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The reaction of 2-aminothiazole C3H4N2S with tricarbonyl (1-4- η -5- N -pyridiniocyclohexa-1,3-diene) iron tetrafluoroborate complex [C11H12NFe(CO)3]+[BF4]− 1 , a precursor of the highly reactive cation [Fe(CO)3(1-5- η -C6H7)]+, afforded a new tricarbonyl (1-4- η -5- N -2-aminothiazoliocyclohexa-1,3-diene) iron complex of formula C9H10N2S Fe(CO)3 2. The structure of this complex was characterized by IR, 1H NMR spectroscopy and single crystal X-ray diffraction analysis which showed that the labelled complex 2 adopts an exo-enantiomer. In the crystal packing, the components of the structure are linked via intermolecular N–H⋯N hydrogen bonds to form dimeric chains running along the b axis direction. The antimicrobial activity of the free ligands 2-aminothiazole showed significant antibacterial activity. After labeling them, this activity has increased for the complex 2. [ABSTRACT FROM AUTHOR]

Magnetic resonance spectroscopy (MRS) is an imaging diagnostic method that allows non-invasive measurement of metabolites in tissues. The number of metabolites can be identified by standard proton MRS but only a few of them have a clinical significance in diagnosis. The greatest advantages of MRS techniques are their ability to detect multiple tissue-specific metabolites in a single experiment, their quantitative nature and translational component (in vitro/ex vivodiscovered metabolic biomarkers can be translated into non-invasive spectroscopic imaging protocols). In this review, we describe the potential of MRS for brain tumors, prostate and breast cancers in terms of diagnosis, tumor extension assessment, and treatment monitoring. [ABSTRACT FROM AUTHOR]

The reaction of zinc formate with 2-isopropylimidazole at room temperature using toluene as solvent has produced the new complex bisformatobis(2-isopropylimidazole)zinc(II) or [Zn(N2H10C6)2(OOCH)2]. This compound has been characterized using different analytical techniques (elemental analysis, IR and NMR spectroscopies). The spectroscopic analysis (IR, ¹H-NMR, 13C-NMR) showed that this material would have a structure exhibiting the active site observed in certain metalloproteins such as carboxypeptidase A or B. The thermal analysis (TGA) showed that this material is stable up to 100°. [ABSTRACT FROM AUTHOR]

Abstract: Four pentamethylated norbardiene (NBD) models containing imide, bis-imide and diamides were synthesized in the first step of this work with a good yield and characterized by IR, 1HNMR and 13CNMR spectroscopies. These models were used for study, by UV-Visible spectrophotometry, of the photochemical isomerisation under solar radiations of NBD residues, which they contain to quadricyclane (QC). Acquired results show, for all these models, that more than 70 % of NBD are transformed into QC after only 30minutes of solar radiations and following a first order rate. [Copyright &y& Elsevier]

Abstract: Several studies demonstrated the ability of britholites to retain radionuclides such as the caesium and actinides. Therefore, three compounds with formulas Sr8LaCs(PO4)6F2, Sr7La2Cs(PO4)5(SiO4)F2 and Sr2La7Cs(SiO4)6F2, were prepared by solid state reaction. However, it seems that only the mono-silicated composition was obtained in a pure state. In this present work, the X-ray diffraction and magnetic nuclear resonance have been used to investigate the structure for this composition. The results showed that in fact this phase was not pure, but it was mixed with a secondary phase, SrLaCs(PO4)2. The refinement by the Rietveld method allowed also to precise the distribution of La3+ and Cs+ ions between the two cationic sites of the apatite. [Copyright &y& Elsevier]

Abstract: The orange-colored and hydrolytically stable compound {[Ti2O(bhmpc)(Hbhmpc)(H2bhmpc)].C4H8O2.HX}2 (with H3bhmpc = 2,6-bis(hydroxymethyl)-p-cresol and X = OEt or CCl3) has been studied by a combination of single crystal X-ray diffraction data, U.V.-vis. spectroscopy, IR and Raman spectroscopies, 1H, 13C and 17O solution NMR spectroscopies, electron density and statistical thermodynamics modeling. We observed that the molecular structure found in the solid state is conserved in solution. Based on X-ray diffraction data, we also propose a complete and non-ambiguous assignment for the fully resolved 1H and 13C solution NMR spectra through the use of 2D-techniques (COSY, ROESY, HSQC, HMBC) and 1H relaxation time measurements. The ability of the partial charge model introduced more than 20 years ago by J. Livage''s group to reproduce observed 13C NMR chemical shifts in solution is demonstrated. Statistical thermodynamic modeling between Ti(OR)4 (monomers, trimers or tetramers) has shown that complexation was in all cases under entropy control. Possible applications of this soluble and stable precursor to the sol–gel processing of hybrid organic–inorganic are addressed. [Copyright &y& Elsevier]

Abstract: Static and MAS solid-state study of supported phospholipid bilayer cylindrically oriented. Solid-state NMR spectroscopy has been used to investigate a biomimetic model membrane. In this model, the supported bilayers, obtained by fusion of SUVs, are tethered inside nanoporous aluminum oxide supports via a streptavidin/biotin spacer arm. The static and slow Magic-Angle Spinning deuterium NMR spectra of the tethered bilayers have been compared to the experimental and simulated spectra of a simpler model with cylindrical geometry, namely a phospholipid bilayer adsorbed on an oriented polymer (PET) sheet. MAS experimental spectra of both models are in good agreement with the simulated spectrum of an ideal cylindrical distribution of phospholipids. By studying bilayers of DMPC d54, the 2H MAS experiments permit to assess the geometrical arrangement of the lipids inside the nanopores. To cite this article: O. Wattraint, C. Sarazin, C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: Nuclear magnetic spectroscopy (MRS) is a useful method for noninvasively studying intracerebral metabolism. Proton MRS can identify markers of the neuronal viability (N-acetyl-aspartate, NAA), of the metabolism of cellular membranes (choline), of the cellular energy metabolism (creatine, lactate). In Phosphorus MRS, the peaks most readily identified are involved in the high-energy cellular metabolism (ATP, phosphocreatine, inorganic phosphate), and intracellular pH (pHi) can be determined using this method. MRS has been used in experimental models of traumatic brain injury (TBI), primarily to study the cellular metabolism and the relation between biochemical and histological changes after trauma. In trauma patients, significant changes in NAA, choline and pHi were found in both grey and white matter comparing with controls, and these alterations correlated with injury severity. Correlations have been reported between these biochimical changes (reduction in NAA, increase in choline) measured at 1 to 6 months after TBI and the clinical outcome of the patients. However, there are methodological issues which still impede to recommend MRS as a tool for predicting neurological outcome in the clinical setting. [Copyright &y& Elsevier]

A variety of 5-aryl-3-[(1-dialcoxyphosphonyl)methyl]-1,2,4-triazoles 3 has been synthesized efficiently by treatment of trialkylphosphites with 5-aryl-3-chlorométhyl-1,2,4-triazoles 2 . Compound 2 has been prepared by action of N-chloroacylimidates 1 with hydrazines. The structure of triazoles 2 and 3 have been unequivocally confirmed by means of IR, 1 H, 13 C, 31 P NMR spectroscopy and mass spectra. [ABSTRACT FROM AUTHOR]