排序方式: 共有47条查询结果,搜索用时 15 毫秒
1.
I. A. Uspenskaya Z. S. Vakhovskaya M. M. Efremova M. L. Kovba A. L. Emelina Zh. V. Dobrokhotova Yu. V. Goryushkina L. A. Tiflova A. A. Popova A. S. Monaenkova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(4):529-534
The thermodynamic properties of the Ln2BaO4 phases (Ln = Dy, Ho, Sm) were studied by the electromotive force method with a fluoride electrolyte (890–1180 K), solution calorimetry in 1.07 N hydrochloric acid at 298.15 K, and differential scanning calorimetry (298–860 K). The experimental data were jointly processed, and the thermodynamic functions of the compounds over the temperature range 298–1200 K were calculated. 相似文献
2.
Design of pincer complexes based on (methylsulfanyl)acetic/propionic acid amides with ancillary S‐ and N‐donors as potential catalysts and cytotoxic agents 下载免费PDF全文
Svetlana G. Churusova Diana V. Aleksanyan Andrei A. Vasil'ev Ekaterina Yu. Rybalkina Olga Yu. Susova Zinaida S. Klemenkova Rinat R. Aysin Yulia V. Nelyubina Vladimir A. Kozlov 《应用有机金属化学》2018,32(6)
Pincer complexes featuring readily tunable tridentate ligand frameworks comprise one of the most actively studied classes of organometallic and metal–organic compounds and find extensive use in catalysis, organic synthesis, materials science, and other fields of chemistry and allied disciplines. Currently growing attention is devoted to non‐classical ligand scaffolds, such as functionalized carboxamides, which offer multiple options for directed structural modifications. In this study, the reactions of (methylsulfanyl)acetyl and propanoyl chlorides with 2‐(aminomethyl)pyridine, 2‐(2‐aminoethyl)pyridine, 8‐aminoquinoline and 2‐(diphenylthiophosphoryl)aniline afford a series of new pincer‐type ligands based on functionalized carboxamides. The ligands obtained readily undergo direct cyclopalladation under the action of PdCl2(NCPh)2 in dichloromethane at room temperature, resulting in Pd(II) pincer complexes with N,N,S‐ and S,N,S‐donor sets. Importantly, some of the cyclopalladated derivatives can also be produced efficiently under solvent‐free conditions according to the approach recently developed by our group. The complexes obtained have been tested for cytotoxicity against several human cancer cell lines and catalytic activity in the model Suzuki reaction. The results have been compared to those for the related Pd(II) pincer complexes to define the main structure–activity relationships and to outline the most promising structures for further investigations. 相似文献
3.
Physicochemical and adsorption properties of hypercross‐linked polystyrene with ultimate cross‐linking density 下载免费PDF全文
Maria P. Tsyurupa Zinaida K. Blinnikova Yuri A. Borisov Mikhail M. Ilyin Tamara P. Klimova Kiril V. Mitsen Vadim A. Davankov 《Journal of separation science》2014,37(7):803-810
The paper describes unexpected properties of hypercross‐linked polystyrenes with ultimate cross‐linking degrees of 300, 400, and 500%, where three, four, or five methylene links, respectively, could bind each polystyrene phenyl ring to its spacious neighbors. The polymers exhibit a strong electron spin resonance signal, unusual spectra in IR, UV, and visible ranges, and they are not typical dielectrics. The nonfunctionalized hypercross‐linked polymers absorb significant amounts of inorganic acids, salts, and bases due to interactions of protons or other cations with electron‐donating fragments of the aromatic network with the high extent of mutual connectivity and also due to dispersion interactions of anions with the polymer matrix. 相似文献
4.
Diana V. Aleksanyan Yulia V. Nelyubina Zinaida S. Klemenkova Vladimir A. Kozlov 《Phosphorus, sulfur, and silicon and the related elements》2014,189(7-8):1028-1042
AbstractNovel phosphorus-containing ligands have been synthesized by the condensation of 2-(thio)phosphorylated anilines with 2,6-dichloro- and 4-chloropyridine-2-carbonyl chlorides in the presence of Et3N and unsubstituted pyridine-2-carboxylic acid using P(OPh)3 as a coupling agent. The compounds derived readily form complexes with a range of transition metals (M=Re(I), Pd(II), and Cu(II)), serving as bi- or tridentate monoanionic ligands. The composition and structure of the resulting metallocycles depend both on the presence/amount of the Cl atoms in the pyridine ring and on the nature of the donor atom X in the P=X moiety. The novel compounds were characterized by multinuclear NMR and IR spectroscopy as well as X-ray crystallography. 相似文献
5.
