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Major obstacles faced by the use of nonsteroidal anti-inflammatory drugs (NSAID) are their gastrointestinal toxicity induced by non-selective inhibition of both cyclooxygenases (COX) 1 and 2 and their cardiotoxicity associated with a certain class of COX-2 selective inhibitors. Recent studies have demonstrated that selective COX-1 and COX-2 inhibition generates compounds with no gastric damage. The aim of the current study is to develop novel anti-inflammatory agents with a better gastric profile. In our previous paper, we investigated the anti-inflammatory activity of 4-methylthiazole-based thiazolidinones. Thus, based on these observations, herein we report the evaluation of anti-inflammatory activity, drug action, ulcerogenicity and cytotoxicity of a series of 5-adamantylthiadiazole-based thiazolidinone derivatives. The in vivo anti-inflammatory activity revealed that the compounds possessed moderate to excellent anti-inflammatory activity. Four compounds 3, 4, 10 and 11 showed highest potency (62.0, 66.7, 55.8 and 60.0%, respectively), which was higher than the control drug indomethacin (47.0%). To determine their possible mode of action, the enzymatic assay was conducted against COX-1, COX-2 and LOX. The biological results demonstrated that these compounds are effective COX-1 inhibitors. Thus, the IC50 values of the three most active compounds 3, 4 and 14 as COX-1 inhibitors were 1.08, 1.12 and 9.62 μΜ, respectively, compared to ibuprofen (12.7 μΜ) and naproxen (40.10 μΜ) used as control drugs. Moreover, the ulcerogenic effect of the best compounds 3, 4 and 14 were evaluated and revealed that no gastric damage was observed. Furthermore, compounds were found to be nontoxic. A molecular modeling study provided molecular insight to rationalize the COX selectivity. In summary, we discovered a novel class of selective COX-1 inhibitors that could be effectively used as potential anti-inflammatory agents.

1,2,3-Triazole, a five-membered heterocyclic nucleus, is widely recognized as a key chromophore of great value in medicinal chemistry for delivering compounds possessing innumerable biological activities, including antimicrobial, antitubercular, antidiabetic, antiviral, antitumor, antioxidants, and anti-inflammatory activities. Mainly, in the past years, diverse conjugates carrying this biologically valuable core have been reported due to their attractive fungicidal potential and potent effects on various infective targets. Hence, hybridization of 1,2,3-triazole with other antimicrobial pharmacophores appears to be a judicious strategy to develop new effective anti-fungal candidates to combat the emergence of drug-sensitive and drug-resistant infectious diseases. Thus, the current review highlights the recent advances of this promising category of 1,2,3-triazole-containing hybrids incorporating diverse varieties of bioactive heterocycles such as conozole, coumarin, imidazole, benzimidazole, pyrazole, indole, oxindole, chromene, pyrane, quinazoline, chalcone, isoflavone, carbohydrates, and amides. It underlies their inhibition behavior against a wide array of infectious fungal species during 2015-2020.

Penicillin G is an old and widely used antibiotic. Its persistence in the environment started to appear in many environmental samples and food chains. The removal of these emerging pollutants has been a challenging task for scientists in the last decades. The photocatalytic properties of Cd2+ doped Manganese- Zinc NSFs with chemical formula (Mn0.5Zn0.5)[CdxFe2−x]O4 (0.0 ≤ x ≤ 0.05) NSFs are herein evaluated. The Manganese- Zinc N.S.F.s nanomaterials were deeply characterized, utilizing UV-Vis (reflectance) spectroscopy, X-ray diffraction, N2 adsorption isotherm measurements, and S.E.M., SEM-EDX mapping, and T.E.M. The Kinetic model for the photodegradation of penicillin G (as a model molecule) is investigated using visible light as a source of energy. The kinetic study shows that our results fit well with the modified pseudo-first-order model. The Pen G degradation are 88.73%, 66.65%, 44.70%, 37.62% and 24.68% for x = 0.5, 0.4, 0.3, 0.2 and 0.1, respectively, against 14.68% for the free Cd spinel sample. The pseudo-rate constant is bandgap dependent. From the intra-diffusion rate constant (Kd), we developed an intra-diffusion time (τ) model, which decreases exponentially as a function of (x) and mainly shows the existence of three different domains versus cadmium coordination in spinel ferrite samples. Hence, Cadmium’s presence generates spontaneous polarization with a strong opportunity to monitor the charge separation and then open the route to a new generation of “assisted” photocatalysts under visible light.

