivaloyl-protected O- and S-mannosides, as well as one example of a C-mannoside, are synthesized to demonstrate the scope of the glycosyl acceptors. The formation of the fluorosulfite species during the glycosylation with glycosyl fluorides in liquid SO2 is proved by 19F NMR spectroscopy. A sulfur dioxide-assisted glycosylation mechanism that proceeds via solvent separated ion pairs is proposed, whereas the observed α,β-selectivity is substrate-controlled and depends on the thermodynamic equilibrium.
Photo-induced glycosylation using a diaryldisulfide as an organo-Lewis photoacid catalyst
Iibuchi, Naoto,Eto, Takahiro,Aoyagi, Manabu,Kurinami, Reiji,Sakai, Hayato,Hasobe, Taku,Takahashi, Daisuke,Toshima, Kazunobu
supporting information, p. 851 - 855 (2020/02/15)
Photo-induced glycosylations of several acceptors with trichloroacetimidate donors using bis(2-naphthyl)disulfide as an organo-Lewis photoacid (LPA) catalyst proceeded effectively to give the corresponding glycosides in good to high yields. In addition, t
Visible light promoted method for constructing O-glycoside bonds
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Paragraph 0027-0029, (2020/07/13)
The invention discloses a visible light promoted method for constructing O-glycoside bonds. Glycosyl trichloroacetimidate is taken as a donor, and phenolic compounds are taken as a photocatalyst; a molecular sieve is added; and the O-glycoside bonds are g