28022-14-2Relevant academic research and scientific papers
Self-Promoted Glycosylation for the Synthesis of β-N-Glycosyl Sulfonyl Amides
Ma?a, Patrycja,Pedersen, Christian Marcus
supporting information, p. 5685 - 5689 (2021/08/30)
N-Glycosyl N-sulfonyl amides have been synthesized by a self-promoted glycosylation, i. e. without any catalysts, promotors or additives. When the reactions were carried out at lower temperatures a mixture of N- and O-glycosides were observed, where the latter rearranged to give the β-N-glycosides at elevated temperatures. By this method sulfonylated asparagine derivatives can be selectively β-glycosylated in high yields by trichloroacetimidate glycosyl donors of different reactivity including protected glucosamine derivatives. The chemoselectivity in the glycosylations as well as the rearrangements from O-glycosides to β-N-glycosides gives information of the glycosylation mechanism. This method gives access to glycosyl sulfonyl amides under mild conditions.
Concise Synthesis of 1-Thioalkyl Glycoside Donors by Reaction of Per-O-acetylated Sugars with Sodium Alkanethiolates under Solvent-Free Conditions
Dong, Hai,Feng, Guang-Jing,Guo, Yang-Fan,Liu, Chun-Yang,Luo, Tao
, (2022/02/07)
A relatively green method for synthesizing 1-thioalkyl glycosides has been developed, where sodium alkanethiolates were used to react with per-O-acetylated sugars instead of odorous alkyl mercaptans in the presence of BF3·Et2O without the use of solvents under mild conditions. Furthermore, we found that 1,2-trans-β-thioglycosides can be converted into corresponding 1,2-cis-α-thioglycosides in the presence of trifluoromethanesulfonic acid in nonpolar solvents under mild conditions. This provides a simple and efficient new approach for synthesizing challenging 1,2-cis-α-thioglycosides.
Synthesis of Glycosylated 1-Deoxynojirimycins Starting from Natural and Synthetic Disaccharides
Liu, Bing,van Mechelen, Jeanine,van den Berg, Richard J. B. H. N.,van den Nieuwendijk, Adrianus M. C. H.,Aerts, Johannes M. F. G.,van der Marel, Gijsbert A.,Codée, Jeroen D. C.,Overkleeft, Herman S.
, p. 118 - 129 (2019/01/04)
Iminosugars are an important class of natural products and have been subject to extensive studies in organic synthesis, bioorganic chemistry and medicinal chemistry, yet only a limited number of these studies are on glycosylated iminosugars. Here, a general route of synthesis is presented towards glycosylated 1-deoxynojirimycin derivatives based on the oxidation–reductive amination protocol that in the past has also been shown to be a versatile route towards 1-deoxynojirimycin. The strategy can be applied on commercial disaccharides, as shown in four examples, as well as on disaccharides that are not commercially available and are synthesized for this purpose, as shown by a fifth example.
Iridium catalysis: Reductive conversion of glucan to xylan
Pedersen, Martin J?ger,Madsen, Robert,Clausen, Mads Hartvig
supporting information, p. 952 - 955 (2018/02/07)
By using iridium catalysed dehydrogenative decarbonylation, we converted a partly protected cellobioside into a fully protected xylobioside. We demonstrate good yields with two different aromatic ester protecting groups. The resulting xylobioside was directly used as glycosyl donor in further synthesis of a xylooctaose.
A highly efficient TEMPO mediated oxidation of sugar primary alcohols into uronic acids using 1-chloro-1,2-benziodoxol-3(1H)-one at room temperature
Tiwari, Varsha,Badavath, Vishnu Nayak,Singh, Adesh Kumar,Kandasamy, Jeyakumar
supporting information, p. 2511 - 2514 (2018/05/29)
Oxidation of various sugar primary alcohols into corresponding uronic acids was demonstrated using 1-chloro-1,2-benziodoxol-3(1H)-one and TEMPO. The reaction proceeds at room temperature in good to excellent yields. Primary alcohols get oxidized selective
Efficient one-pot per-: O -acetylation-thioglycosidation of native sugars, 4,6- O -arylidenation and one-pot 4,6- O -benzylidenation-acetylation of S -/ O -glycosides catalyzed by Mg(OTf)2
Mukherjee, Mana Mohan,Basu, Nabamita,Chaudhury, Aritra,Ghosh, Rina
, p. 109301 - 109314 (2016/11/30)
A sequential one-pot per-O-acetylation-S-/O-glycosidation of native mono and disaccharides under solvent free conditions using 0.5 mole% of Mg(OTf)2 as a non-hygroscopic, recyclable catalyst is reported. Regioselective 4,6-O-arylidenation of glycosides and thioglycosides with benzaldehyde or p-methoxybenzaldehyde dimethyl acetal is catalyzed by 10 mole% of Mg(OTf)2 to produce the corresponding 4,6-O-arylidenated product in high yields. Mg(OTf)2 can also mediate sequential one-pot benzylidenation-acetylation of mono and disaccharide based glycosides and thioglycosides in high yield.
