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71.
Dr. Amandine Cadiau Nikita Kolobov Dr. Sivaranjani Srinivasan Dr. Maarten G. Goesten Dr. Henrik Haspel Dr. Anastasiya V. Bavykina Dr. Mohamed R. Tchalala Dr. Partha Maity Dr. Andrey Goryachev Artem S. Poryvaev Prof. Dr. Mohamed Eddaoudi Dr. Matvey V. Fedin Prof. Dr. Omar F. Mohammed Prof. Dr. Jorge Gascon 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13570-13574
The one-step synthesis and characterization of a new and robust titanium-based metal–organic framework, ACM-1 , is reported. In this structure, which is based on infinite Ti−O chains and 4,4′,4′′,4′′′-(pyrene-1,3,6,8-tetrayl) tetrabenzoic acid as a photosensitizer ligand, the combination of highly mobile photogenerated electrons and a strong hole localization at the organic linker results in large charge-separation lifetimes. The suitable energies for band gap and conduction band minimum (CBM) offer great potential for a wide range of photocatalytic reactions, from hydrogen evolution to the selective oxidation of organic substrates. 相似文献
72.
Ivanova Anastasiya Dvurechensky Pavel Vorontsova Evgeniya Pasechnyuk Dmitry Gasnikov Alexander Dvinskikh Darina Tyurin Alexander 《Journal of Optimization Theory and Applications》2022,193(1):462-490
Journal of Optimization Theory and Applications - Many convex optimization problems have structured objective functions written as a sum of functions with different oracle types (e.g., full... 相似文献
73.
Volodymyr O. Doroschuk Anastasiya B. Grogul Yevhen S. Mandzyuk Oksana G. Makukha Nataliya O. Grytsyk 《Chemical Papers》2016,70(10):1316-1321
A new simple cloud point extraction/preconcentration method was developed for the HPLCMS/MS determination of disulfiram in synthetic urine. Some parameters with an effect on the extraction, such as the concentration of Triton X-114, pH influence, incubation time, equilibration temperature and centrifuging parameters, were studied and optimised. The method proposed for the HPLC-MS/MS determination of disulfiram in synthetic urine with preliminary cloud point extraction was validated. The calibration curve was linear in the range of 0.025–15.4 ng mL?1. The limits of detection (3σ) and quantification (10σ) were 0.008 ng mL?1 and 0.025 ng mL?1, respectively. The matrix effect (96 %), recovery of the extraction procedure (95 %) and overall “process efficiency” (91 %) were also estimated. The results show that the sensitivity, metrological characteristics, ecological safety, simplicity and convenience of the suggested procedure exceed its analogues based on extraction using organic solvents. 相似文献
74.
Gorb L Kaczmarek A Gorb A Sadlej AJ Leszczynski J 《The journal of physical chemistry. B》2005,109(28):13770-13776
The most stable tautomers and rotamers of guanine are characterized by post Hartree-Fock ab initio calculations at the MP2 and CCSD(T) levels employing extended basis sets. Four of the lowest-energy structures (7H-oxo-amino- < 9H-oxo-amino- < 9H-syn-hydroxo-amino- < 9H-anti-hydroxo-amino-guanine) are found to lie within ca. 1 kcal/mol. The next form of guanine is established to lie more than 3 kcal/mol higher than the global minimum tautomer. The transition states of the following reversible reactions: 9H-oxo-amino-guanine right harpoon over left harpoon 9H-syn-hydroxo-amino-guanine right harpoon over left harpoon 9H-anti-hydroxo-amino-guanine have been studied. The calculated energy data were used to obtain thermodynamic parameters and to estimate the composition of the equilibrium mixture of conformers at 0 K and room temperature. The rate constants for the tautomerization of 9H-oxo-amino-guanine were determined by using the instanton approach. Their predicted values characterize an extremely slow chemical process, which is expected to reach the equilibrium in ca. 2500 h. Despite being so slow, we have shown that such a rate of the tautomerization describes a process that is much faster than the one characterized by the observed frequency of spontaneous point mutations. Therefore, additional stabilization factors, e.g., hydrations and interactions with enzymes are necessary to secure the known fidelity of DNA synthesis. 相似文献
75.