Background: Inflammation is a complex response to noxious stimuli promoted by the release of chemical mediators from the damaged cells. Metabolic products of arachidonic acid, produced by the action of cyclooxygenase and lipoxygenase, play important roles in this process. Several non-steroidal anti-inflammatory drugs act as cyclooxygenase inhibitors. However, almost all of them have undesired side effects. Methods: Prediction of the anti-inflammatory action of the compounds was performed using PASS Program. The anti-inflammatory activity was evaluated by the carrageenan paw edema test. COX and LOX inhibitory actions were tested using ovine COX-1, human recombinant COX-2 and soybean LOX-1, respectively. Docking analysis was performed using Autodock. Results: All designed derivatives had good prediction results according to PASS and were synthesized and experimentally evaluated. The compounds exhibited in vivo anti-inflammatory action with eleven being equal or better than indomethacin. Although, some of them had no or low inhibitory effect on COX-1/2 or LOX, certain compounds exhibited COX-1 inhibition much higher than naproxen and COX-2 inhibition, well explained by Docking analysis. Conclusions: A number of compounds with good anti-inflammatory action were obtained. Although, some exhibited remarkable COX inhibitory action this activity did not follow the anti-inflammatory results, indicating the implication of other mechanisms.

SSCI-VIDE+CARE:ECI2D+MHM:GBE:FDA:CGU:HKO; International audience; The influence of polyhydroxyfullerene (PHF) on the photocatalytic properties of calcined hydrogenotitanate nanotubes (HNT) were evaluated in the present study. PHF-HNT nanocomposites were first characterized by N-2 adsorption-desorption measurements, X-ray diffraction, X-ray photoelectron, electron paramagnetic resonance and UV vis diffuse reflectance spectroscopies, transmission electron microscopy, photoluminescence, and photocurrent experiments. Correlation was then established with the photocatalytic properties of PHF-HNT nanocomposites during the photodegradation of formic acid. (C) 2017 Elsevier B.V. All rights reserved.

This paper builds on previous literature showing the interesting adsorptive properties of TiO2 nanotubes. It further explores the positive effect of β-cyclodextrin on these properties. Hence, β-cyclodextrin modified TiO2 nanotubes were successfully prepared and characterized by XRD, N2 physisorption at 77 K, Raman, FTIR-ATR, 1H NMR, TEM and EPR. The adsorptive interaction of Cu(II) with materials was investigated in aqueous solution at pH 9.25 (NH4+/NH3). The main conclusion is that copper(II)-ammonia complexation equilibria play an important role in the adsorption process. The β-cyclodextrin was found to improve the Cu(NH3)42+ adsorption mainly by retarding its precipitation to high concentrations values (>400 mg L−1). Adsorption experimental data showed good fit with the pseudo-second-order model and the Langmuir isotherm model.

Background: Inflammation is a complex response to noxious stimuli promoted by the release of chemical mediators from the damaged cells. Metabolic products of arachidonic acid, produced by the action of cyclooxygenase and lipoxygenase, play important roles in this process. Several non-steroidal anti-inflammatory drugs act as cyclooxygenase inhibitors. However, almost all of them have undesired side effects. Methods: Prediction of the anti-inflammatory action of the compounds was performed using PASS Program. The anti-inflammatory activity was evaluated by the carrageenan paw edema test. COX and LOX inhibitory actions were tested using ovine COX-1, human recombinant COX-2 and soybean LOX-1, respectively. Docking analysis was performed using Autodock. Results: All designed derivatives had good prediction results according to PASS and were synthesized and experimentally evaluated. The compounds exhibited in vivo anti-inflammatory action with eleven being equal or better than indomethacin. Although, some of them had no or low inhibitory effect on COX-1/2 or LOX, certain compounds exhibited COX-1 inhibition much higher than naproxen and COX-2 inhibition, well explained by Docking analysis. Conclusions: A number of compounds with good anti-inflammatory action were obtained. Although, some exhibited remarkable COX inhibitory action this activity did not follow the anti-inflammatory results, indicating the implication of other mechanisms.

