Cadmium-113 shielding tensors of cadmium compounds. 7. X-ray structure and cadmium-113 NMR studies of poly(bis(acetato)bis(imidazole)cadmium(II)). A model compound for cadmium-substituted carboxypeptidase-A and thermolysin

Background: Ischemic heart disease, cerebrovascular accident, and venous thromboembolism have the presence of a thrombotic event in common and represent the most common causes of death within the population. Objective: Since Schiff base copper(II) complexes are able to interact with polyphosphates (PolyP), a procoagulant and potentially prothrombotic platelet agent, we investigated the antiplatelet aggregating properties of two novel tridentate Schiff base ligands and their corresponding copper( II) complexes. Methods: The Schiff base ligands (L1) and (L2), as well as their corresponding copper(II) complexes (C1) and (C2), were synthesized and characterized by chemical analysis, X-ray diffraction, mass spectrometry, and UV-Visible, IR and far IR spectroscopy. In addition, EPR studies were carried out for (C1) and (C2), while (L1) and (L2) were further analyzed by 1H and 13C NMR. Tests for antiplatelet aggregation activities of all of the four compounds were conducted. Results: X-ray diffraction studies show that (L1) and (L2) exist in the enol-imine tautomeric form with a strong intramolecular hydrogen bond. NMR studies show that both ligands are found as enol-imine tautomers in CDCl3 solution. In the solid state, the geometry around the copper(II) ion in both (C1) and (C2) is square planar. EPR spectra suggest that the geometry of the complexes is similar to that observed in the solid state by X-ray crystallography. Compound (C2) exhibited the strongest antiplatelet aggregation activity. Conclusion: Schiff base copper(II) complexes, which are attracting increasing interest, could represent a new approach to treat thrombosis by blocking the activity of PolyP with a potential anticoagulant activity and, most importantly, demonstrating no adverse bleeding events.

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Modification of Wood with Monoethanolamino-borate by The Data of X-Ray Photoelectron Spectroscopy

MATEC Web of Conferences ◽

10.1051/matecconf/201819604005 ◽

2018 ◽

Vol 196 ◽

pp. 04005

Author(s):

Irina Stepina ◽

Irina Kotlyarova

Keyword(s):

Particle Size ◽

Photoelectron Spectroscopy ◽

Model Compound ◽

Hydrolytic Stability ◽

Photoelectron Spectra ◽

Wood Cellulose ◽

Rapid Loss ◽

X Ray ◽

Wood Protection ◽

Cellulose Materials

The difficulty of wood protection from biocorrosion and fire is due to the fact that modifiers in use are washed out from the surface of the substrate under the influence of environmental factors. This results in a rapid loss of the protective effect and other practically important wood characteristics caused by the modification. To solve this problem is the aim of our work. Here, monoethanolaminoborate is used as a modifier, where electron-donating nitrogen atom provides a coordination number equal to four to a boron atom, which determines the hydrolytic stability of the compounds formed. Alpha-cellulose ground mechanically to a particle size of 1 mm at most was used as a model compound for the modification. X-ray photoelectron spectra were recorded on the XSAM-800 spectrometer (Kratos, UK). Prolonged extraction of the modified samples preceded the registration of the photoelectron spectra to exclude the fixation of the modifier molecules unreacted with cellulose. As a result of the experiment, boron and nitrogen atoms were found in the modified substrate, which indicated the hydrolytic stability of the bonds formed between the modifier molecules and the substrate. Therefore monoethanolaminoborate can be considered as a non-extractable modifier for wood-cellulose materials.

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Solution multinuclear (31P,111Cd,77Se) magnetic resonance studies of cadmium complexes of heterocyclic aromatic thiones and the structure of [tetrakis(2(1H)-pyridinethione)cadmium] nitrate, [Cd(C5H5NS)4](NO3)2

Canadian Journal of Chemistry ◽

10.1139/v00-070 ◽

2000 ◽

Vol 78 (5) ◽

pp. 590-597 ◽

Cited By ~ 22

Author(s):

Umarani Rajalingam ◽

Philip AW Dean ◽

Hilary A Jenkins

Keyword(s):

