Search results for "BD"
showing 10 items of 3363 documents
Synthesis, Structure and Catalytic Properties of Dinuclear Mo-VI Complexes with Ditopic Diaminotetraphenols
2013
MoVI complexes with novel ditopic diaminotetraphenol ligands have been prepared by using a one-pot procedure in methanol or DMSO with [MoO2(acac)2] (acac = acetylacetonate) as the molybdenum source. The complexes were characterised with X-ray diffraction, NMR spectroscopic studies, elemental analysis and IR spectroscopy. In the solid state, the compounds represent either a rodlike molecular or oxido-bridged polymeric structure. The catalytic activity of the complexes was investigated by oxidising benzyl alcohol and 1-phenylethanol with hydrogen peroxide to the corresponding aldehyde and ketone, respectively. Furthermore, the catalytic activity was surveyed also in epoxidation of cyclooctene.
Improved Preparations of Molybdenum Coordination Compounds from Tetrachlorobis(diethyl ether)molybdenum(IV)
2001
International audience; The reduction of MoCl5 with metallic tin in diethyl ether provides a rapid and convenient entry to [MoCl4(OEt2)2] This compound can be transformed easily and in high yields into a variety of other useful synthons. The loss of ether in the solid state affords a new and reactive form of MoCl4. Treatment with THF, PMe3 or LiOtBu affords [MoCl4(THF)2], [MoCl4(PMe3)3] or [Mo(OtBu)4] in high isolated yields. Treatment with metallic tin in THF affords [MoCl3(THF)3] All of these reactions can be carried out under simple experimental conditions and represent significant improvements relative to previously reported syntheses of the same compounds.
Functional end groups for polymers prepared using ring-opening metathesis polymerization.
2011
The precise placement of functional groups on the chain-ends of macromolecules is a major focus of polymer research. Most common living polymerization techniques offer specific methods of end-functionalization governed by the active propagating species and the kinetics of the polymerization reaction. Ring-opening metathesis polymerization has established itself as one of the most functional-group-tolerant living polymerization techniques known, but this tolerance has limited the number of available functionalization reactions. Metathesis chemists have therefore been required to develop a variety of end-functionalizations, adapting each of them to the reactivity scheme of the particular cata…
Electrochemical Oxidation of Carboxylic Acids in Water at Boron-Doped Diamond (BDD) Anodes in the Range of Potential of Oxygen Evolution: Detection M…
2013
The electrochemical oxidation in water solutions of selected carboxylic acids (namely oxalic, formic, acetic, maleic, and succinic) at boron-doped diamond (BDD) anodes was investigated by polarization and chronoamperometric measurements. In the presence of low concentrations of carboxylic acids, current densities changed approximately linearly with the acid concentrations. Furthermore, when the current densities were plotted as a function of the chemical oxygen demand, a similar response was observed for all the investigated acids with the exception of oxalic acid. For high carboxylic acid concentrations, the linear variation is often loosen and different behaviors are observed depending on…
Digestion and absorption of polyunsaturated fatty acids
1991
Polyunsaturated fatty acids play an important part in the structure and function of cellular membranes and are precursors of lipid mediators which play a key role in cardiovascular and inflammatory diseases. Dietary sources of essential fatty acids are vegetable oils for either linoleic or alpha-linolenic acids, and sea fish oils for eicosapentaenoic and docosahexaenoic acids. Because of the specificity of the pancreatic lipid hydrolases, triglyceride fatty acid distribution is an essential parameter in the digestibility of fats. The efficiency of the intestinal uptake depends on the hydrolysis and especially on their micellarization. n-3 polyunsaturated fatty acid ethyl ester digestion is …
Translational adaptation to heat stress is mediated by 5-methylcytosine RNA modification in Caenorhabditis elegans
2020
ABSTRACTMethylation of carbon-5 of cytosines (m5C) is a post-transcriptional nucleotide modification of RNA found in all kingdoms of life. While individual m5C-methyltransferases have been studied, the impact of the global cytosine-5 methylome on development, homeostasis and stress remains unknown. Here, usingCaenorhabditis elegans, we generated the first organism devoid of m5C in RNA, demonstrating that this modification is non-essential. We determined the localisation and enzymatic specificity of m5C sites in RNAin vivoand showed that animals devoid of m5C are sensitive to temperature stress. At the molecular level, we showed that loss of m5C specifically impacts decoding of leucine and p…
Propane-1,3-diammonium molybdate
2019
The reaction between equimolar amounts of propane-1,3-diamine and molybdenum trioxide in water led to the formation of single crystals of the title salt, (C3H12N2)[MoO4]. The asymmetric unit is comprised of one propane-1,3-diammonium cation and one molybdate anion. The latter is isolated in the structure and has a slightly distorted tetrahedral configuration. An extensive network of N—H...O hydrogen bonds connects anions and cations, giving rise to a compact three-dimensional packing.
Mo-Based Oxidizers as Powerful Tools for the Synthesis of Thia- and Selenaheterocycles.
2019
A highly efficient synthetic protocol for the synthesis of thia- and selenaheterocycles has been developed. By employing a MoCl5 -mediated intramolecular dehydrogenative coupling reaction, a broad variety of structural motifs was isolated in yields up to 94 %. The electrophilic key transformation is tolerated by several labile moieties like halides and tertiary alkyl groups. Due to the use of disulfide or diselenide precursors, a high atom efficiency was achieved.
From Food Map to FODMAP in Irritable Bowel Sindrome.
2016
Irritable bowel syndrome (IBS) is one of the most common gastrointestinal diseases in the general population, with a prevalence ranging from 12 % to 30 %, mainly affecting younger patients (i.e., <50 years of age) and women [1]. As in other chronic functional gastrointestinal disorders, abdominal discomfort or pain, abnormal bowel habits, and often bloating and abdominal distension are the main clinical features. Their diagnosis is based on symptom patterns (i.e., the Rome III criteria), which also allow categorization in diarrhea-predominant (D-IBS), constipation-predominant (C-IBS), mixed diarrhea and constipation (M-IBS), and unclassified (U-IBS) IBS [2]. Symptom severity ranges from tol…