Selective adsorption of La, Ce, Y and Nd rare earth elements (REEs) from aqueous solution was performed using TiO2 nanotubes. Kinetic study reveals that REEs adsorption on TiO2 nanotubes is highly enhanced at pH 5 (acetate buffer). The experimental parameters keys such as pH, eluent concentration and flow rate are investigated. The desorption of REEs prior to ICP analysis is also studied. From thermodynamic study, the adsorption heats, are REEs atomic radius dependent, which opens a new route for the selective separation. An engineered packed column with TiO2 nanotubes was used under continuous flow for the REEs extraction. Our method yields excellent recovery (> 98%) of REEs, and the column can be regenerated up to 20 cycles.

An interesting adsorption capacity for TiO2 nanotubes has been demonstrated in this work using penicillin G (PEG), as the antibiotic model. Isotherms and kinetic studies revealed that PEG adsorptio...

AIR:EAU:RAFFINAGE:MATERIAUX+ATR:HKO:CGU:GBE; The influence of the sodium content on thermal stability and photocatalytic activity of calcined titanate nanotubes (TNT) was herein evaluated by preparing different samples through hydrothermal treatment of TiO2 powder (P25) in a concentrated NaOH solution (11.25 M) at 130 degrees C during 20 h followed by acid washing steps. Titanate nanotubes samples with sodium (Na-TNT) and sodium-free (H-TNT) were then obtained using different concentrations of HCI aqueous solutions namely 0.1 M and 1 M respectively. As synthesized nanomaterials with different Na percentages were then calcined at temperatures varying between 400 degrees C and 700 degrees C. Samples were characterized by means of nitrogen adsorption-desorption isotherms at 77 K, thermal analysis (DTA, TGA), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and diffuse reflectance spectroscopy (DRS). The photocatalytic activities of Na-TNT and H-TNT derived nanomaterials were then evaluated through the photocatalytic degradation of formic acid (FA). Results show that the presence of sodium retards the dehydration process during the transformation of titanate into TiO2 shifting the formation of anatase phase to higher temperatures. However, sodium is not necessary to preserve the nanotubular morphology. The presence of sodium after calcination strongly impacts negatively the photocatalytic properties. If sodium is completely removed from the initial titanate orthorhombic phase, calcination leads to TiO2 anatase materials with enhanced photocatalytic properties compared to P25 in the degradation of formic acid, particularly if nanotubular morphology is preserved. The highest activity was therefore achieved for the H-TNT sample calcined at 400 degrees C. The photodegradation activity of formic acid depends on the specific surface areas and TiO2 crystallinity. In pure anatase nanoparticles the activity strongly decreases with coherent crystallographic domains >= 10 nm. (c) 2013 Elsevier B.V. All rights reserved.

Titanium dioxide nanotubes were prepared via a hydrothermal treatment of TiO 2 powder (Degussa P25). Obtained samples were analyzed by various techniques, such as transmission electron microscopy (TEM) and X-ray diffraction (XRD), which revealed that the crystal structure of the obtained materials was similar to that of H 2 Ti 2 O 5 ·H 2 O nanotubes, and were about 50 nm in length and 20 nm in diameter. Nitrogen adsorption–desorption isotherms indicated that synthesized solids are mesoporous materials with a multi-walled nanotubular structure and high specific surface area. The methanol oxidation reaction was investigated on platinum nanoparticles supported TiO 2 nanotubes (XC72). The electrocatalytic activity of the catalyst was measured by cyclic voltammetry. CO stripping voltammetry in acidic solutions was investigated to study the reaction of the catalysts towards poisoning by carbonyl compounds. The results demonstrated that Pt/TiO 2 nanotubes catalyst exhibits the best activity for methanol oxidation and were favorable for improving the tolerance to poisoning species.

Mesostructured TiO2 nanomaterials with tuned crystallite sizes were elaborated by a novel green route using soluble starch as the structuring agent and titanium(IV) isopropoxide as the inorganic pr...

Bimetallic Au–Pd clusters were successfully elaborated by selective deposition over citrate-functionalized TiO2 nanocrystallites. Anisotropic gold nanoparticles are obtained by adjusting the Pd/Au ...

