71049-35-9Relevant academic research and scientific papers
General method for synthesizing pyranoid glycals. A new route to allal and gulal derivatives
Boutureira, Omar,Rodriguez, Miguel Angel,Matheu, M. Isabel,Diaz, Yolanda,Castillon, Sergio
, p. 673 - 675 (2006)
Pyranoid glycals of all configurations can be obtained from pentoses through an olefination-cyclization-elimination sequence. The elimination can be carried out with excellent yields under radical conditions or by using common reductive reagents such as Z
Iterative Synthesis of 2-Deoxyoligosaccharides Enabled by Stereoselective Visible-Light-Promoted Glycosylation
Guo, Zhen-Yan,Liu, Kai-Meng,Liu, Meng,Liu, Miao,Qin, Xian-Jin,Wang, Peng-Yu,Xiong, De-Cai,Xue, Wan-Ying,Ye, Xin-Shan
, (2022/02/21)
The photoinitiated intramolecular hydroetherification of alkenols has been used to form C?O bonds, but the intermolecular hydroetherification of alkenes with alcohols remains an unsolved challenge. We herein report the visible-light-promoted 2-deoxyglycosylation of alcohols with glycals. The glycosylation reaction was completed within 2 min in a high quantum yield (?=28.6). This method was suitable for a wide array of substrates and displayed good reaction yields and excellent stereoselectivity. The value of this protocol was further demonstrated by the iterative synthesis of 2-deoxyglycans with α-2-deoxyglycosidic linkages up to a 20-mer in length and digoxin with β-2-deoxyglycosidic linkages. Mechanistic studies indicated that this reaction involved a glycosyl radical cation intermediate and a photoinitiated chain process.
Azomethine ylide cycloaddition of 2-C-formyl glycals with α-amino acids for the synthesis of substituted pyrroles
Reddy, V. Veerabadhra,Reddy, B.V. Subba
, (2021/09/03)
A novel strategy has been devised for the synthesis of pyrrole based acyclo-C-nucleosides, in particular an open-chain sugar substituted pyrrole derivatives by means of the condensation of 2-C-formyl glycals with α-amino acids through an intramolecular azomethine cycloaddition under thermal conditions. The use of cyclic α-amino acids provides the corresponding bicyclic pyrrole derivatives. This is a first report on the synthesis of pyrrole based acyclo-C-nucleosides. 2009 Elsevier Ltd. All rights reserved.
Palladium-Catalyzed One-Pot Stereospecific Synthesis of 2-Deoxy Aryl C-Glycosides from Glycals and Anilines in the Presence of tert-Butyl Nitrite
Kandasamy, Jeyakumar,Singh, Adesh Kumar,Venkatesh, Rapelly
, p. 4215 - 4230 (2019/11/14)
The palladium-catalyzed one-pot synthesis of 2,3-deoxy-3-keto aryl C-glycosides is achieved from glycals and anilines in the presence of tert-butyl nitrite and aqueous HBF 4 under mild conditions. This one-pot method stereospecifically provides α-and β-Aryl glycosides (≥19:1 by NMR) in good yields at room temperature. The configuration at the C-3 position in the glycal determines the anomeric selectivity (i.e., α or β) of the desired products.
TEMPO-Catalyzed Oxidation of 3- O-Benzylated/Silylated Glycals to the Corresponding Enones Using a PIFA-Water Reagent System
Chennaiah, Ande,Verma, Ashish Kumar,Vankar, Yashwant D.
, p. 10535 - 10540 (2018/09/12)
A simple, highly efficient and regiospecific method for the direct conversion of 3-O-benzylated as well as silylated glycals into the corresponding enones has been developed using PIFA-TEMPO and water reagent system. The reaction is scalable on a gram sca
Synthesis of Altrose Poly-amido-saccharides with β-N-(1→2)- d -amide Linkages: A Right-Handed Helical Conformation Engineered in at the Monomer Level
Xiao, Ruiqing,Dane, Eric L.,Zeng, Jialiu,McKnight, Christopher J.,Grinstaff, Mark W.
