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121.
Renate Drozdzak Nele Ledoux Bart Allaert Ileana Dragutan Valerian Dragutan Francis Verpoort 《Central European Journal of Chemistry》2005,3(3):404-416
A two step procedure for the synthesis of a novel family of homogeneous and immobilized Ru-complexes containing Schiff bases
as O,N-bidentate ligands is described. The new Ru-complexes have been structurally characterized by IR, Raman,1H-,13C-NMR spectroscopy. The Schiff bases were associated with a diversity of inorganic and organic ligands such as chloride, phosphane,
arenes, various carbenes (alkylidene, vinylidene, indenylidene and allenylidene as well as N-heterocyclic carbenes) and cyclodienes.
By choosing a selective range of substituents for the Schiff base, useful physical and chemical properties of the prepared
Rucomplexes can be induced. This synthetic approach is promising in creating a valuable and diverse selection of Ru-complexes,
valuable for future applications. 相似文献
122.
Steven J. Pachuta Ileana Isern-Flecha R. Graham Cooks 《Journal of mass spectrometry : JMS》1986,21(1):1-5
The site of protonation, methylation and ethylation of anilines, phenols and thiophenols can be determined by tandem mass spectrometry (MS/MS). The extent to which the cation attachment products formed from these compounds undergo charge stripping is related to the site of cation attachment. The formation of doubly charged ions for phenols and anilines is favored when cation attachment occurs on the ring. For thiophenols alkylation occurs almost exclusively on the substituent, and yet an abundant stripping peak is recorded. This behavior is opposite to that seen for anilines and phenols and is accounted for in terms of orbital energies in the three systems. The site of cation attachment, as deduced by charge stripping, agrees with conclusions drawn from the fragmentation behavior of these ions upon collision-induced dissociation. 相似文献
123.
The selective catalytic reduction (SCR) of NO by propane in excess oxygen-containing gas mixture was studied on Co/Al2O3 catalyst. The oxygen concentration is very important for the reaction. The NO conversion to N2 without oxygen is 3% at 800 K and when the O2 concentration is raised up to 8% the NO conversion reaches its maximum value of 60% at 800 K. Characterization results by
TPR and UV-Vis spectroscopy show that in the catalyst, species strongly interacting with tetrahedral and octahedral Co2+ ions in the support are present.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
124.
Here we present some distribution function inequalities between certain functionals defined relative to a convolution approximation procedure. Such inequalities are best known when the approximation is made using dilations of the Gaussian or Cauchy kernels. In these cases, classical differential equations, the heat equation or Laplace's equation, provide the basis for comparisons; in the latter case, the quadratic functional is known as the Lusin area integral. The kernels we consider are compactly supported, and satisfy a dilation equation, rather than a differential equation. For these kernels, there is an intrinsic quadratic variation, defined from the dilation structure. We obtain good lambda distribution function inequalities between a maximal function and the quadratic variation functional. 相似文献
125.
The conformation in solution of new modified nucleosides bearing branched-chain sugars used as building blocks for antisense oligonucleotides is investigated by NMR spectroscopy. Within a classical approach to the conformational study of these molecules, a new methodology is adopted, which is capable of exploring all the possibilities, for a given conformational model, that are compatible with the experimental data. The relationship between conformation of the monomers and hybridization properties of the corresponding oligonucleotides is examined. 相似文献
126.
Gruia MI Oprea E Gruia I Negoita V Farcasanu IC 《Molecules (Basel, Switzerland)》2008,13(5):1195-1206
Lonicera caerulea is a species of bush native to the Kamchatka Peninsula (Russian Far East) whose berries have been extensively studied due to their potential high antioxidant activity. The aim of our work was to investigate the in vivo effects of the antioxidant action of Lonicera caerulea berry extracts on the dynamics of experimentally-induced tumors. Our data showed that aqueous Lonicera caerulaea extracts reduced the tumor volume when administered continuously during the tumor growth and development stages, but augmented the tumor growth when the administration of extracts started three weeks before tumor grafting. Prolonged administration of Lonicera caerulaea berry extracts induced the antioxidant defense mechanism in the tumor tissues, while surprisingly amplifying the peripheral oxidative stress. 相似文献
127.
Pătraşcu Elena Badea Mihaela Čelan Korošin Nataša Cerc Korošec Romana Ruţă Lavinia L. Farcaşanu Ileana C. Grecu Maria Nicoleta Guillaumet Gérald Olar Rodica 《Journal of Thermal Analysis and Calorimetry》2021,143(1):173-184
Journal of Thermal Analysis and Calorimetry - A novel series of Cu(II) complexes with formula M(HLn)(ClO4)2·mH2O [HLn: 13-membered pentaazamacrocyclic ligand resulted from condensation of... 相似文献
128.
Di Poto C Iadarola P Salvini R Passadore I Cereda C Ceroni M Bardoni AM 《Electrophoresis》2007,28(23):4340-4347
Neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson disease (PD) have been associated with increased production of reactive oxygen species. In AD and PD patients, superoxide dismutase (SOD1) was also indicated as a major target of oxidative damage. In particular, in brain tissue of these patients, different SOD1 isoforms have been identified, although their functional role still remains to be elucidated. In the light of the possibility that different SOD1 entities could be expressed also in other neurodegenerative disorders, as a sort of unifying event with AD and PD, we have investigated amyotrophic lateral sclerosis (ALS) using human neuroblastoma SH-SY5Y cells with mutated SOD1 gene H46R as cellular model. 2-DE using a narrow-range IPG 4-7 strips in the first dimension and linear 15% SDS-PAGE in the second allowed to separate different SOD1 spots. MALDI-TOF MS and CapLC-MS/MS have been used for their complete identification. This is the first report in which the presence of SOD1 (iso) forms in a cellular model of ALS has been evidenced. 相似文献
129.
Gerardo Caballero Mariana Gallo JavierM. Montserrat AdolfoM. Iribarren 《Helvetica chimica acta》2002,85(5):1284-1294
We describe the stereoselective synthesis of (2′S)‐2′‐deoxy‐2′‐C‐methyladenosine ( 12 ) and (2′S)‐2′‐deoxy‐2′‐C‐methylinosine ( 14 ) as well as their corresponding cyanoethyl phosphoramidites 16 and 19 from 6‐O‐(2,6‐dichlorophenyl)inosine as starting material. The methyl group at the 2′‐position was introduced via a Wittig reaction (→ 3 , Scheme 1) followed by a stereoselective oxidation with OsO4 (→ 4 , Scheme 2). The primary‐alcohol moiety of 4 was tosylated (→ 5 ) and regioselectively reduced with NaBH4 (→ 6 ). Subsequent reduction of the 2′‐alcohol moiety with Bu3SnH yielded stereoselectively the corresponding (2′S)‐2′‐deoxy‐2′‐C‐methylnucleoside (→ 8a ). 相似文献
130.