T. P. Klimova

Structure of the cobalt complexes with the Schiff base of salicylaldehyde and lysine according to the H NMR spectroscopic data

The Co(II) complex with the Schiff base of salicylaldehyde and lysine is studied by the 1H NMR method in dioxane and dimethyl sulfoxide (DMSO) solutions. In a dioxane solution, the complex is paramagnetic and dimeric. In the dimer, the cobalt ion coordinates two ligand molecules and each ligand is bound to two cobalt ions. In a water-containing DMSO solution, the complex is diamagnetic due to the oxidation of Co2+ to Co3+.

Structural study of bismuth complexes with diethylenetriaminepentaacetic acid in aqueous solutions

Bismuth complexes with diethylenetriaminepentaacetic acid were examined in aqueous solutions (pH 4–10) by UV, IR, and NMR spectroscopy. In aqueous solutions, the polydentate ligand is coordinated to bismuth through three N atoms and five O atoms.

Pore structure of samples of amorphous silica of various origins by data on 1H NMR

Pore structure of amorphous silica obtained from biogenic and mineral raw materials was studied by the nuclear magnetic resonance (1H NMR) at 200–298 K. As biogenic raw materials were used fruit shells, rice and oats straw, larch needles, horsetail pedicels, and diatomic algae. The pore size distribution in silica samples of various origins was determined.

State of water in amorphous silica samples from rice hulls: A 1H NMR study

Behavior of molecules of adsorbed water in rice hulls, weevil, and amorphous samples of carbon-containing (carbonized, SiO2 content 47%) and pure silica was studied by 1H NMR spectroscopy in the temperature range from 200 to 298 K. The temperature dependence of the signal intensity from humid samples shows a decrease in temperature of freezing of the adsorbed water and presence of unfrozen water. This dependence was used for estimating the pore size distribution. For pure amorphous silica, the pore diameter is in the range from 50 to 150 Å with a maximum at about 85 Å.

An NMR study of the structures of lanthanide diethylenetriaminepentaacetates

The paramagnetic chemical shifts in the 1H and 13C NMR spectra of lanthanide complexes (Ln = Eu, Yb, and Pr) with diethylenetriaminepentaacetic acid were analyzed. It was demonstrated that Eu+3 in aqueous solution can coordinate to one of the carboxylate groups in a chelating bidendate fashion through two O atoms.

Conformational and Functional Disturbances of Serum Albumin Are Characteristic for First Episode Drug-naive Schizophrenic Patients.

Objective Conformational changes of human serum albumin (HSA) can disturb its main functions. Aim To reveal serum albumin disturbances using the high-tech approaches in first episode schizophrenia. Methods First-episode drug-naive schizophrenic (FES) patients were investigated. There were employed laser time resolved subnanosecond fluorescence spectroscopy (LTRSFS) using specific albumin fluorescent probe and high resolution nuclear magnetic resonance (NMR) 1 H spectroscopy. Results There were revealed 3 binding sites in albumin molecule with fluorescent decay time of 1, 3 and 9 nanoseconds (A1, A3 and A9 sites, respectively) in healthy volunteers using LTRSFS approach. There was found significant decrease of fluorescent decay time of probe bound to albumin A3 site of FES patients as compared with controls. It points out on the conformational changes in HSA molecule in FES patients. NMR 1 H spectra of blood serum and its albumin fraction of healthy donors and FES patients were studied. There were shown clear differences in NMR 1 H spectra between these two groups that points out to the conformational changes of albumin molecule in FES patients and disturbances in albumin transport functions. The reaction ability of thiol groups of albumin molecules in FES patients was significantly lower in comparison with healthy persons. It also points out on disturbances of antioxidant albumin properties in FES patients. Conclusion High-tech approaches can be useful for the development of new biomarkers for diagnostic and predicting methods and methods for the evaluation of the efficacy of different types of therapy of mental disorders.

Properties of fluoroantimonates(III) complexes with amino acids

Crystalline complex fluoroantimonates(III) with amino acids (glycine, β-alanine, DL-serine, DL-valine, L-leucine, and L-phenylalanine) have been prepared. The complexes stability in aqueous solutions has been studied with the cementation method. 1H NMR studies of aqueous solutions of the amino acids complexes with SbF3 at pH 1–6 and room temperature are reported. Preparation of polycrystalline metal antimony in aqueous solutions of tetrafluoroantimonates(III) complexes with the protonated amino acids has been demonstrated.

1H NMR and IR Spectroscopic Study of the Structure of the Major Component of the 99mTc HMPAO (Hexamethylpropyleneamino Oxime) Radiopharmaceutical Preparation

Abstractd,l-Hexamethylpropyleneamino oxime (HMPAO) was synthesized and isolated from a mixture of d,l - and meso-isomers. The structure of the conformers was studied using 1H NMR spectroscopy over a broad range of pH. A method for estimating the amount of meso-form present in the mixture of isomers was proposed. It was shown that specific features of the IR spectra depend on the structure of the isomers and on the difference between the packing of molecules in the crystal lattice.