Search

Within the present study, novel chelating resins containing a layer loaded with N-methyl-D-glucamine functionalities were synthesized. The procedure involved impregnation of macroporous Amberlite XAD-4 adsorbent using mixture of vinylbenzyl chloride (VBC) and divinylbenzene (DVB) further subjected to free radical suspension polymerization. The so-obtained 1PTN and 2PTN adsorbents were characterized by expanded-gel or microporous structure of VBC-co-DVB layer, respectively. The both materials were used in desalination of geothermal water aimed to decrease levels of boron and arsenic. As a part of this, he research on boron and arsenic removal included batch adsorption and kinetic studies. The results have shown that the resin 1PTN showed maximum boron removal of 64% and arsenic removal of 18% from the geothermal water. The resin 2PTN exhibited competitive boron removal performance as compared to the commercial Diaion CRB 05 resin, reaching its efficiency by removing over 96% of boron. Also, the sample 2PTN outmatched Diaion CRB 05, removing 97% of arsenic and leading to decrease of its concentration to permissible level., bilateral collaboration program between Turkey and Poland [TUBITAK-NCBR-2549, TuBTAK 117M023]; Turkish Higher Education CouncilMinistry of National Education - Turkey [YoK 100-2000], This research has been financially supported by bilateral collaboration program (TUBITAK-NCBR-2549) between Turkey and Poland (Project No: TuBTAK 117M023).; E. Altok is grateful for the PhD scholarship of Turkish Higher Education Council (YoK 100-2000). We thank Izmir Geothermal Co. for the kind support to get geothermal water samples. We also acknowledge Mitsubishi Chem. Japan for Diaion CRB 05 resin.

The N-methyl-D-glucamine moieties exhibit high ability and selectivity toward arsenate ions in water by a complexation mechanism that involves their hydroxyl groups. In this work, the syntheses of two monomers containing N-methyl-D-glucamine, namely 4-vinylbenzyl-N-methyl-D-glucamine (VbNMDG), and N-methyl-D-glucamine methacrylamide (MNMDG) were studied. Different synthetic routes were considered in order to obtain liquid monomers able to polymerize and selectively capture arsenic. Furthermore, the incorporation of protective groups like trimethylsilyl moieties in the molecular structure was assessed to prevent transfer reactions during further polymerization. After polymerization, hydroxyl groups were deprotected using hydrofluoric acid. Following this methodology, structured microporous polymeric films based on colloidal crystal templates were prepared. NMR and FTIR techniques were used to follow the reactions and to determine the chemical structure of the obtained products. The morphology of materials was characterized by SEM. The performances of the developed polymeric films to selectively capture arsenic were determined. Films showed an improved and reproducible sensitivity to arsenic detection exhibiting high values of arsenic capturing capability (around 90%).

Glycidyl methacrylate (GMA) was grafted onto the surface of HDPE particles by radiation grafting and emulsion graft copolymerization. And subsequent ring-opening reaction of expoxy groups in poly-GMA graft chains with N-methylglucamine (NMG) was conducted to synthesis the boron adsorbent. The synthesis condition (radiation dose and NMG concentration) was optimized and characterized by IR and SEM. Adsorption behaviors of the boron adsorbent for boron removal presented that adsorption kinetics was well described by pseudo-second-order kinetic mode. The adsorption isothermal was well fitted with both Langmuir and Freundlich isotherm models. The adsorption capacity for boron reached 15.63 mg/g at optimal pH 8. Dynamic experiment revealed that boron could be efficiently adsorbed by the boron adsorbent and fully desorbed using 13 BV of 1 mol/L HCl.

The facile reaction of a readily available aminopolyol from the chiral pool, N-methyl- d -glucamine, which avoids the side reactions usually associated to anomers of amino sugars, with epoxide and polyepoxide derivatives, enables the preparation of new non-ionic surfactant-like structures combining hydrophilic and hydrophobic moieties. The molecular architectures thus obtained range from linear to tripodal and pyramidal structures. The resulting substances containing multiple chiral centers exist as diastereomeric mixtures, for which various conformations are likewise possible by virtue of inter-chain interactions. The stability and chirality preferences of all possible stereoisomers have been evaluated in detail by DFT methods. Given the amphiphilic structure of both protected and O-protected derivatives obtained by acetylation, self-aggregation could eventually lead to solvent entrapment. Unfortunately, only one compound behaves as efficient hydrogelator and DMSO-gelator at low concentrations. The issue is also discussed in terms of the different molecular arrangements.