Anastasiya P. Mosalkova Dr. Sergei V. Voitekhovich Alexander S. Lyakhov Ludmila S. Ivashkevich Pavel N. Gaponik Oleg A. Ivashkevich 《无机化学与普通化学杂志》2012,638(1):103-110
Three novel 5‐R‐tetrazolato complexes (R = Me, Ph, 4‐Py), namely [Zn2(MeCN4)4(DMSO)2] ( 1 ), [Cu2(PhCN4)4(en)2] · 2DMSO ( 2 ), and [Cu(4‐PyCN4)2(DMSO)2] · 4DMSO ( 3 ), were isolated as unexpected products under attempts to prepare heterometallic tetrazolates using a direct synthesis strategy in the Cu0‐ZnO‐en‐RCN4H‐DMSO system (en = ethylenediamine). The prepared compounds were characterized by elemental, single‐crystal X‐ray, and thermal analyses, and IR spectroscopy. Variation of the 5‐substituent of the tetrazole ring causes different composition of complexes 1 – 3 and diverse coordination modes of 5‐R‐tetrazolato ligands. Complex 1 is a 3D coordination polymer due to N1, N4‐bridging of 5‐methyltetrazolato anions. Complex 2 , with en as a coligand, has a dinuclear structure with two copper atoms linked together by two 5‐phenyltetrazolato ligands by tetrazole N2, N3 bridges. Complex 3 represents a 2D coordination polymer, formed due to 5‐(4‐pyridyl)tetrazolato bridges between adjacent copper atoms (with the tetrazole and pyridine rings nitrogen atoms as coordination centers). DMSO molecules, included in all the compounds, are solvate and/or coordinated ones. 相似文献
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77.
Kseniya V. Belyaeva Ludmila V. Andriyankova Lina P. Nikitina Anastasiya G. Mal’kina Andrei V. Afonin Boris A. Trofimov 《Tetrahedron letters》2012,53(52):7040-7043
1-Substituted imidazoles, isocyanates, and cyanophenylacetylene react under mild (rt), non-catalytic solvent-free conditions to give (Z)-(2-cyano-1-phenylethenyl)imidazole-2-carboxamides in up to 72% yields and with ca. 100% stereoselectivity. The reaction starts from the initial formation of zwitterion/carbene intermediates captured by the isocyanate as the electrophile followed by migration of the alkenyl moiety from the N-3 atom to the anionic center at the carboxamide nitrogen. Thus, the reaction provides an easy access to a novel family of functionalized imidazoles. 相似文献
78.
Boris A. Trofimov Anastasiya G. Mal'kina Valentina V. Nosyreva Alexander I. Albanov Grigorii G. Alexandrov Oleg A. Dyachenko 《Tetrahedron》2009,65(12):2472-288
2-Aminobenzoic acid 1 reacts with α,β-acetylenic γ-hydroxy nitriles 4 and 5 to afford 2-[(5-iminio-2,2-dialkyl-2,5-dihydro-3-furanyl)amino]benzenecarboxylates 7 and 8 (yield 73-74%), a new class of unnatural amino acids in a peculiar zwitterionic form, having the positive charge transferred to the remote imino group of the dihydrofuranyl substituent. 3- and 4-Aminobenzoic acids 2 and 3 with α,β-acetylenic γ-hydroxy nitriles 4-6 undergo entirely different transformations to deliver the esters of cyanomethylhydroxyalkyl ketones 9-12, which result from the unusually facile esterification of the hydroxyl function and simultaneous hydration of the triple bond. 4-Aminobenzoic acid 3 is found to be an active organic catalyst for the one-pot conversion of α,β-acetylenic γ-hydroxy nitrile 4 to 5-amino-2,2-dimethyl-3(2H)-furanone 13, in 80% yield. 相似文献
79.
AA Yurkova EA Khakina SI Troyanov A Chernyak L Shmygleva AS Peregudov VM Martynenko YA Dobrovolskiy PA Troshin 《Chemical communications (Cambridge, England)》2012,48(71):8916-8918
We report Arbuzov-type reactions of chlorofullerene C(60)Cl(6) with trialkyl phosphites producing highly functionalized fullerene derivatives C(60)[P(O)(OR)(2)](5)H with high yields. The designed family of [60]fullerene phosphonic acids and their esters showed unusual properties which might find valuable material science applications. 相似文献
80.
Andrey A. Fokin Ekaterina D. Butova Anastasiya V. Barabash Nhan N. Huu Boryslav A. Tkachenko Natalie A. Fokina 《合成通讯》2013,43(13):1772-1777
We describe a convenient four-step preparation of 1- vinyl adamantane, 1- vinyl diamantane, and 4,9-divinyl diamantane from the respective diamondoid acetic acids in 50–80% isolated yields involving esterification, reduction, and hydrobromination/dehydrobromination. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献