97590-76-6Relevant articles and documents
Intercepted dehomologation of aldoses by N-heterocyclic carbene catalysis-a novel transformation in carbohydrate chemistry
Draskovits, Markus,Kalaus, Hubert,Stanetty, Christian,Mihovilovic, Marko D.
, p. 12144 - 12147 (2019/10/21)
The development of an N-heterocyclic carbene (NHC) catalysed intercepted dehomologation of aldoses is reported. The unique selectivity of NHCs for aldehydes is exploited in the complex context of reducing sugars. Examples of strong substrate governance for either intercepted dehomologation or a subsequent redox-lactonisation were identified and mechanistically understood. More importantly, it was shown that catalyst design allowed the tuning of the selectivity of the reaction with structurally unbiased starting materials towards either of the two scenarios.
Preparation method of clostridium bolteae surface capsular polysaccharide structure derivative
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Paragraph 0060; 0073; 0076, (2018/08/28)
The invention discloses a preparation method of a clostridium bolteae surface capsular polysaccharide structure derivative and belongs to the field of sugar chemistry. The preparation method comprisesthe following steps: taking glucose as a glycosyl donor to obtain a target beta-glycosidic bond; then successfully synthesizing a disaccharide building block through an oxidization-reduction glucoseC-2 site method; then synthesizing a target oligosaccharide structure which takes the disaccharide building block as a repeating unit, such as the gram-positive bacterium surface capsular polysaccharide structure derivative [arrow3]-alpha-D-Manp-(1arrow4)-beta-D-Rhap-(1arrow]5-Linker. A reducing end of decaose is connected with a connecting arm and is used for connecting protein to form a glycoconjugate for carrying out immunology researches. The method provided by the invention has the advantages of simplicity, time saving, labor saving and low cost; the obtained clostridium bolteae surface capsular polysaccharide structure derivative is possibly used for developing and preparing medicine related to autism.
Synthesis of a 1,3 β-glucan hexasaccharide designed to target vaccines to the dendritic cell receptor, Dectin-1
Elsaidi, Hassan R.H.,Paszkiewicz, Eugenia,Bundle, David R.
, p. 96 - 106 (2015/04/14)
Transformation of 3-O-benzyl-1,2:5,6-di-O-isopropylidene-α-d-glucofuranose into 2,4,6-tri-O-benzoyl-3-O-benzyl glucopyranosyl imidate proceeded efficiently via crystalline benzyl and per-benzoylated derivatives. This imidate glycosylated di-O-isopropylidene-α-d-glucofuranose in high yield and glycosylation of the disaccharide after removal of the 3′-O-benzyl ether afforded the β1,3 linked trisaccharide in excellent yield. Di- and trisaccharides imidates were readily prepared from the furanose terminated glycosylation products but both were unreactive in glycosylation reaction with the debenzylated di- and trisaccharide alcohols. The 3′-O-benzyl perbenzoylated disaccharide pyranose derivative could be selectively debenzoylated and converted to the corresponding perbenzoylated 4,6:4′,6′-di-O-benzylidene derivative. Lewis acid catalyzed glycosidation gave the selectively protected disaccharide ethylthioglycoside in good overall yield. Glycosidation of this thioglycoside donor with 5-methoxycarbonylpentanol gave the disaccharide tether glycoside and after catalytic removal of benzyl ether the resulting disaccharide alcohol was glycosylated by the thioglycoside in a 2+2 reaction to yield a tetrasaccharide. Repetition of selective deprotection of the terminal 3-O-benzyl ether followed by glycosylation by the disaccharide thioglycoside gave a protected hexasaccharide. Hydrogenolysis of this hexasaccharide followed by transesterification and second hydrogenolysis to remove a residual benzyl group gave the target hexasaccharide glycoside 1 as a Dectin-1 ligand functionalized to permit covalent attachment to glycoconjugate vaccines and thereby facilitate improved antigen processing by dendritic cells.
