Copper-catalyzed, thermal or microwave promoted 1,3-dipolar cycloaddition (Click Reaction) of 2-propynyl and 3-butynyl 2,3,4-tri-O-acetyl-6-azido-6-deoxy-glycopyranosides in the D-gluco, D-galacto and D-manno series afford the corresponding dimeric cycloaddition products.

INTRODUCTION: Sialic acid (called neuraminic acid) is the designation given to a family of over 40 naturally occurring ninecarbon keto sugars acids derived from the parent compound 2-keto3-deoxy-5-acetamido-D-glyceroD-galacto-nonulosonic acid ( Nacetylneuraminic acid [Neu5Ac]). The sialic acids and related nonulosonates are unique in nature by representing the only nine-carbon sugars found in p...

abstract The stability of catalase in the reaction of hydrogen peroxide decomposition was studied in the presence of some potential stabilizers: ethylene glycol, glycerol, fructose, sucrose, fucose, ribitol and 2 nitro phenyl-#-D-galacto-pyranosid (niphegal). The sucrose, ethylene glycol and glycerol showed the best performance for long-term storage at 30°C. The stability of catalase increases ...

The heterocyclization reaction on thiosemicarbazones having the D-galacto, D-gluco and D-manno configuration was studied. We applied two different acetylating conditions, and the reaction products obtained were identified, spectroscopically characterized, and conformationally analyzed. Using experimental data, we discuss a possible mechanistic pathway for heterocyclization and evaluate the infl...

Human subjects consumed biscuits containing either galacto-oligosaccharides or fructo-oligosaccharides in a double-blinded, crossover study. The impact of supplementing the diet with three biscuits per day on the fecal microbiota was evaluated by selective culture of particular bacterial groups, measurement of beta-galactosidase activity, and nucleic acid-based analytical methods (PCR-denaturin...

The most conspicuous feature of the large-scale magnetic field in the Andromeda nebula (M31) is a magnetic belt centred at a galacto-centric radius of about 10 kpc. We suggest a nonlinear dynamo model for M31, which associates this belt with the gas density profile as well as with the kinematic parameters of M31. Our model is based on the observed density profile and vertical structure of the g...

The aim of this study was to investigate the effect of galacto-oligosaccharides, lactulose, apple fiber and sugar beet pectin on the composition and activity of human colonic microbiota of lean and obese healthy subjects using an in vitro model of the proximal colon: TIM-2. Substrate fermentation was assessed by measuring the production of short-chain and branched-chain fatty acids, lactate and...

An optimized noninvasive Raman microscope was used to evaluate tumor targeting and localization of single walled carbon nanotubes (SWNTs) in mice. Raman images were acquired in two groups of tumor-bearing mice. The control group received plain-SWNTs, whereas the experimental group received tumor targeting RGD-SWNTs intravenously. Raman imaging commenced over the next 72 h and revealed increased...

Molecular dynamics (MD) simulations were performed to investigate the adsorption behavior and dynamics of Arg-Gly-Asp (RGD) tripeptide onto the rutile TiO(2) (110) perfect and grooved surfaces in aqueous solution. The simulation results suggest that, driven by the electrostatic attractions between charged groups of the tripeptide and opposite-type charges of the surface atoms, RGD substitutes t...