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51.
We have developed a tandem hetero-Diels–Alder-hemiacetal reaction using arylidene pyruvic acids with 5-(ortho-hydroxybenzylidene)-substituted 4-thioxo-2-thiazolidinones, leading to 6-hydroxy-2-oxo-5-phenyl-3,5a,6,11b-tetrahydro-2H,5H-chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazole-6-carboxylic acids. The stereochemistry of cycloaddition was confirmed by NMR spectra and a single-crystal x-ray diffraction analysis. 相似文献
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Yulia Shepeta Andrii Lozynskyi Marta Sulyma Ihor Nektegayev Philippe Grellier 《Phosphorus, sulfur, and silicon and the related elements》2020,195(10):836-841
AbstractA novel series of [2-(2,6-dichlorophenylamino)-phenyl]-acetic acid N`-3-(substituted)-4-thiazolidin-5-ylidenemethyl-hydrazide derivatives has been designed and synthesized. The structures of synthesized compounds were confirmed by their 1H NMR, 13C NMR and LCMS spectroscopic data. Target compounds were screened for their in vitro anticancer activity according to US NCI protocols, in vitro trypanocidal activity toward Trypanosoma brucei brucei (Tbb) and evaluated for anti-inflammatory activity on the carrageenan edema model in rats. Biological screening data led to identification of compounds 3.3 ([2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid N`-(4-oxo-2-thioxo-thiazolidin-5-ylidenemethyl)-hydrazide) and 3.7 ([2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid N`-(4-oxo-2-thioxo-3-(3-trifluoromethylphenyl)thiazolidin-5-ylidenemethyl)-hydrazide) which demonstrated moderate antitumor activity on the non-small-cell lung cancer NCI-H522 and colon cancer HCT-116 cell lines. Several hit compounds (3.2, 3.4) exhibited the promising and significant inhibition growth of the parasites at micromolar concentrations (IC50 values of 4.8 and 7.06?μM, respectively). The synthesized compounds also demonstrated considerable anti-inflammatory effect comparable to the reference non-steroidal anti-inflammatory drugs (NSAIDs) diclofenac sodium or ketorolac tromethamine. 相似文献
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Andrii Khrabustovskyi 《Mathematical Methods in the Applied Sciences》2009,32(16):2123-2137
We study the asymptotic behavior of the eigenvalues and the eigenfunctions of the Laplace–Beltrami operator on a Riemannian manifold Mε depending on a small parameter ε>0 and whose structure becomes complicated as ε→0. Under a few assumptions on scales of Mε we obtain the homogenized eigenvalue problem. In addition we study the behavior of the heat equation on Mε and investigate the large time behavior of the homogenized equation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Yuriy MatvieievIuliia Karpenko Andrii KulinichAleksey Ryabitskii Vasyl PivovarenkoSvitlana Shishkina Oleg ShishkinVitaly Kalchenko 《Tetrahedron letters》2011,52(30):3922-3925
Cup-shaped calix[4]arenes bearing one or two ketocyanine fluorophore fragments at the wide rim of the macrocycle are synthesized by condensation of formyl calix[4]arenes with arylmethylene(hetarylmethylene)cyclopentanones in the presence of the ionic liquid, dimethylammonium dimethylcarbamate (DIMCARB) and characterized using UV-vis and fluorescence spectroscopy. Strong positive solvatofluorochromism for the calixarene ketocyanines is observed. 相似文献
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Olean Fesenko Andrii Yaremkevich Wolfgang Steinmaurer Battulga Munkhbat Calin Hrelescu Francesco Bonaccorso 《Molecular Crystals and Liquid Crystals》2020,701(1):106-117
AbstractInfrared spectroscopy is widely used technique for observing bioorganic materials, but sometimes scientist have to work with small amount of investigated materials and infrared light interacts poorly with nanometric size molecules. Taking into account unique electro-optical properties of graphene and metal we demonstrated possibility to use metal-graphene nanostructures for label-free detection of thymine. It was shown that IR spectra of thymine adsorbed on the composite nanostructures, such as Au “nanostars” with graphene, is more enhanced than whenthese nanoparticles are used without graphene. The enhancement in IR absorption for complex thymine/Au/graphene depends on size of Au nanoparticlesand thymine’s molecular group. 相似文献
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Dr. Daniel Bůžek Dr. Karel Škoch Soňa Ondrušová Dr. Matouš Kloda Dr. Dmytro Bavol Andrii Mahun Dr. Libor Kobera Dr. Kamil Lang Dr. Michael G. S. Londesborough Dr. Jan Demel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(67):e202201885