Nanostructured palladium particles (nanorods, icosahedra, cubes) were synthesized in aqueous solution using a seeding-mediated approach with a structure-directing agent. These nanostructured Pd particles were then impregnated onto hydrogenotitanate nanotubes using two different impregnation procedures. The as-prepared catalysts were then tested in the selective hydrogenation of cinnamaldehyde at 323 K under 10 bars of H2. The selectivity is influenced by the morphology of the Pd nanostructured particles with a higher selectivity into saturated alcohols when the proportion of (111) Pd sites increases.

International audience; A novel and easy synthesis route to mesoporous nanocrystalline TiO2 samples using soluble starch as the structural agent and mainly titanium(IV) isopropoxide as the inorganic precursor was described. The effect of key parameters, including soluble starch removal process, the solvent nature and the type of titanium precursor were discussed. Using soluble starch in cyclohexane as non polar solvent, a surface area of 94 m2.g−1 associated with 23 nm crystallites size was obtained. TiO2 samples were characterized by means of N2 adsorption-desorption, X-ray Diffraction (XRD), TG-DTA, Scanning Electron Microscopy (SEM) and ATR-FTIR spectroscopy.

A thioresistant NOx trap based on CuO supported on sulphated zirconia mixed with a solid base is described. The rate of adsorption of NO at constant temperature and the amount of NO retained from a feed containing 750 ppm NO, 10% O2 and 5% water in nitrogen were measured. On badly dispersed CuO, the capacity for NOx adsorption does not decrease but slightly increases in the presence of 25 ppm SO2 in the feed. By contrast, a well dispersed Cu catalyst is irreversibly poisoned. The surface nitrates can be decomposed in air at 623 K. In a mixture, Ar + 1% H2, the nitrate is partly reduced to N2 at about 630 K, even after operation in the presence of SO2. The catalyst does not lose adsorption capacity after 10 cycles of adsorption–desorption and can be used in the temperature range 473–773 K. The resistance to SO2 depends also in part of the properties of the solid base.

The isomerization of styrene oxide has been investigated on mixed oxides obtained by calcination of hydrotalcites, rare earth phosphates and KF supported on alumina. All solids form β-phenylacetaldehyde. Basic catalysts deactivate rapidly or show a lower selectivity, most probably due to the formation of heavy products by aldolisation. ZnAl catalyst shows a selectivity towards β-phenylacetaldehyde >98% with no deactivation after 7 h on stream, in a flow gas phase process at 423 K.

Oxidation of primary hydroxyl groups of potato starch to the corresponding carboxylic acids was performed in a fluidized bed using N2-diluted NO2 as oxidant. FT-IR spectrum of the oxidized starch show the presence of two absorption bands at 1743 and 1379 cm−1. The absorption at 1743 cm−1 which normally attributed to carbonyl absorption vanishes after washing the oxidized starch by water. Then two new absorption bands appeared at 1650 and 1400 cm−1 corresponding to the ionized carboxyl groups. The presence of nitrate favor the un-ionized form of carboxyl groups and then the band at 1743 cm−1 can be observed. Furthermore, the ionized carboxyl absorption (1600, 1400 cm−1) are replaced by carbonyl absorption at 1743 cm−1 by adding DCl. By means of 13C NMR analysis, oxidized starch, show a band around 200 ppm attributed to carboxylic acid, no formic acid was detected indicating that no cleavage took place under the applied reactions conditions.

Primary hydroxyl groups were oxidized regioselectively to carboxylic acid using organic nitrosonium salts generated on supported silver catalysts, which promote disproportionation of 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) in aqueous solution. The oxidation reactions were performed at pH 9.5 in a batch reactor at room temperture using heterogeneous silver catalysts and peroxides as primary co-oxidants; e.g., 99 mol% selectivity to methyl-α-D-glucopyrasiduronic acid was obtained at 90% conversion of the pyranoside using a silver carbonate–celite catalyst . The efficiency of the system was increased by adding carbonates to the silver catalyst. This result is explained by the increase of the electron charge deficiency on silver in the presence of carbonate, which accelerates the nucleophilic attack of hydroxyls and/or TEMPO. In the case of the Ag–Al2O3 catalyst, this result was proved by temperature-programmed desorption measurements using ammonia. With primary/secondary polyols, the selectivity for the primary hydroxyl groups is high. In addition, primary hydroxyl groups, as in the case of pyranosides, were oxidized more selectively than those of the furanosides. The observed regioselectivity is due to the sterical hindrance caused by the four methyl groups in TEMPO.