, p. 14217 - 14223 (2017/10/17)
The design and synthesis of amide-linked saccharide oligomers and polymers, which are predisposed to fold into specific ordered secondary structures, is of significant interest. Herein, right-handed helical poly amido-saccharides (PASs) with β-N-(1→2)-d-amide linkages are synthesized by the anionic ring-opening polymerization of an altrose β-lactam monomer (alt-lactam). The right-handed helical conformation is engineered into the polymers by preinstalling the β configuration of the lactam ring in the monomer via the stereospecific [2+2] cycloaddition of trichloroacetyl isocyanate with a d-glycal possessing a 3-benzyloxy group oriented to the α-face of the pyranose. The tert-butylacetyl chloride initiated polymerization of the alt-lactam proceeds smoothly to afford stereoregular polymers with narrow dispersities. Birch reduction of the benzylated polymers gives water-soluble altrose PASs (alt-PASs) in high yields without degradation of the polymer backbone. Circular dichroism analysis shows the alt-PASs adopt a right-handed helical conformation in aqueous solutions. This secondary conformation is stable over a wide range of different conditions, such as pH (2.0 to 12.0), temperature (5 to 75 °C), ionic salts (2.0 M LiCl, NaCl, and KCl), as well as in the presence of protein denaturants (4.0 M urea and guanidinium chloride). Cytotoxicity studies reveal that the alt-PASs are nontoxic to HEK, HeLa, and NIH3T3 cells. The results showcase the ability to direct solution conformation of polymers through monomer design. This approach is especially well-suited and straightforward for PASs as the helical conformations formed result from constraints imposed by the relatively rigid and sterically bulky repeating units.
Fluorine-directed β-galactosylation: Chemical glycosylation development by molecular editing
Durantie, Estelle,Bucher, Christoph,Gilmour, Ryan
, p. 8208 - 8215 (2012/08/27)
Validation of the 2-fluoro substituent as an inert steering group to control chemical glycosylation is presented. A molecular editing study has revealed that the exceptional levels of diastereocontrol in glycosylation processes by using 2-fluoro-3,4,6-tri-O-benzyl glucopyranosyl trichloroacetimidate (TCA) scaffolds are a consequence of the 2R,3S,4S stereotriad. This study has also revealed that epimerization at C4, results in a substantial enhancement in β-selectivity (up to β/α 300:1). Copyright
Stereoelectronic factors in the stereoselective epoxidation of glycals and 4-deoxypentenosides
Alberch, Laura,Cheng, Gang,Seo, Seung-Kee,Li, Xuehua,Boulineau, Fabien P.,Wei, Alexander
, p. 2532 - 2547 (2011/06/19)
Glycals and 4-deoxypentenosides (4-DPs), unsaturated pyranosides with similar structures and reactivity profiles, can exhibit a high degree of stereoselectivity upon epoxidation with dimethyldioxirane (DMDO). In most cases, the glycals and their corresponding 4-DP isosteres share the same facioselectivity, implying that the pyran substituents are largely responsible for the stereodirecting effect. Fully substituted dihydropyrans are subject to a "majority rule", in which the epoxidation is directed toward the face opposite to two of the three groups. Removing one of the substituents has a variable effect on the epoxidation outcome, depending on its position and also on the relative stereochemistry of the remaining two groups. Overall, we observe that the greatest loss in facioselectivity for glycals and 4-DPs is caused by removal of the C3 oxygen, followed by the C5/anomeric substituent, and least of all by the C4/C2 oxygen. DFT calculations based on polarized-π frontier molecular orbital (PPFMO) theory support a stereoelectronic role for the oxygen substituents in 4-DP facioselectivity, but less clearly so in the case of glycals. We conclude that the anomeric oxygen in 4-DPs contributes toward a stereoelectronic bias in facioselectivity whereas the C5 alkoxymethyl in glycals imparts a steric bias, which at times can compete with the stereodirecting effects from the other oxygen substituents.
Synthesis of 2-iodoglycals, glycals, and 1,1′-disaccharides from 2-deoxy-2-iodopyranoses under dehydrative glycosylation conditions
Rodriguez, Miguel Angel,Boutureira, Omar,Matheu, M. Isabel,Diaz, Yolanda,Castillon, Sergio,Seeberger, Peter H.
, p. 8998 - 9001 (2008/03/13)
(Chemical Equation Presented) Treatment of 2-deoxy-2-iodopyranoses under dehydrative glycosylation conditions afforded pyranose glycals, 2-iodoglycals, and 1,1′-disaccharides instead of the expected glycoside products. While the product distribution revea