The unprecedented co-thermolysis of decaborane(14) (nido-B10H14) and toluene results in a novel porous material (that we have named “activated borane”) containing micropores between 1.0 and 1.5 nm in diameter and a specific surface area of 774 m2 g−1 (Ar, 87 K) that is thermally stable up to 1000 °C. Solid state 1H, 11B and 13C MAS NMR, UV-vis and IR spectroscopies suggest an amorphous structure of borane clusters interconnected by toluene moieties in a ratio of about three toluene molecules for every borane cluster. In addition, the structure contains Lewis-acidic tri-coordinated boron sites giving it some unique properties. Activated borane displays high sorption capacity for pollutants such as sulfamethoxazole, tramadol, diclofenac and bisphenol A that exceed the capacity of commercially-available activated carbon. The consistency in properties for each batch made, and the ease of its synthesis, make activated borane a promising porous material worthy of broad attention. 相似文献
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Kateryna Fominova Taras Diachuk Dmitry Granat Taras Savchuk Vladyslav Vilchynskyi Oleksiy Svitlychnyi Vladyslav Meliantsev Igor Kovalchuk Eduard Litskan Vadym
V. Levterov Valentyn R. Badlo Ruslan I. Vaskevych Alla I. Vaskevych Andrii V. Bolbut Volodymyr V. Semeno Rustam Iminov Kostiantyn Shvydenko Anastasiia S. Kuznetsova Yurii V. Dmytriv Daniil Vysochyn Vasyl Ripenko Andrei A. Tolmachev Olexandra Pavlova Halyna Kuznietsova Iryna Pishel Petro Borysko Pavel K. Mykhailiuk 《Chemical science》2021,12(34):11294
A general approach to a new generation of spirocyclic molecules – oxa-spirocycles – was developed. The key synthetic step was iodocyclization. More than 150 oxa-spirocyclic compounds were prepared. Incorporation of an oxygen atom into the spirocyclic unit dramatically improved water solubility (by up to 40 times) and lowered lipophilicity. More potent oxa-spirocyclic analogues of antihypertensive drug terazosin were synthesized and studied in vivo.A general practical approach to a new generation of spirocyclic molecules – oxa-spirocycles – is developed. 相似文献
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Oleksii Y. Voskoboynik Oleksandra S. Kolomoets Inna S. Nosulenko Galina G. Berest Andrii K. Bilyi Oleksandr V. Karpenko Igor F. Belenichev Sergiy I. Kovalenko 《Journal of heterocyclic chemistry》2019,56(5):1605-1612
Previously unknown 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazoline]‐2,2′‐(7′H)‐diones and their N‐substituted analogues were obtained via reaction of 6‐R1‐3‐(2‐aminophenyl)‐1,2,4‐triazin‐5‐ones with isatin and its substituted derivatives. It was shown that alkylation of 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′‐(7′H)‐diones by N‐R3‐chloroacetamides or chloroacetonitrile in the presence of а base proceeds by N‐1 atom of isatin fragment. The spectral properties (1H and 13C NMR spectra) of synthesized compounds were studied, and features of spectral patterns were discussed. The high‐effective anticonvulsant and radical scavenging agents among 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′(7′H)‐diones and their N‐substituted derivatives were detected. It was shown that compounds 2.2 , 2.8 , and 3.1 exceed or compete the activity of the most widely used in modern neurology drug—lamotrigine on the pentylenetetrazole‐induced seizures model. The aforementioned fact may be considered as a reason for further profound study of synthesized compounds using other pathology models. 相似文献
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An initial-boundary value problem for the multidimensional type III thermoelaticity for a nonsimple material with a center of symmetry is considered. In the linear case, the well-posedness with and without a (second-order in space) Kelvin–Voigt and/or frictional damping in the elastic part as well as the lack of exponential stability in the elastically undamped case are proved. Further, a frictional damping for the elastic component is shown to lead to exponential stability. A Cattaneo-type hyperbolic relaxation for the thermal part is introduced and the well-posedness and uniform stability under a nonlinear frictional damping are obtained using a compactness-uniqueness-type argument. Additionally, a connection between exponential stability and exact observability of unitary strongly continuous groups is established. 相似文献