Hydrophobic mesoporous titano-silicates (HyMTS) have been prepared at ambient temperature by a sol–gel technique using hexadecyl-trimethyl-ammonium chloride in acid medium as templating surfactant. The gellation time increases for low reaction temperatures and low H + /Si ratios. The amorphous materials thus obtained at long gellation times show hydrophobic properties and a lower number of OH bearing Si atoms as determined from 29 Si MAS NMR. In the epoxidation of norbornene with H 2 O 2 or of cyclohexene with tert-butyl hydroperoxide, HyMTS reaches selectivities for the epoxide of 95% or higher. The epoxidation of cyclohexene by H 2 O 2 also gives better selectivities to the epoxide on these hydrophobic samples, compared to hydrophilic solids. It is suggested that hydrophobicity results from the slow kinetics of gellation.

Shape-controlled Ag and Pd nanocrystals were synthesized using seed-mediated techniques using β-cyclodextrin (β-CD) as structuring agent. First, seeds were obtained by reacting Na2PdCl4 or AgNO3 with a strong reducing agent, NaBH4 in the presence of sodium citrate dihydrate acting as stabilizing agent. These seeds were then injected into a growth solution containing the same metallic precursor, ascorbic acid (as a weak reducing agent) and β-CD as structuring agent. TEM results emphasize a strong influence of the relative concentration of β-CD on the final morphology. In the case of silver, well-facetted nanocrystals were obtained with a progressive shift from kinetically to thermodynamically-controlled nanoobjects when increasing the β-CD/Ag molar ratio. On palladium, β-CD leads to the formation of dendrites (urchin-like) or multipods through controlled aggregation of primary particles. The use of β-CD does not interfere negatively with the catalytic properties of the Pd nanocrystals in the hydrogenation of cinnamaldehyde.

1 D TiO2 nanomaterials (nanotubes, nanowires) were synthesized through hydrothermal treatment of TiO2 powder (P25) in concentrated alkaline solutions (NaOH for nanotubes, KOH for nanowires) followed by calcination at varying temperatures between 400°C and 700°C. Samples were characterized by HRTEM, XRD, Raman spectroscopy, and N2 adsorption-desorption isotherms. High surface area nanotubular TiO2 materials can maintain their 1D morphology up to a temperature of calcination of 400°C while changing their phase from hydrogenotitanate to anatase. The use of KOH leads to a retarded formation of anatase. Photocatalytic results showed that TiO2 anatase nanotubes calcined at 400°C can degrade formic acid with a rate constant four times higher than for P25. A direct correlation between surface area and photocatalytic activity explains the much higher activity of TiO2 anatase nanotubes. On the opposite, for the degradation of phenol, P25 remains more active. In the disinfection of water, contrary to P25, the high surface area of TiO2 nanotubes allows the simultaneous degradation of formic acid and the inactivation of pathogen fungus showing the interest of such materials for the treatment of wastewater.

EAU:RAFFINAGE:MATERIAUX+AME:HKO:SDA:VME:GBE; One-pot deposition of Pd onto TiO2 has been achieved through directly contacting palladium(II) salt with nanosized functionalized TiO2 support initially obtained by 501-gel process using titanium isopropoxide and citric acid. Citrate groups act as functional moieties able to directly reduce the Pd salt avoiding any further reducing treatment. Various palladium salts (Na2PdCl4 and Pd(NH3)(4)Cl-2 center dot H2O center dot H2O) and titanium to citrate (Ti/CA) ratios (20, 50, and 100) were used in order to study the effect of the nature of the precursor and of the citrate content on the final Pd particle size and catalytic properties of the as-obtained Pd/TiO2 systems. Characterization was performed using N-2 adsorption-desorption isotherms, ICP-AES, FTIR, XRD, XPS, and TEM. The as-obtained hybrid Pd/TiO2 catalysts were tested in the selective hydrogenation (HYD) of an m,alpha beta-unsaturated aldehyde, i.e. cinnamaldehyde. Citrate-free Pd/TiO2-based catalysts present lower selectivity into saturated alcohol. However, citrate-functionalized Pd/TiO2 catalyst seems to control the selectivity, the particle size and dispersion of Pd NPs leading to high intrinsic activity. (C) 2011 Elsevier Inc. All rights reserved.

