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951.
Fuks Olga Ibrahima Fayadhoi Tomin Pavel A. Tchelepi Hamdi 《Transport in Porous Media》2020,132(1):113-133
Transport in Porous Media - The paper presents a novel approach for uncertainty propagation in multicomponent two-phase displacements. This approach originates from and extends the frozen... 相似文献
952.
Dmitriy V. Maltsev Alexander A. Spasov Pavel M. Vassiliev Maria O. Skripka Mikhail V. Miroshnikov Andrey N. Kochetkov Nataliya V. Eliseeva Yuliya V. Lifanova Tatyana A. Kuzmenko Lyudmila N. Divaeva Anatolii S. Morkovnik 《Molecules (Basel, Switzerland)》2021,26(19)
A number of novel 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole derivatives 2 were obtained by alkylation mainly in the 1H-tautomeric form of 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole or its 8,9-dimethyl-substituted analog 4-chlorobenzyl bromide, 4-chloroacetic acid fluoroanilide, and 4-tert-butylphenacyl bromide in neutral medium. Compounds 3 were cyclized and synthesized earlier with 11-phenacyl-substituted diazepino[1,2-a]benzimidazoles upon heating in conc. HBr. The chemical structures of the compounds were clarified by using the 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR) technique. Anxiolytic properties were evaluated using the elevated plus maze (EPM) and open field (OF) tests. The analgesic effect of compounds was estimated with the tail flick (TF) and hot plate (HP) methods. Besides, possible the influence of the test compounds on motor activities of the animals was examined by the Grid, Wire, and Rotarod tests. Compounds 2d and 3b were the most active due to their prominent analgesic and anxiolytic potentials, respectively. The results of the performed in silico analysis showed that the high anxiolytic activity of compound 3b is explained by the combination of a pronounced interaction mainly with the benzodiazepine site of the GABAA receptor with a prominent interaction with both the specific and allosteric sites of the 5-HT2A receptor. 相似文献
953.
Alexander S. Lyakhov Sergey V. Voitekhovich Pavel N. Gaponik Ludmila S. Ivashkevich 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o388-o389
The title compound, C8H13N5, is a novel functionally substituted 5‐alkyltetrazole. The substituent on the tetrazole C atom is symmetrical, with intrinsic symmetry close to m. There is intermolecular N—H⃛N hydrogen bonding between adjacent tetrazole rings, which is responsible for the formation of one‐dimensional polymeric chains running along the c axis. The polycrystalline compound exhibits frequency doubling for incident light (λ = 1064 nm) from a YAG:Nd pulsed laser. 相似文献
954.
Jaromír Marek Pavel Kopel Zdenk Trvní
ek 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):m558-m560
In the crystal structure of the title compound, [N,N′‐bis(3‐aminopropyl)ethylenediamine‐κ4N,N′,N′′,N′′′][1,3,5‐triazine‐2,4,6(1H,3H,5H)‐trithionato(2−)‐κ2N,S]zinc(II) ethanol solvate, [Zn(C8H22N4)2(C3HN3S3)]·C2H6O, the ZnII atom is octahedrally coordinated by four N atoms [Zn—N = 2.104 (2)–2.203 (2) Å] of a tetradentate N‐donor N,N′‐bis(3‐aminopropyl)ethylenediamine (bapen) ligand and by two S and N atoms [Zn—S = 2.5700 (7) Å and Zn—N = 2.313 (2) Å] of a trithiocyanurate(2−) (ttcH2−) dianion bonded as a bidentate ligand in a cis configuration. The crystal structure of the compound is stabilized by a network of hydrogen bonds. 相似文献
955.
Alexander S. Lyakhov Andrey N. Vorobiov Pavel N. Gaponik Ludmila S. Ivashkevich Vadim E. Matulis Oleg A. Ivashkevich 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o690-o693
In the molecules of 5‐amino‐1‐phenyltetrazole, C7H7N5, (I), and 5‐amino‐1‐(1‐naphthyl)tetrazole, C11H9N5, (II), the tetrazole rings and aryl fragments are not coplanar; corresponding dihedral angles are 50.58 (5) and 45.19 (7)° for the two independent molecules of (I), and 64.14 (5)° for (II). Intermolecular N—H⋯N hydrogen bonds between the amino groups and tetrazole N atoms are primarily responsible for formation of two‐dimensional networks extending parallel to the bc plane in both compounds. The presence of the amino group has a distinct effect on the geometry of the tetrazole rings in each case. 相似文献
956.
