Uronic acids are carbohydrates present in relevant biologically active compounds. Most of the latter are glycosides or oligosaccharides linked by their anomeric carbon, so their synthesis requires glycoside-bond formation. The activation of this anomeric center remains difficult due to the presence of the electron-withdrawing C-5 carboxylic group. Herein we present an overview of glucuronidatio...

The deacylation of glucose, galactose and mannose pentaacetates, galactose and mannose penta(3-bromo)benzoates, as well as the dealkylation of 2,3,4,6-tetra-O-acetyl and 2,3,4,6-tetra-O-(3-bromo)benzoyl methyl alpha-D-glucopyranosides have been studied. In addition, a computational study on the deacylation of beta-D-glucose pentaacetate has been carried out with density functional theory (B3LYP...

A non-conventional vaporization method, using laser ablation of solid NaCl doped with d-erythrose, has been used to bring this sugar into the gas phase for rotational study. The jet cooled rotational spectrum of this C4 monosaccharide reveals the existence of two furanose forms, one α envelope and one β twist. Cooperative hydrogen bond networks and the anomeric effect have been found to be the ...

Retraction of ‘[TEATNM] and [TEATCM] as novel catalysts for the synthesis pyridine-3,5-dicarbonitriles via anomeric-based oxidation’ by Saeed Baghery et al. , New J. Chem. 2017, 41 9276–9290, https://doi.org/10.1039/C7NJ01934C.

In the title compound, C(8)H(8)N(2)O, the N-CH(2) and CH(2)-O bond lengths can be correlated to the manifestation of an anomeric effect in the N-CH(2)-O moiety. In the crystal, inter-molecular O-H⋯N hydrogen bonds link the mol-ecules into zigzag chains, with graph-set motif C(6), parallel to [001]. These chains are further linked into sheets by weak nonclassical C-H⋯O hydrogen bonds.

nbo analysis, hybrid density functional theory (b3lyp/6-311+g**) and ab initio molecular orbital (hf/6-311+g**) based methods were used to study the anomeric effects (ae), electrostatic interactions, dipole-dipole interactions and steric repulsion effects on the conformational properties of 2-methoxy- (1), 2-methylthio- (2), 2-methylseleno- (3), 2-fluoro- (4), 2-chloro- (5) and 2-bromocyclohexa...

Heparin and low molecular weight heparins are polydisperse polysaccharides with a degree of polymerization ranging from 4 to approximately 40. The determination of their average molecular weights has traditionally relied on size exclusion chromatography involving the use of oligosaccharides of known size and molecular weight as standards. 13C NMR spectroscopy is applied for the first time to ob...

It has been shown that the acetamido methyl protons of N-acetyl-D-glucosamine undergo a chemical shift to higher fields in their proton magnetic resonance spectrum when the inhibitor is bound to lysozyme. The observed chemical shift in the presence of the enzyme is different for the CP and /3-anomeric forms of Z-acetamido-Z-deoxy-D-glucopyranose indicating either a difference in the afhnity of ...

Glycoside bond formation generally requires activation of the sugar at the anomeric center. To this end, anomeric oxygen exchange reactions, resulting in the Koenigs±Knorr method and variations or, alternatively, activation through retention of the anomeric oxygen, resulting in the trichloroacetimidate method and in the phosphite method, have been proposed. The successful application of the tri...

Some time ago we reported the oxidation of 2,3-unsaturated hexopyranosides and 2-Cmethylene glycosides with hydrogen peroxide in the presence of molybdenum trioxide catalyst to give the corresponding anomeric hydroperoxides 1-5. Relatively stable hydroperoxides 1-5 were used for enantioselective oxidation of prochiral alcohols and sulfides in the presence of Ti(OiPr)4 with stereoselectivities v...