In this research, a series of one-dimensional controllable crosslinked polymers with the different mass ratios of 4-vinylbenzychloride (VBC) and divinyl benzene (DVB) was prepared via cationic polymerization, and the polymers were grafted with the functional group N-methyl-D-glucamine (NMDG) for boron removal. The optimum polymeric mass ratio and a series of boron adsorption performances were studied. The maximum adsorption capacity was 18.15 mg g−1, of which 94% was retained after 4 cycles. Meanwhile, different pH values had negligible effect on the boron adsorption capacity, which was favorable for the removal of boron from its aqueous solution in a wide pH window. In addition, a magnetic adsorbent was prepared by the combination of Fe3O4 nanoparticles and the polymer, which provided an effective way to collect and recover adsorbents from their aqueous solutions.

Reaction of available derivatives of 1-acylamino-2,2-dichloroacrylic acids as well as diethyl esters of 1-acylamino-2,2,2-trichloroethylphosphonic acids with N-methyl-D-glucamine furnished previously unknown 1,3-oxazole derivatives containing nitrile, ester or phosphonyl groups in the position 4 and N-methyl-D-glucamine residue in the position 5.

This protocol is a practical guide to the N-methyl-D-glucamine (NMDG) protective recovery method of brain slice preparation. Numerous recent studies have validated the utility of this method for enhancing neuronal preservation and overall brain slice viability. The implementation of this technique by early adopters has facilitated detailed investigations into brain function using diverse experimental applications and spanning a wide range of animal ages, brain regions, and cell types. Steps are outlined for carrying out the protective recovery brain slice technique using an optimized NMDG artificial cerebrospinal fluid (aCSF) media formulation and enhanced procedure to reliably obtain healthy brain slices for patch clamp electrophysiology. With this updated approach, a substantial improvement is observed in the speed and reliability of gigaohm seal formation during targeted patch clamp recording experiments while maintaining excellent neuronal preservation, thereby facilitating challenging experimental applications. Representative results are provided from multi-neuron patch clamp recording experiments to assay synaptic connectivity in neocortical brain slices prepared from young adult transgenic mice and mature adult human neurosurgical specimens. Furthermore, the optimized NMDG protective recovery method of brain slicing is compatible with both juvenile and adult animals, thus resolving a limitation of the original methodology. In summary, a single media formulation and brain slicing procedure can be implemented across various species and ages to achieve excellent viability and tissue preservation.

A one-pot procedure for preparing chiral 1,3-oxazolidines derived from N-methyl-d-glucamine and aryl aldehydes is described. It has been carried out by using readily available reagents and operationally simple conditions allowing the preparation of the acyclic C-nucleoside analogs in high yields. The structure of these derivatives has been fully characterized by NMR correlations and single-crystal X-ray diffraction. Some reactions also provide access to the corresponding tetrahydro-1,3-oxazines by an alternative ring closure. Mechanistic considerations account for the observed steric course.

It is well known that adsorbents having N-methyl-D-glucamine (NMDG) preferentially adsorb boron. The boron adsorbent developed in this study has promising properties of rapid boron adsorption from the natural water. The adsorbent was prepared by radiation induced graft polymerization of glycidyl methacrylate (GMA) onto non-woven polyethylene fabrics in aqueous medium, and following chemical modification with NMDG The resulting adsorbent was evaluated by column-mode adsorption of boron at various flow rates. Comparison between graft adsorbent and granular resin, graft adsorbent has 4 times higher bed volume (BV) at breakthrough point at space velocity (SV) 50 h-1. The BV at breakthrough point of graft adsorbent at SV 100 h-1 gave the same one with granular resin at SV10 h-1.

N-Methyl-d-glucamine (NMDG) immobilized onto cross-linked poly(vinylbenzyl chloride) beads is found to have a high affinity and selectivity for Hg(II) from nitric and hydrochloric acid solutions. In HNO3, complexation is >98% from a solution at pH 3, which decreases to 11.2% from 1 M HNO3. Hg(II) is complexed to a greater extent from HCl: 95.4% is complexed from 1 M HCl and >99.5% from solutions at pH 1.0 and greater. Control studies with immobilized sorbitol show that coordination of Hg(II) by the -OH groups is an important component of the mechanism. Complexation by sorbitol is dependent on the pH. Log−log plots of the distribution coefficients versus the hydrogen ion concentration at equilibrium show the importance of the changing nature of the solution species: since ion exchange is not mechanistically possible with sorbitol, the pH dependency reflects the effect of pH on shifting the species in solution from noncoordinating Hg(NO3)42- and HgCl42- to coordinating Hg(NO3)+ and HgCl2. Comparison to re...

The resin poly[N-(4-vinylbenzyl)-N-methyl-d-glucamine] [P(VbNMDG)] was synthesized and its performance for Cr(VI) removal was studied. This resin presented a very fast kinetic of Cr(VI) sorption following a pseudo-second order. Also, the rate-controlling step of Cr(VI) sorption performed by film diffusion in accordance with infinite solution volume model and reacted layer in accordance with unreacted core model. The column study showed a breakthrough capacity of 12.2 mg Cr/mL-resin, with an elution efficiency of 92 %. Mechanism of sorption could correspond to an electrostatic interaction followed by a complexation reaction.

