21893-05-0Relevant articles and documents
X-ray and NMR studies on the rotational isomerism about the C(5)-C(6) bond of 6-substituted methyl 2,3,4,-tri-O-acetyl-6-X-α-D-glucopyranoside derivatives
Mentzafos, D.,Polissiou, M.,Grapsas, I.,Hountas, A.,Georgiadis, M.,Terzis, A.
, p. 157 - 164 (1995)
The rotamers about the C(5)-C(6) bond of a series of 2,3,4-tri-O-acetyl-6-X-α-D-glucopyranoside derivatives resulting by substitution at C(6) or O(6) have been studied with 1H-NMR spectroscopy (400 MHz) and X-ray structure analysis.The methyl 2,3,4-tri-O-acetyl-6-O-triphenyl-methyl-α-D-glucopyranoside and the N-(1-O-methyl-2,3,4-tri-O-acetyl-α-D-glucopyranose-6-yl)-pyridinium nitrate crystallize in the P21 space group with a = 14.940(1), b = 11.232(1), c = 9.0773(7), and β = 94.480(7) and a = 7.670(1), b = 15.384(3), c = 9.624(1) and β = 104.90(1), respectively; the methyl 2,3,4-tri-O-acetyl-6-O-nitro-α-D-glucopyranoside and methyl 2,3,4-tri-O-acetyl-6-O-deoxy-6-iodo-α-D-glucopyrano-side crystallize in the P212121 space group with a = 5.630(1), b = 14.360(1) and c = 22.388(3), and a = 5.556(1), b = 14.303(6) and c = 21.963(6), respectively.KEY WORDS: Derivatives, rotamers, 1H-NMR, x-ray, structure, 2,3,4,tri-O-acetyl-6-X-α-D-glucopyranosides.
Synthesis and surface-active properties of amphiphilic 6-aminocarbonyl derivatives of D-glucose
Maunier, Valerie,Boullanger, Paul,Lafont, Dominique,Chevalier, Yves
, p. 49 - 57 (1997)
Several 6-amido-6-deoxy derivatives of methyl α-D-glucopyranoside and D-glucopyranose were prepared via peracetylated 6-azido-6-deoxy or 6-deoxy-6-isocyanato intermediates. These compounds displayed high Krafft temperatures which could result from hydrogen bonding between NH and O-5. Their tensio-active properties above the Krafft temperature were compared with Hecameg (methyl 6-O-(N-heptylcarbamoyl)-α-D-glucopyranoside).
Synthesis and Evaluation of the Biological Profile of Novel Analogues of Nucleosides and of Potential Mimetics of Sugar Phosphates and Nucleotides
Xavier, Nuno M.,Lucas, Susana D.,Jorda, Radek,Schwarz, Stefan,Loesche, Anne,Csuk, René,Oliveira, M. Concei??o
supporting information, p. 2663 - 2672 (2015/11/27)
The synthesis of purine/triazole 6'-isonucleosides and of glucuronic acid/glucuronamide-derived N-glycosylsulfonohydrazides through efficient and stereo- or regioselective methodologies is described. Their structures were envisaged to mimic nucleosides, s
AMYLOID TARGETING AGENTS AND METHODS OF USING THE SAME
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Paragraph 00834, (2015/11/10)
Provided herein is the design and synthesis of novel molecular rotor fluorophores useful for detection of amyloid or amyloid like proteins. The fluorophores are designed to exhibit enhanced fluorescence emission upon associating with amyloid or amyloid like proteins as compared to unbound compound. Also disclosed herein are the methods for treating of diseases associated with an amyloid or amyloid like proteins.
Composition and methods related to modification of 5-hydroxymethylcytosine (5-hmC)
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Page/Page column, (2014/06/11)
The present invention relates generally to the field of molecular biology. More particularly, it concerns methods and compositions for detecting, evaluating, and/or mapping 5-hydroxymethyl-modified cytosine bases within a nucleic acid molecule.