Pavel Pospisil BeatriceD. Pilger Stefania Marveggio Pierre Schelling Christine Wurth Leonardo Scapozza Gerd Folkers Mario Pongracic Mladen Mintas SilvanaRaic Malic 《Helvetica chimica acta》2002,85(10):3237-3250
In the context of broadening the knowledge on substrate specificity of Herpes simplex virus type 1 thymidine kinase (HSV‐1 TK) and Varicella‐Zoster virus thymidine kinase (VZV TK), new derivatives of 9‐(2‐hydroxypropyl)‐substituted adenine, chloropurine, hypoxanthine, guanine, thiopurine, and (methylsulfanyl)purine were synthesized and subjected to in vitro phosphorylation and binding affinity assays. The interactions between the compounds and the crystallographically determined active site residues of HSV‐1 TK have been studied by molecular modeling with the Lamarckian genetic algorithm of docking program AutoDock 3.0. All compounds mentioned bind to both enzymes in the low mM to sub‐mM range, comparable to binding affinities of existing prodrugs. Findings from the docking procedure indicate multiple binding modes for all of the compounds and are in accordance with the results of phosphorylation and binding‐affinity studies. Furthermore, the studies reveal that hypoxanthine derivatives represent a new class of TK substrates and thiopurine derivatives a new class of TK inhibitors. 相似文献
957.
958.
Irene L. Odinets Natalya M. Vinogradova Konstantin A. Lyssenko Michail Yu. Antipin Pavel V. Petrovskii Tatyana A. Mastryukova 《Heteroatom Chemistry》2002,13(1):1-21
Intramolecular S‐alkylation in a series of ω‐haloalkyl‐substituted thiophosphorylacetonitriles 5–7 presents an effective synthetic route to the hitherto unknown 3‐cyano‐2‐oxo‐1,2‐thiaphospholanes 14 and thiaphosphinanes 15 . The compounds were obtained as a mixture of cis‐ and trans‐isomers that were resolved to individual stereoisomers in most cases. For some of them, X‐ray diffraction analysis has been performed. It was shown that 31P NMR spectroscopy can be used to assign the stereochemistry of 3‐cyano‐2‐oxo‐1,2‐thiaphosphacyclanes. © 2002 John Wiley & Sons, Inc. Heteroatom Chem 13:1–21, 2002; DOI 10.1002/hc.1101 相似文献
959.
Alexandr I. Alimpiev Valeri S. Gulev Pavel W. Mokruchniko 《Crystal Research and Technology》1995,30(3):295-297
The fields of crystallization in the system La2O3–BeO–Al2O3 are investigated. Single crystals of LaBeAl11O19 were grown by the Czochralski technique. 相似文献
960.
The combination of IR, Raman and NMR spectroscopy was used in the study of the blends of semicrystalline and amorphous polymers with considerably different strength of intermolecular interactions: poly(ϵ-caprolactam)/polystyrene (PCL/PS), poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) and poly(N-methyllaurolactam)/poly(4-vinylphenol) (PNMLL/PVPh). In the vibrational and NMR spectra of the blends composed of non-interacting polymers (PCL/PS) and weakly interacting polymers (PEO/PMMA), no band changes were observed which would indicate changes of the conformational structures. 1H NMR relaxation of the PCL and PS components in the blends is the same as in the respective homopolymers similarly treated. In the blends of weakly interacting polymers (PEO/PMMA), the crystallinity of PEO is influenced by the presence of PMMA and is negligible in the blends with less than 30 wt.-% of PEO. The rotating-frame spin-lattice relaxation time for protons TH1p of PMMA indicates close contact of the PMMA and PEO chains. In the blends PNMLL/PVPh with strong hydrogen-bonding interactions, both components are intimately mixed on a scale of 3–4 nm and significant shifts of some bands both in vibrational and in NMR spectra reveal changes of structure. 相似文献