Boris A. Trofimov Lyubov'' N. Sobenina Zinaida V. Stepanova Tamara I. Vakul''skaya Ol''ga N. Kazheva Grigorii G. Aleksandrov Oleg A. Dyachenko Al''bina I. Mikhaleva 《Tetrahedron》2008,64(23):5541-5544
The solvent-free interaction of 2-phenylpyrrole with bromobenzoylacetylene (room temperature) upon their grinding with solid metal oxides (MgO, CaO, ZnO, BaO, Al2O3, TiO2, ZrO2) and salts (CaCO3, ZrSiO4) leads to either the cross-coupling product or the adduct of pyrrole addition to the riple bond of acetylene. The ethynylation is accompanied by the formation of intermediate and side products: E-2-(1-bromo-2-benzoylethenyl)-5-phenylpyrrole and 1,1-di(5-phenylpyrrol-2-yl)-2-benzoylethene. The activity of the metal oxides in the ethynylation reaction falls in the order (in the brackets, the content of 2-benzoylethynyl-5-phenylpyrrole in the reaction mixture is given): ZnO (81%), BaO (73%), Al2O3 (71%), MgO (69%), CaO (50%). The oxides, SiO2, TiO2, ZrO2, and the salts, CaCO3 and ZrSiO4, are inactive in the ethynylation reaction affording only the intermediate adduct, with ZrO2 the isolated yield of the bromoethenylpyrrole reaching 60%. ESR monitoring shows the reaction to start from one electron transfer from pyrrole to acetylene mediated by the oxide surface. The adduct is readily converted on Al2O3 to 2-(benzoylethynyl)-5-phenylpyrrole crystallized mostly as cis-rotamer (X-ray data). 相似文献
6.
Novel Mechanism of Bioluminescence: Oxidative Decarboxylation of a Moiety Adjacent to the Light Emitter of Fridericia Luciferin 下载免费PDF全文
Maxim A. Dubinnyi Zinaida M. Kaskova Natalja S. Rodionova Mikhail S. Baranov Andrey Yu. Gorokhovatsky Alexey Kotlobay Kyril M. Solntsev Aleksandra S. Tsarkova Valentin N. Petushkov Ilia V. Yampolsky 《Angewandte Chemie (International ed. in English)》2015,54(24):7065-7067
A novel luciferin from a bioluminescent Siberian earthworm Fridericia heliota was recently described. In this study, the Fridericia oxyluciferin was isolated and its structure elucidated. The results provide insight into a novel bioluminescence mechanism in nature. Oxidative decarboxylation of a lysine fragment of the luciferin supplies energy for light generation, while a fluorescent CompX moiety remains intact and serves as the light emitter. 相似文献
7.
Dielectric measurements on samples consisting of banana-shaped molecules with a polymorphism I/SmCPA/B7 have been performed for the first time. The dielectric increment for the reorientation of the molecules about the long axis, and the corresponding relaxation time, surprisingly decrease at the SmCPA/B7 transition. This effect is discussed in terms of the undulated structure which partially destroys the ferroelectric short range order. Decreasing temperature gives an even stronger hindrance for this reorientation and could explain controversial results obtained in the B7 phases of different samples. At lower temperatures a further mesophase was detected. This was additionally observed by calorimetric and atomic force microscopy methods. 相似文献
8.
Z. Vakhovskaya J. Lorenzo Chao U. Baumeister K. Pelz M.W. Schröder W. Weissflog 《Phase Transitions》2013,86(6):470-484
Three new homologous bent-shaped mesogens with terminal octyloxy P8, decyloxy P10 and dodecyloxy P12 groups were synthesized. Calorimetric, X-ray and electro-optic investigations prove the existence of two mesophases of the SmCPA type for compound P10 but only one SmCPA phase for the homologues P8 and P12. The static dielectric permittivities of compound P12 and that of the low-temperature phase of substance P10 are in the order of 30 and agree with results on bent-core mesogens published before. Surprisingly, the dielectric permittivities of P8 and of the high-temperature phase of P10 are of about 1000. We explain this extremely high dielectric response with the soft reaction of ferroelectric units in the external electrical field. 相似文献
9.
Boris A. Trofimov Lyubov N. Sobenina Zinaida V. Stepanova Olga V. Petrova Igor A. Ushakov Albina I. Mikhaleva 《Tetrahedron letters》2008,49(24):3946-3949
4,5,6,7-Tetrahydroindoles undergo a rapid, facile (rt, 60 min) ethynylation with ethyl 3-halo-2-propynoates upon grinding with solid K2CO3 (without solvent) at C-2 of the tetrahydroindole ring to afford ethyl 3-(4,5,6,7-tetrahydroindol-2-yl)-2-propynoates in 62–90% yield. 相似文献
10.
Fakhrullin RF Vinter VG Zamaleeva AI Matveeva MV Kourbanov RA Temesgen BK Ishmuchametova DG Abramova ZI Konovalova OA Salakhov MK 《Analytical and bioanalytical chemistry》2007,388(2):367-375
We report the development of a novel quartz crystal microbalance immunosensor with the simultaneous measurement of resonance
frequency and motional resistance for the detection of antibodies to double-stranded DNA (dsDNA). The immobilization of poly(l-lysine) and subsequent complexation with DNA resulted in formation of a sensitive dsDNA-containing nanofilm on the surface
of a gold electrode. Atomic force microscopy has been applied for the characterization of a poly(l-lysine)–DNA film. After the blocking with bovine serum albumin, the immunosensor in flow-injection mode was used to detect
the antibodies to dsDNA in purified protein solutions of antibodies to dsDNA and to single-stranded DNA, monoclonal human
immunoglobulin G, DNase I and in blood serum of patients with bronchial asthma and systemic lupus erythematosus. Experimental
results indicate high sensitivity and selectivity of the immunosensor.
In memoriam Prof. Victor G. Vinter 相似文献