Design and synthesis of hydrolytically stable multivalent ligands bearing thiodigalactoside analogues for peanut lectin and human galectin-3 binding
Cagnoni, Alejandro J.,Kovensky, José,Uhrig, María Laura
, p. 6456 - 6467 (2014/08/05)
Herein, we describe the design and synthesis of a novel family of hydrolytically stable glycoclusters bearing thiodigalactoside (TDG) analogues as recognition elements of β-galactoside binding lectins. The TDG analogue was synthesized by thioglycosylation of a 6-S-acetyl-α-d-glucosyl bromide with the isothiouronium salt of 2,3,4,6-tetra-O-acetyl-β-d-galactose. Further propargylation of the TDG analogue allowed the coupling to azido-functionalized oligosaccharide scaffolds through copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) under microwave activation. The final mono-, di-, and tetravalent ligands were resistant to enzymatic hydrolisis by Escherichia coli β-galactosidase. Binding affinities to peanut agglutinin and human galectin-3 were measured by isothermal titration calorimetry which showed Ka constants in the micromolar range as well as a multivalent effect. Monovalent ligand exhibited a binding affinity higher than that of thiodigalactoside. Docking studies performed with a model ligand on both β-galactoside binding lectins showed additional interactions between the triazole ring and lectin amino acid residues, suggesting a positive effect of this aromatic residue on the biological activity.
Quantifying the electronic effects of carbohydrate hydroxy groups by using aminosugar models
Pedersen, Christian M.,Olsen, Jacob,Brka, Azra B.,Bols, Mikael
scheme or table, p. 7080 - 7086 (2011/07/08)
Methyl amino-deoxy-glycosides with α- and β-gluco, α-galacto, or α-manno stereochemistry with the amino functionality in each of the four possible non-anomeric positions have been synthesized and their pKa values determined by titration. These
Development and characterization of lysine based tripeptide analogues as inhibitors of Sir2 activity
Chakrabarty, Subhra Prakash,Ramapanicker, Ramesh,Mishra, Roli,Chandrasekaran, Srinivasan,Balaram, Hemalatha
scheme or table, p. 8060 - 8072 (2010/03/24)
Sirtuins are NAD+ dependent deacetylases that modulate various essential cellular functions. Development of peptide based inhibitors of Sir2s would prove useful both as pharmaceutical agents and as effectors by which downstream cellular alterations can be monitored. Click chemistry that utilizes Huisgen's 1,3-dipolar cycloaddition permits attachment of novel modifications onto the side chain of lysine. Herein, we report the synthesis of peptide analogues prepared using click reactions on Nε-propargyloxycarbonyl protected lysine residues and their characterization as inhibitors of Plasmodium falciparum Sir2 activity. The peptide based inhibitors exhibited parabolic competitive inhibition with respect to acetylated-peptide substrate and parabolic non-competitive inhibition with NAD+ supporting the formation of EI2 and E·NAD+·I2 complexes. Cross-competition inhibition analysis with the non-competitive inhibitor nicotinamide (NAM) ruled out the possibility of the NAM-binding site being the second inhibitor binding site, suggesting the presence of a unique alternate pocket accommodating the inhibitor. One of these compounds was also found to be a potent inhibitor of the intraerythrocytic growth of P. falciparum with 50% inhibitory concentration in the micromolar range.
A mild one-step selective conversion of primary hydroxyl groups into azides in mono- and oligo-saccharides
Jimenez Blanco, Jose Luis,Garcia Fernandez, Jose Manuel,Gadelle, Andree,Defaye, Jacques
, p. 367 - 372 (2007/10/03)
The direct azidation reaction of several monosaccharide methyl glycopyranosides, sucrose, α,α-trehalose, cyclomaltohexaose and cyclomaltoheptaose with sodium azide in the presence of triphenylphosphine-carbon tetrabromide is reported. The optimal reaction conditions require pre-formation of the reactive species before addition of the sugar substrate. Formation of the primary azidodeoxy compound is accompanied by simultaneous formation of the corresponding primary bromodeoxy and 3,6-anhydro derivatives in the glycopyranoside series, the former being transformed in situ into the azide by quenching of the reaction mixture with methanol before increasing the temperature. Interestingly, good selectivity towards the primary C-6 position of the glucopyranosyl moiety as compared to the fructofuranosyl one was observed in the case of sucrose, advantage of which has been taken in an improved preparation of 2,3,4,1',3',4',6'-hepta-O-acetyl-6-azido-6-deoxysucrose (45% yield from sucrose). Sodium or lithium azide reagents were found equally effective. The azide functionality could be reduced without previous purification and the resulting amino sugar isolated by cation-exchange column chromatography, as illustrated for the preparation of 6(I)-amino-6(I)-deoxycyclomaltoheptaose.
