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41.
Camaraza-Medina Yanan Hernandez-Guerrero Abel Luviano-Ortiz Jose Luis 《Journal of Thermal Analysis and Calorimetry》2022,147(21):11805-11821
Journal of Thermal Analysis and Calorimetry - An experimental study is carried out to evaluate the effect of temperature and composition on the variation of seven thermo physical properties... 相似文献
42.
Alisa D. Kharlamova Anton S. Abel Alexei D. Averin Olga A. Maloshitskaya Vitaly A. Roznyatovskiy Evgenii N. Savelyev Boris S. Orlinson Ivan A. Novakov Irina P. Beletskaya 《Molecules (Basel, Switzerland)》2021,26(7)
N-heteroaryl substituted adamantane-containing amines are of substantial interest for their perspective antiviral and psychotherapeutic activities. Chlorine atom at alpha-position of N-heterocycles has been substituted by the amino group using convenient nucleophilic substitution reactions with a series of adamantylalkylamines. The prototropic equilibrium in these compounds was studied using NMR spectroscopy. The introduction of the second amino substituent in 4-amino-6-chloropyrimidine, 2-amino-chloropyrazine, and 1-amino-3-chloroisoquinoline was achieved using Pd(0) catalysis. 相似文献
43.
Claudio Parra Patricio Muoz Luis Bustos Felipe Parra Mario J. Simirgiotis Hugo Escobar 《Molecules (Basel, Switzerland)》2021,26(7)
The Lamiaceae family is an important source of species among medicinal plants highly valued for their biological properties and numerous uses in folk medicine. Origanum is one of the main genera that belong to this family. The purpose of the study was to determine the phenolic composition of the Origanum vulgare extract and evaluate the antimicrobial, antioxidant, and inhibitory activities of this species that grows in the Andean region of the Atacama Desert. High-performance liquid chromatography was performed to determine the main phenols. Rosmarinic acid was identified as the predominant phenolic compound in this species (76.01 mg/100 g DW), followed by protocatechuic acid, which to our knowledge, no previous study reported similar concentrations in O. vulgare. The oregano extract exhibited a content of total phenolic (3948 mg GAE/100 g DW) and total flavonoid (593 mg QE/100 g DW) with a higher DPPH antioxidant activity (IC50 = 40.58 µg/mL), compared to the same species grown under other conditions. Furthermore, it was found to inhibit α-glucosidase activity with an IC50 value (7.11 mg/mL) lower than acarbose (129.32 mg/mL). Pseudomonas syringae and Pantoea agglomerans (both MIC 0.313 mg/mL and MBC 1.25 mg/mL) were the bacteria most susceptible to oregano extract with the lowest concentration necessary to inhibit bacterial growth. These results open the door for the potential use of this plant to manage chronic diseases, and they expand the knowledge of the species cultivated in arid environmental conditions. 相似文献
44.
Jakub Jakowiecki Renata Abel Urszula Orze Pawe Pasznik Robert Preissner Sawomir Filipek 《Molecules (Basel, Switzerland)》2021,26(9)
The CB1 cannabinoid receptor (CB1R) contains one of the longest N termini among class A G protein-coupled receptors. Mutagenesis studies suggest that the allosteric binding site of cannabidiol (CBD) involves residues from the N terminal domain. In order to study the allosteric binding of CBD to CB1R we modeled the whole N-terminus of this receptor using the replica exchange molecular dynamics with solute tempering (REST2) approach. Then, the obtained structures of CB1R with the N terminus were used for ligand docking. A natural cannabinoid receptor agonist, Δ9-THC, was docked to the orthosteric site and a negative allosteric modulator, CBD, to the allosteric site positioned between extracellular ends of helices TM1 and TM2. The molecular dynamics simulations were then performed for CB1R with ligands: (i) CBD together with THC, and (ii) THC-only. Analyses of the differences in the residue-residue interaction patterns between those two cases allowed us to elucidate the allosteric network responsible for the modulation of the CB1R by CBD. In addition, we identified the changes in the orthosteric binding mode of Δ9-THC, as well as the changes in its binding energy, caused by the CBD allosteric binding. We have also found that the presence of a complete N-terminal domain is essential for a stable binding of CBD in the allosteric site of CB1R as well as for the allosteric-orthosteric coupling mechanism. 相似文献
45.