Solvent-free bismuth oxycarbonate-mediated mechanochemical glycosylation: A simple greener alternative to access O-/S-glycosides efficiently
Sethi, Kashmir Prasad,Kartha, K.P. Ravindranathan
, p. 132 - 135 (2016/09/23)
Preparation of a variety of per-O-acylated O- and S-glycosides of a set of commonly encountered mono- and disaccharides has been achieved effectively by solvent-free grinding of the corresponding acetylated/benzoylated glycosyl bromide and the desired acceptor alcohol/thiol in the presence of bismuth carbonate in a planetary ball mill. The method is simple, requires short reaction time periods and is practical allowing it to be performed at a milligram-to multi-gram scale as required. In the cases where the product is crystalline, it was often obtained in practically pure form by crystallization (and without the need for chromatographic isolation).
Useful approach to the synthesis of aryl thio- and selenoglycosides in the presence of rongalite
Venkateswarlu, Cheerladinne,Gautam, Vibha,Chandrasekaran, Srinivasan
, p. 48 - 53 (2014/08/18)
A simple, mild, and cost effective methodology has been developed for the synthesis of aryl thio-and selenoglycosides from glycosyl halides and diaryl dichalcogenides. Diaryl dichalcogenides undergo reductive cleavage in the presence of rongalite (HOCH2SO2Na) to generate a chalcogenide anion in situ followed by reaction with glycosyl halides to furnish the corresponding aryl thio- and selenoglycosides in excellent yields. Using this protocol, synthesis of 4-methyl-7-thioumbelliferyl-β-d-cellobioside (MUS-CB), a fluorescent non-hydrolyzable substrate analogue for cellulases has been achieved.
A divergent approach to the synthesis of iGb3 sugar and lipid analogues via a lactosyl 2-azido-sphingosine intermediate
Cheng, Janice M. H.,Dangerfield, Emma M.,Timmer, Mattie S. M.,Stocker, Bridget L.
supporting information, p. 2729 - 2736 (2014/05/06)
Isoglobotrihexosylceramide (iGb3, 1) is an immunomodulatory glycolipid that binds to CD1d and is presented to the T-cell receptor (TCR) of invariant natural killer T (iNKT) cells. To investigate how modifications to the lipid tail or terminal sugar residu
In(III) triflate-mediated solvent-free synthesis and activation of thioglycosides by ball milling and structural analysis of long chain alkyl thioglycosides by TEM and quantum chemical methods
Kumar, Vajinder,Taxak, Nikhil,Jangir, Ramniwas,Bharatam, Prasad V.,Kartha, K. P. Ravindranathan
, p. 3427 - 3439 (2014/05/06)
Conventional solution-phase synthesis of thioglycosides from glycosyl acetates and thiols in the presence of In(III) triflate as reported for benzyl thioglucoside failed when applied to the synthesis of phenolic and alkyl thioglycosides. But, it was achieved in high efficiency and diastereospecificity with ease by solvent-free grinding in a ball mill. The acetates in turn were also obtained by the homogenization of free sugars with stoichiometric amounts of acetic anhydride and catalytic In(OTf)3 in the mill as neat products. Per-O-benzylated thioglycosides on grinding with an acceptor sugar in the presence of In(OTf)3 yield the corresponding O-glycosides efficiently. The latter in the case of a difficult secondary alcohol was nearly exclusive (>98%) in 1,2-cis-selectivity. In contrast, the conventional methods for this purpose require use of a coreagent such as NIS along with the Lewis acid to help generate the electrophilic species that actually is responsible for the activation of the thioglycoside donor in situ. The distinctly different self-assembling features of the peracetylated octadecyl 1-thio-α- and β-d-galactopyranosides observed by TEM could be rationalized by molecular modeling.