An analytical method based on TiO2 nanotubes solid-phase extraction (SPE) combined with gas chromatography (GC) was established for the analysis of seven polycyclic aromatic hydrocarbons (PAHs): acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 microg/mL, repeatability of the extraction (RSD were between 6.7% and 13.5%, n = 5) and satisfactory detection limits (0.017-0.059 ng/mL). The developed method was successfully applied to the analysis of surface water (tap, river and dam) samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.

One-pot deposition of Pd onto TiO 2 has been achieved by direct impregnation in excess of Na 2 PdCl 4 contacted with citrate-functionalized TiO 2 support initially obtained by sol-gel process techniques using Ti(O i Pr) 4 and citric acid. Citrate groups act as functional moieties able to directly reduce the Pd salt avoiding any further reducing treatment. Various titanium to citrate (Ti/CA) ratios (20, 50, and 100) were used to prepare the hybrid TiO 2 support in order to study the effect of citrate on the final catalytic properties of Pd/TiO 2 catalysts. Characterizations were performed using N 2 adsorption-desorption, ICP-AES, FTIR, XRD, XPS, and TEM. The as-obtained Pd/TiO 2 catalysts were tested in the selective hydrogenation (HYD) of cinnamaldehyde. Using citrate-functionalized TiO 2 support increases both the activity and the selectivity to saturated alcohol.

Palladium nanoparticles (NPs) with well-controlled morphologies (cubes, rods, icosahedra) and with preferential crystallographic planes were prepared through a seed-mediated colloidal approach. Pd NPs were then impregnated onto high surface area hydrogenotitanate nanotubes before being evaluated in the selective hydrogenation of a α,β-unsaturated aldehyde, i.e. cinnamaldehyde. Their preferential exposition of crystallographic planes (mainly (100) and (111) sites) offers the unique ability to determine the influence of the structure-sensitivity of this selective hydrogenation reaction in real experimental conditions. Results show that the selectivity to saturated alcohol increases with increasing proportion of Pd(111) sites.

Pd- and Fe/Pd-HNT were elaborated by successive ionic exchange and wet impregnation at room temperature of hydrogenotitanate nanotubes (HNT) nanomaterials. Hydrogen peroxide was generated in situ via reaction of oxygen and formic acid (FA) over Fe/Pd-HNT catalysts. A high p-hydroxybenzoic acid (p-HBz) mineralization was achieved (52%) using Fe/Pd-HNT/FA/O2/UV system compared to the simulated reaction using Fe/Pd-HNT/H2O2/UV system (34%). The rate of hydrogen peroxide formation over Pd-HNT catalyst, during in situ generation, probably plays a key role in controlling the kinetics of the p-HBz degradation.

Mesoporous nanocrystalline TiO2 samples were prepared in the presence of various structural agents. Our approach involves the co-assembly of ionic surfactant or neutral soluble starch and titanium (IV) isopropoxide under mild reaction conditions. Small crystallites sizes of 23 nm were successfully obtained in non-polar solvent such as cyclohexane. Several methods were used to remove surfactants and their effect on the porous structure and surface area were compared. Soluble starch leads to mesoporous samples and enhances their thermal stability due to an increase in the wall thickness up to 10 nm.

Primary hydroxyl groups were oxidized regioselectively using organic oxoammonium salts generated on supported silver catalysts, which promote disproportionation of 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) in aqueous solution. The oxidation reactions were performed at pH 9.5 in a batch reactor at RT using heterogeneous silver catalysts and peroxides as primary co-oxidants. 99 mol.% selectivity to methyl-α-D-glucopyrasiduronic acid was obtained at 90% conversion of the pyranoside over a silver-celite catalyst. The activity was increased by adding carbonates to the silver catalysts. This result can be explained by the increase of the electron charge deficiency on silver in presence of carbonate, which accelerates the nucleophilic attack of TEMPO and/or hydroxyl groups. This result was proved using TPD of ammonia in the case of Ag-Al2O3 catalyst. The observed regioselectivity is due to the sterical hindrance caused by the four methyl groups in TEMPO.