Cadmium Nitrate ◽

Cadmium Complexes ◽

Nmr Studies ◽

X Ray ◽

X Ray Crystallography ◽

Stoichiometric Reaction ◽

Complex Salts ◽

Reduced Temperature ◽

Aromatic Heterocyclic ◽

Phosphine Chalcogenides

The complex salts CdL4(O3SCF3)2 (L = 2(1H)-pyridinethione (Py2SH), 4(1H)-pyridinethione (Py4SH), or 2(1H)-quinolinethione (Q2SH)) have been synthesized by the stoichiometric reaction of Cd(O3SCF3)2 and the appropriate thione. Both ambient-temperature 13C and reduced-temperature 111Cd NMR of CdL4(O3SCF3)2 in solution are consistent with L being bound through sulfur. Reduced-temperature NMR (31P, 77Se, 111Cd, as appropriate) of mixtures of CdL4(O3SCF3)2 and Cd(EPCy3)4(O3SCF3)2 (E = Se, Cy = c-C6H11) and of Cd(EPCy3)4(O3SCF3)2 (E = S, Se) and L in solution provides evidence for various [CdLn(EPCy3)4-n]2+. Similarly, reduced-temperature metal NMR of [CdL4]2+ and [CdL'4]2+ (L, L' = Py2SH, Py4SH, Q2SH; L not equal L') in solution shows the formation of [CdLnL'4-n]2+. Thus it has been demonstrated that at reduced temperature [CdL4]2+ is intact in solution and exchange of L is slow on the timescale of the metal chemical shift differences. From the NMR studies of Cd(EPCy3)4(O3SCF3)2 (E = S, Se):L mixtures, the binding preferences are found to be L > EPCy3 in solution. Similarly, from the reduced temperature metal NMR spectra of mixtures where L and L' compete for Cd(II) in solution, the binding preferences are Py4SH > Py2SH > Q2SH. The structure of Cd(Py2SH)4(NO3)2 (4) has been determined by single crystal X-ray analysis. Colorless crystals of 4 are tetragonal, I4(1)/acd with 8 molecules per unit cell of dimensions a = 18.660(3), c = 15.215(3) Å. The structure is comprised of recognizable NO3- anions and [Cd(Py2SH)4]2+ cations. In the cations, which have S4 symmetry, the ligands are S-bound. A network of NH···O hydrogen bonds links the cations and anions.Key words: aromatic heterocyclic thiones, cadmium complexes, phosphine chalcogenides, 111Cd, 31P, 77Se NMR, X-ray crystallography.

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Comprehensive Characterisation of the Ketoprofen-β-Cyclodextrin Inclusion Complex Using X-ray Techniques and NMR Spectroscopy

Molecules ◽

10.3390/molecules26134089 ◽

2021 ◽

Vol 26 (13) ◽

pp. 4089

Author(s):

Katarzyna Betlejewska-Kielak ◽

Elżbieta Bednarek ◽

Armand Budzianowski ◽

Katarzyna Michalska ◽

Jan K. Maurin

Keyword(s):

Nmr Spectroscopy ◽

Inclusion Complex ◽

Crystal And Molecular Structure ◽

Binding Constants ◽

Nmr Studies ◽

X Ray ◽

Cyclodextrin Inclusion ◽

Powder Samples ◽

Cyclodextrin Inclusion Complex ◽

Co Precipitation

Racemic ketoprofen (KP) and β-cyclodextrin (β-CD) powder samples from co-precipitation (1), evaporation (2), and heating-under-reflux (3) were analysed using X-ray techniques and nuclear magnetic resonance (NMR) spectroscopy. On the basis of NMR studies carried out in an aqueous solution, it was found that in the samples obtained by methods 1 and 2, there were large excesses of β-CD in relation to KP, 10 and 75 times, respectively, while the sample obtained by method 3 contained equimolar amounts of β-CD and KP. NMR results indicated that KP/β-CD inclusion complexes were formed and the estimated binding constants were approximately 2400 M−1, showing that KP is quite strongly associated with β-CD. On the other hand, the X-ray single-crystal technique in the solid state revealed that the (S)-KP/β-CD inclusion complex with a stoichiometry of 2:2 was obtained as a result of heating-under-reflux, for which the crystal and molecular structure were examined. Among the methods used for the preparation of the KP/β-CD complex, only method 3 is suitable.

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Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽

10.3390/polym13040558 ◽

2021 ◽

Vol 13 (4) ◽

pp. 558

Author(s):

Wenhui Zhu ◽

Caiyun Zhang ◽

Yali Chen ◽

Qiliang Deng

Keyword(s):

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Degradation Rate ◽

Model Compound ◽

Vibrating Sample Magnetometer ◽

Simulated Sunlight ◽

X Ray Diffraction ◽

X Ray ◽

Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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