Activation of membrane P2X7 receptors by extracellular ATP [or its analog 2′,3′- O-(4-benzoylbenzoyl)-ATP] results in the opening within several milliseconds of an integral ion channel that is permeable to small cations. If the ATP application is maintained for several seconds, two further sequelae occur: there is a gradual increase in permeability to the larger cation N-methyl-d-glucamine and the cationic propidium dye quinolinium, 4-[(3-methyl-2(3 H)-benzoxazolylidene)methyl]-1-[3-(triethylammonio)propyl]diiodide (YO-PRO-1) enters the cell. The similarity in the time course of these two events has led to the widespread view that N-methyl-d-glucamine and YO-PRO-1 enter through a common permeation pathway, the “dilating” P2X7 receptor pore. Here we provide two independent lines of evidence against this view. We studied single human embryonic kidney cells expressing rat P2X7 receptors with patch-clamp recordings of membrane current and with fluorescence measurements of YO-PRO-1 uptake. First, we found that maintained application of the ATP analog did not cause any increase in N-methyl-d-glucamine permeability when the extracellular solution contained its normal sodium concentration, although YO-PRO-1 uptake was readily observed. Second, we deleted a cysteine-rich 18-amino acid segment in the intracellular juxtamembrane region of the P2X7 receptor. This mutated receptor showed normal YO-PRO-1 uptake but had no permeability to N-methyl-d-glucamine. Together, the clear differential effects of extracellular sodium ions or of mutation of the receptor strongly suggest that N-methyl-d-glucamine and YO-PRO-1 do not enter the cell by the same permeation pathway.

beta-N-tert-butyloxycarbonyl-N-carboxyanhydrides are very reactive beta-amino acid derivatives. They react cleanly and smoothly with different nucleophiles like aminoesters, enolates, N-methyl-d-glucamine, amidoximes to afford in good to excellent yields peptides, beta-amino ketocompounds, beta-aminosugars and functionalized disubstituted 1,2,4-oxadiazoles.

Some aspects of the measurement of alkaline phosphatase activity concentration in human serum, using N-methyl-D-glucamine as a buffer, were evaluated with a view to the possible routine use of the method. The evaluated characteristics included: the temperature-dependence of the pH of the buffer; the effect of adding the magnesium/zinc ions buffer; the effect of the serum volume fraction; the substrate-starter versus the serum-starter mode; the effect of modifying the formulation of reagents; the within-run and the between laboratory imprecision; the correlation with an alternative routine method. Also, sex- and age-related reference values were produced, based on 2968 values from selected reference sample groups in 7 laboratories. In general, the results demonstrate the robustness of the method, its adaptability to a variety of mechanized analysers, and hence its feasibility as a routine measurement method.

In a double-blind trial 40 patients with ostheoarthritis were treated for relief of pain with ketoprofen or with the N-methyl-d-glucamine salt of indomethacin, both drugs being administered i.m. at the dosage of 100 mg/day for 12 days. Ketroprofen and the indomethacin salt significantly improved pain, functional capacity and walking distance, while only the former reduced the knee size in the patients with gonarthritis. The two drugs showed roughly the same latency period and the same duration of activity. Ketoprofen was perfectly tolerated: on the contrary, in one patient treated with the indomethacin salt, the treatment was stopped because of vascular hypotension and cutaneous rash. A significant increase of blood urea nitrogen was observed only in the group of patients treated with the indomethacin salt.

We describe a method for determining serum alkaline phosphatase activity with use of N-methyl-D-glucamine buffer, Na+ is a definite activator, whereas NH4+ and Li+ inhibit enzyme activity. Optimum reaction conditions are: methylglucamine buffer, 0.35 mol/L, pH 10.2 +/- 0.1 (30 degrees C); NaCl, 70 mmol/L; MgCl2, 0.5 mmol/L; disodium 4-nitrophenyl phosphate, 15 mmol/L; reaction temperature, 30 degrees C; reaction time, 2 min. The assay conditions are optimum for all human serum isoenzymes.

Methylglucamine is a commonly used cation in radiocontrast media. The present study sheds light on its fate in the rat. When administered intraperitoneally, 93% of the compound was excreted unchanged in the urine in 24 hr. When administered orally, about 15% of the dose was found in the urine, about 40% in the faeces and 20% in expired air in 24 hr. When administered orally to rats whose gut flora had been depleted by treatment with neomycin sulphate, 19% was excreted in the urine, 69% in the faeces and 3% in expired air in 72 hr. This indicated that the gut flora played a role in the degradation of the compound and its eventual loss as expired carbon dioxide.