1769-06-8

Upstream product

• 75-77-4 chloro-trimethyl-silane 
• 617-04-9 (2R,3S,4S,5S,6S)-2-(hydroxymethyl)-6-methoxytetrahydro-2H-pyran-3,4,5-triol 
• 7677-24-9 trimethylsilyl cyanide 
• 25561-30-2 trimethylsilyl 2,2,2-trifluoro-N-(trimethylsilyl)acetimidate 
• 999-97-3 1,1,1,3,3,3-hexamethyl-disilazane 
• 67-56-1 methanol 
• 25561-30-2 N,O-Bis(trimethylsilyl)trifluoroacetamide 
• 168138-24-7 Carbamic acid (2R,3R,4S,5S,6R)-3,5-dihydroxy-2-hydroxymethyl-6-((2R,3S,4S,5S,6S)-2,4,5-trihydroxy-6-hydroxymethyl-tetrahydro-pyran-3-yloxy)-tetrahydro-pyran-4-yl ester 

Downstream Products

• 492-93-3 1,5-anhydro-D-mannitol 
• 13121-61-4 tetra-O-acetyl-1,5-anhydro-D-mannitol 
• 72656-05-4 C₂₀H₂₈O₁₁ 
• 3162-96-7 methyl-4,6-O-phenylmethylene-α-D-mannopyranoside 

Relevant academic research and scientific papers

Binding of the Bacterial Adhesin FimH to Its Natural, Multivalent High-Mannose Type Glycan Targets

Multivalent carbohydrate-lectin interactions at host-pathogen interfaces play a crucial role in the establishment of infections. Although competitive antagonists that prevent pathogen adhesion are promising antimicrobial drugs, the molecular mechanisms underlying these complex adhesion processes are still poorly understood. Here, we characterize the interactions between the fimbrial adhesin FimH from uropathogenic Escherichia coli strains and its natural high-mannose type N-glycan binding epitopes on uroepithelial glycoproteins. Crystal structures and a detailed kinetic characterization of ligand-binding and dissociation revealed that the binding pocket of FimH evolved such that it recognizes the terminal α(1-2)-, α(1-3)-, and α(1-6)-linked mannosides of natural high-mannose type N-glycans with similar affinity. We demonstrate that the 2000-fold higher affinity of the domain-separated state of FimH compared to its domain-associated state is ligand-independent and consistent with a thermodynamic cycle in which ligand-binding shifts the association equilibrium between the FimH lectin and the FimH pilin domain. Moreover, we show that a single N-glycan can bind up to three molecules of FimH, albeit with negative cooperativity, so that a molar excess of accessible N-glycans over FimH on the cell surface favors monovalent FimH binding. Our data provide pivotal insights into the adhesion properties of uropathogenic Escherichia coli strains to their target receptors and a solid basis for the development of effective FimH antagonists.

Phosphoryl mannopentaose and derivatives thereof, and preparation methods and application thereof

The invention provides phosphoryl mannopentaose as shown in a formula (I) and derivatives as shown in formula (II) to (XI) of phosphoryl mannopentaose, and preparation methods thereof. According to the preparation methods, reactivity is regulated and cont

Simple one-pot regioselective 6-O-phosphorylation of carbohydrates and trehalose desymmetrization

Biologically essential carbohydrate 6-phosphates, especially trehalose 6-phosphate, can be synthesized easily in excellent overall yields in 2 steps involving minimum protecting group manipulations. We can cleave the diphenylphosphate group for further synthetic objectives.

Characterization of ulvan extracts to assess the effect of different steps in the extraction procedure

An effective application development of the polysaccharide ulvan requires a comprehensive knowledge about the influence of the extraction process on composition of the extracts and in ulvan itself. In this context, the two main objectives of the present work are (1) the establishment of an efficient extraction process for ulvan and (2) development of an accurate characterization methodology to evaluate the extract composition and ulvan content. Three ulvan-rich extracts obtained by different schemes of extraction were studied. The methodology for the analysis was improved and a detailed analysis of extracted ulvan was provided. The polysaccharide is rich in ulvanobiuronic acid 3-sulfate type A [→4)-β-d-GlcAp-(1 → 4)-α-l-Rhap 3S-(1→], with minor amounts of ulvanobiuronic acid 3-sulfate type B [→4)-α-l-IdoAp-(1 → 4)-α-l-Rhap 3S-(1→]. The extract with the higher degree of purification is a high molecular weight polysaccharide (790 kDa) composed of rhamnose (22.4%), glucuronic acid (22.5%), xylose (3.7%), iduronic acid (3.1%) and glucose (1.0%). It is highly sulfated (32.2%) and contains 1.3% of proteins and 10.3% of inorganic material. Applying simple extraction scheme it was possible to obtain an extract from green algae with high content of ulvan without affecting the overall chemical structure of the polysaccharide.

TMSOTf-catalyzed silylation: Streamlined regioselective one-pot protection and acetylation of carbohydrates

A highly efficient TMSOTf-catalyzed HMDS silylation of sugars, which can easily be integrated with subsequent reactions in one-pot fashion, has been developed. Its usefulness was demonstrated by applications to streamlined regioselective one-pot protection and nonenzymatic acetylation of unprotected sugars. Monosaccharide and trehalose building blocks with orthogonally well-differentiated hydroxy groups were efficiently prepared starting with free sugars in one-pot fashion without the need for prior per-O-silylation. Regioselectively protected and acetylated building blocks were prepared directly from unprotected sugars in a one-pot manner involving up to five TMSOTf-catalyzed reactions, including a new TMSOTf-catalyzed silylation of carbohydrates. Copyright

Large-scale synthesis of D-mannose 6-phosphate and other hexose 6-phosphates

The syntheses of D-mannose 6-phosaphate (4), several D-mannopyranoside 6-phosphates, and methyl α-D-glucopyranoside 6-phosphate are described.Phophorylation of methyl 2,3,4-tri-O-(trimethylsilyl)-α-D-mannopyranoside (2) with phosphorus oxychloride followe

A convenient method for the cleavage of the D-mannosyl-L-gulose disaccharide from bleomycin-A2.

In order to elucidate the biological role of the sugar residue of the antitumor drug bleomycin, this was deglycosylated by beta-elimination under mild alkaline conditions, and by solvolysis with hydrogen fluoride. The latter procedure proved to be better because it led to the complete deglycosylation without modification of the peptide, thus allowing further biological investigations of this component.

An Efficient Synthesis of Anhydroalditols and Allyl C-Glycosides

Efforts to expedite production of anhydroalditols have led to a new, efficient synthesis of these compounds from alkyl glycosides.Silylation of the glycoside followed by reductive cleavage in the presence of triethylsilane and trimethylsilyl trifluoromethanesulfonate were carried out in the same reaction flask.Subsequent aqueous workup gave excellent yields of anhydroalditol(s).In some cases ring contraction was observed, but the use of bulkier silyl protecting groups gave greater yields of the expected product.This method was also shown to be an efficient means to prepare allyl C-glycosides, without any independent protecting or activating step, by simply replacing triethylsilane with allyltrimethylsilane in the synthetic scheme.