2873-29-2Relevant articles and documents
A new catalyst for the reductive elimination of acylated glycosyl bromides to form glycals
Stick, Robert V.,Stubbs, Keith A.,Tilbrook, D. Matthew G.,Watts, Andrew G.
, p. 83 - 85 (2002)
Ethylene-N,N′-bis(salicylideneiminato(IV)) {VO(salen)} was developed as a catalyst for the reductive elimination of acylated glycosyl bromides to form glycals. VO(salen) to be an effective catalyst for the preparation of glycals on a multi-gram scale. The catalyst was green in colour and changed to brown as the reaction progress.
Reactivity of per-O-acetylated 1-thioglycosides and glycosyl sulfones towards chromium(II) complexes in aqueous medium
Micskei, Károly,Juhász, Zsuzsa,Ratkovi?, Zoran R.,Somsák, László
, p. 6117 - 6120 (2006)
Anomeric carbon-sulfur bonds in 1-thioglycosides and glycosyl sulfones can be cleaved by chromium(II) complexes in water-DMF medium. Anomeric radicals as well as sugar-chromium(III) complex intermediates can be generated in these reactions, leading in some cases, to the exclusive formation of the corresponding glycals.
A convenient and efficient synthesis of glycals by zinc nanoparticles
Xu, Yun,Wang, Wenjun,Cai, Yu,Yang, Xia,Wang, Peng George,Zhao, Wei
, p. 46662 - 46665 (2014)
A simple and efficient method for the synthesis of pyranoid glycals utilizing the reductive elimination of glycopyranosyl bromides by zinc nanoparticles in an acetate buffer is described. A variety of pyranoid glycals derivatives were obtained, especially for the synthesis of 6-deoxy-4,6-O-benzylidene and disaccharide glycals with good yields.
A convenient synthesis of glycals employing in-situ generated Cp2TiCl
Hansen, Thomas,Krintel, Sussie L.,Daasbjerg, Kim,Skrydstrup, Troels
, p. 6087 - 6090 (1999)
Reductive elimination of acetylated glycosyl bromides to the corresponding glycal is easily achieved by mixing the bromide with Cp2TiCl2 and Mn in THF, and hence does not require the separate preparation of Cp2TiCl using glove-box techniques.
A room temperature Negishi cross-coupling approach to C-alkyl glycosides
Gong, Hegui,Sinisi, Riccardo,Gagne, Michel R.
, p. 1908 - 1909 (2007)
Glycosyl halides serve as effective alkyl halides for room temperature Negishi cross-coupling reactions using functionalized alkyl zinc reagents. The catalyst for these reactions is in situ generated (PyBox)NiCl2. The functional group tolerance on the zinc reagent is typically high, and both benzyl and ester protecting groups on the carbohydrate are tolerated. Anomer selectivities are modest for glucosyl halides but high for mannosyl halides. Copyright
Long-lived glycosyl-chromium(III) complex intermediates in aqueous medium. Preparation of pyranoid glycals
Kovacs, Gyoengyver,Gyarmati, Julianna,Somsak, Laszlo,Micskei, Karoly
, p. 1293 - 1296 (1996)
Acetylated glycosyl-chromium(III)L (L=EDTA, NTA, IDA) complex intermediates (1) were detected in aqueous medium, with half-life-times of 30-300 minutes. The decay of these intermediates led to glycals (7-9) of high purity in preparatively usable 70-90% yields.
Controlled Living Cascade Polymerization to Make Fully Degradable Sugar-Based Polymers from d -Glucose and d -Galactose
Bhaumik, Atanu,Peterson, Gregory I.,Kang, Cheol,Choi, Tae-Lim
, p. 12207 - 12211 (2019)
Monomers derived from glucose and galactose, which contain an endocyclic alkene (in the sugar ring) and a terminal alkyne, underwent a cascade polymerization to prepare new polymers with the ring-opened sugar incorporated into the polymer backbone. Polymerizations were well-controlled, as demonstrated by a linear increase in molecular weight with monomer-to-initiator ratio and generally narrow molecular weight dispersity values. The living nature of the polymerization was supported by the preparation of a block copolymer from two different sugar-based monomers. The resulting polymers were also fully degradable. They underwent fast and complete depolymerization to small molecules under acidic conditions.
Titanium(III) reagents in carbohydrate chemistry: Glycal and C-glycoside synthesis
Spencer, Roxanne P.,Schwartz, Jeffrey
, p. 2103 - 2112 (2000)
Titanocene(III) chloride and zirconcene(III) chloride are effective and mild reagents for radical generation in organic synthesis. In carbohydrate chemistry, these species are useful for the conversion of glycosyl halides to glycals, and for the stereospecific preparation of C-glycosides. In all cases, the 1-glycosyl radical is an active intermediate, generated by reaction of carbohydrate substrates with the organometallic. (C) 2000 Elsevier Science Ltd.
Diastereoselective Synthesis of Thioglycosides via Pd-Catalyzed Allylic Rearrangement
Jiang, Xuefeng,Li, Jiagen,Wang, Ming
supporting information, p. 9053 - 9057 (2021/11/30)
Stereoselective glycosylation is challenging in carbohydrate chemistry. Herein, stereoselective thioglycosylation of glycals via palladium-catalyzed allylic rearrangement yields various substituents on α-isomer thioglycosides. Two comprehensive series of aryl and benzyl thioglycosides were obtained via a combination of thiosulfates with glycals derived from glucose, arabinose, galactose, and rhamnose. Furthermore, diosgenyl α-l-rhamnoside and isoquercitrin achieved selectivity via stereospecific [2,3]-sigma rearrangements of α-sulfoxide-rhamnoside and α-sulfoxide-glucoside, respectively.
Method for efficiently constructing 1, 2-cis-2-nitro-glucoside and galactoside
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Paragraph 0038; 0062, (2021/08/11)
The invention discloses a method for efficiently constructing 1, 2-cis-2-nitro-glucoside and 1, 2-cis-2-nitro-galactoside, and belongs to the technical field of organic synthesis. According to the preparation method, the 1, 2-cis-2-nitro-glucoside and the 1, 2-cis-2-nitro-galactoside can be efficiently prepared through one-step synthesis. According to the present invention, the organic catalysis stereoselective glycosylation method is successfully applied to the sugar chemical total synthesis so that the problem of the construction of the 1, 2-cis-glucosidic bond between the most key sugar units is solved, and the foundation is established for the completion of the subsequent poly O-antigen total synthesis. The work has important reference value for related immunological research and vaccine development in the future.
