3068-31-3Relevant articles and documents
"Click" glycodendrimers containing 27, 81, and 243 modified xylopyranoside termini
Camponovo, Jeremy,Hadad, Caroline,Ruiz, Jaime,Cloutet, Eric,Gatard, Sylvain,Muzart, Jacques,Bouquillon, Sandrine,Astruc, Didier
, p. 5071 - 5074 (2009)
(Chemical Equation Presented) A series of large glycodendrimers containing 27, 81, and 243 terminal modified xylose branches from the first (G 1-27) to the third generation (G3-243) were synthesized from 2′-azidoethyl 2,3,4-tri-O-acetyl-β-D-xylopyranoside and alkynyl-terminated dendrimers by "click" chemistry that is confirmed to be an excellent method to obtain large glycodendrimers exemplified by the use of modified xylose. The dendrimers were first characterized by 1H NMR, 13C{1H} NMR, elemental analysis, and IR spectroscopy. The size progression in the series was also demonstrated using both DOSY NMR and size exclusion chromatography (SEC), the latter technique showing the good polydispersity of all the dendrimers. The size measured by dynamic light scattering (DLS) for the dendrimer G3-243 is close to that obtained by the DOSY NMR method.
Tandem β-elimination-Morita-Baylis-Hillman reaction in α,β-unsaturated sugar aldehydes
Areces, Pilar,Carrasco, Esther,Mancha, Alicia,Plumet, Joaquin
, p. 946 - 948 (2006)
The first Morita-Baylis-Hillman reaction of a 1-formylbutadiene derivative is reported. In addition, a convenient synthesis of 2-acetoxy-4-formylbutadiene derivatives starting from easily available D-galactal and D-arabinal is also described. Georg Thieme Verlag Stuttgart.
Photocatalyzed reductive fluoroalkylation of 2-acetoxyglycals towards the stereoselective synthesis of α-1-fluoroalkyl-: C -glycosyl derivatives
Mora Flores, Erwin W.,Postigo, Al,Uhrig, María Laura
, p. 8724 - 8734 (2020)
A benign, efficient, regio- and stereoselective protocol for the syntheses of α-1-fluoroalkyl-C-glycosyl compounds bearing CF3, C4F9, and C6F13 substituents on the anomeric carbon has been developed by a new methodology starting from 2-acetoxyglycals for the first time. Remarkably, the reactions proceeded in only one step, through the visible light-photocatalyzed reductive fluoroalkylation of 2-acetoxyglycals by means of an Ir photocatalyst and employed commercially available fluoroalkyl iodides n-CnF2n+1-I (n = 1, 4, 6) as a source of fluoroalkyl radicals.
Excited-State Palladium-Catalyzed 1,2-Spin-Center Shift Enables Selective C-2 Reduction, Deuteration, and Iodination of Carbohydrates
Zhao, Gaoyuan,Yao, Wang,Mauro, Jaclyn N.,Ngai, Ming-Yu
supporting information, p. 1728 - 1734 (2021/02/06)
Excited-state catalysis, a process that involves one or more excited catalytic species, has emerged as a powerful tool in organic synthesis because it allows access to the excited-state reaction landscape for the discovery of novel chemical reactivity. Herein, we report the first excited-state palladium-catalyzed 1,2-spin-center shift reaction that enables site-selective functionalization of carbohydrates. The strategy features mild reaction conditions with high levels of regio- and stereoselectivity that tolerate a wide range of functional groups and complex molecular architectures. Mechanistic studies suggest a radical mechanism involving the formation of hybrid palladium species that undergoes a 1,2-spin-center shift followed by the reduction, deuteration, and iodination to afford functionalized 2-deoxy sugars. The new reactivity will provide a general approach for the rapid generation of natural and unnatural carbohydrates.
Chemical synthesis of 5’-β-glycoconjugates of vitamin B6
Bachmann, Thomas,Schnurr, Christian,Zainer, Laura,Rychlik, Michael
supporting information, (2020/02/15)
Various 5’-β-saccharides of pyridoxine, namely the mannoside, galactoside, arabinoside, maltoside, cellobioside and glucuronide, were synthesized chemically according to KOENIGS-KNORR conditions using α4,3-O-isopropylidene pyridoxine and the respective acetobromo glycosyl donors with AgOTf (3.0 eq.) and NIS (3.0 eq.) as promoters at 0 °C. Furthermore, 5’-β-[13C6]-labeled pyridoxine glucoside (PNG) was prepared starting from [13C6]-glucose and pyridoxine. Additionally, two strategies were examined for the synthesis of 5’-β-pyridoxal glucoside (PLG).