Averin A. D. Uglov A. N. Zubrienko G. A. Abel A. S. Buryak A. K. Beletskaya I. P. 《Russian Chemical Bulletin》2021,70(11):2164-2179
Russian Chemical Bulletin - The Pd-catalyzed tetraarylation of diamines and oxadiamines with 2,7-dibromonaphthalenes and 4,4′-dibromobiphenyl was studied. These reactions gave the... 相似文献
46.
Dr. Olatz Larrañaga Prof. Dr. Ana Arrieta Prof. Dr. Célia Fonseca Guerra Prof. Dr. F. Matthias Bickelhaupt Dr. Abel de Cózar 《化学:亚洲杂志》2021,16(4):315-321
We have quantum chemically studied the structure and nature of alkali- and coinage-metal bonds (M-bonds) versus that of hydrogen bonds between A−M and B− in archetypal [A−M⋅⋅⋅B]− model systems (A, B=F, Cl and M=H, Li, Na, Cu, Ag, Au), using relativistic density functional theory at ZORA-BP86-D3/TZ2P. We find that coinage-metal bonds are stronger than alkali-metal bonds which are stronger than the corresponding hydrogen bonds. Our main purpose is to understand how and why the structure, stability and nature of such bonds are affected if the monovalent central atom H of hydrogen bonds is replaced by an isoelectronic alkali- or coinage-metal atom. To this end, we have analyzed the bonds between A−M and B− using the activation strain model, quantitative Kohn-Sham molecular orbital (MO) theory, energy decomposition analysis (EDA), and Voronoi deformation density (VDD) analysis of the charge distribution. 相似文献
47.
We analyze an advanced two-spring model with an ultralow effective tip mass to predict nontrivial and physically rich "fine structure" in the atomic stick-slip motion in friction force microscopy (FFM) experiments. We demonstrate that this fine structure is present in recent, puzzling experiments. This shows that the tip apex can be completely or partially delocalized, thus shedding new light on what is measured in FFM and, possibly, what can happen with the asperities that establish the contact between macroscopic sliding bodies. 相似文献
48.
M. Teresa de Bustos Muñoz Juan L. G. Guirao Jesús Vigo-Aguiar 《Journal of mathematical chemistry》2014,52(4):1059-1065
The aim of this paper is to study the decomposition of pseudo–radioactive products that follow a dynamics determined by a trigonometric factor. In particular for maps of the form $e^{\cos (\pi t)}$ is proved that an asymptotic sampling recomposition property, generalizing the classical Shannon–Whittaker–Kotel’nikov Theorem, works. 相似文献
49.
Alfredo?Macías Abel?Camacho Luis?F.?Barragán-Gil Claus?L?mmerzahl 《General Relativity and Gravitation》2010,42(3):489-508
The canonical quantization for N = 1 supergravity in the context of gravitational minisuperspace described by Gowdy T
3 and Bianchi class A cosmological models is analyzed in order to search for physical states. There are indeed physical states
in the minisuperspace sector of the theory. This fact entails that the non-physical states conjecture has a restricted validity,
and in consequence it cannot be considered a general result. 相似文献
50.
Namiq G. Shikhaliyev Abel M. Maharramov Khanim N. Bagirova Gulnar T. Suleymanova Biligma D. Tsyrenova Valentine G. Nenajdenko Alexander S. Novikov Victor N. Khrustalev Alexander G. Tskhovrebov 《Mendeleev Communications》2021,31(2):191-193
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