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91.
Alexander S. Ivanov Ivan A. Popov Prof. Dr. Alexander I. Boldyrev Prof. Dr. Viktor V. Zhdankin 《Angewandte Chemie (International ed. in English)》2014,53(36):9617-9621
I? X (X=O, N, C) bonding was analyzed in the related hypervalent iodine compounds based on the adaptive natural density partitioning (AdNDP) approach. The results confirm the presence of a I→X σ dative bond, as opposed to the widely used I?X notation. A clear formulation of the electronic structure of these hypervalent iodine compounds would be useful in establishing reaction mechanisms and electronic structures in bioinorganic problems of general applicability. 相似文献
92.
Yuri N. Belokon’Devayani Bhave Daniela D'AddarioElizabetta Groaz Viktor MaleevMichael North Armine Pertrosyan 《Tetrahedron letters》2003,44(10):2045-2048
Copper(salen) complex 1 has been found to catalyse the asymmetric alkylation of enolates derived from a variety of amino acids. There is a clear relationship between the size of the side chain in the substrate and the enantioselectivity of the process, so that the enantioselectivity decreases in the order alanine>aminobutyric acid>allylglycine>leucine>phenylalanine>valine. A transition state model which accounts for the influence of the size of the side chain on the enantioselectivity of the reactions is presented. 相似文献
93.
Nickolay I. Tyryshkin Viktor V. Gavrilov Alexandra V. Fuzhenkova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract It has been known more than for 100 year that triethylphosphine forms the 1:1 adducts with carbon disulfide and isothiocyanates. However, little is know on the reaction of the adducts and the formation of reactive alkylidenephosphoranes was recently reported by the reaction of adducts with electron-poor double bonds. 相似文献
94.
An FT-IR study of pyrrole self-association in CCl4 solutions was carried out. According to the IR measurements, pyrrole forms self-associated dimeric species via N-H?π hydrogen bonding. This was also confirmed by quantum chemical calculations for pyrrole monomer and dimer at B3LYP/6-31++G(d,p) level of theory. A T-shaped minimum was located on B3LYP/6-31++G(d,p) PES of pyrrole dimer characterized with a hydrogen bond of an N-H?π type, with centers-of-mass separation of monomeric units of 4.520 Å, H?π distance of 2.475 Å, the interplanar angle between the two monomeric units being 72.9°. The anharmonic vibrational frequency shift upon dimer formation calculated on the basis of 1D DFT vibrational potentials is in excellent agreement with the experimental data (84 vs. 87 cm−1). Harmonic vibrational analysis predicts somewhat smaller shift (68 cm−1). On the basis of NIR spectroscopic data, anharmonicity constants for the 2ν(N-H) and 2ν(N-H?π) vibrational transitions were calculated. The orientational dynamics of monomeric and self-associated pyrrole species was studied within the framework of the transition dipole moment time correlation function formalism. The period of essentially free rotation in the condensed phase reduces from 0.05 ps for the monomeric pyrrole to 0.02 ps for the proton-donor molecule within the dimer. 相似文献
95.
Sergey V. Bukharov Yulia N. Oludina Roza G. Tagasheva Viktor V. Syakaev Rashid Z. Musin 《Phosphorus, sulfur, and silicon and the related elements》2016,191(7):1069-1074
The synthesis of N-[dimethoxyphosphoryl-(3,5-di-tert-butyl-4-hydroxyphenyl)] methylisatins has been performed by the addition of isatin and 5-butylisatin to the double bond of dimethyl-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)methylphosphonate. Subsequent functionalization of the compounds synthesized with thiosemicarbazide hydrochloride, 3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propionic acid hydrazide, and isonicotinic acid. Hydrazide gave isatin derivatives containing several pharmacophore fragments. Each of them has the ability to the increase the antioxidant and biological activities of these compounds. 相似文献
96.
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98.
Viktor Reshetnikov Steffen Daum Dr. Christina Janko Weronika Karawacka Dr. Rainer Tietze Prof. Dr. Christoph Alexiou Dr. Solomiya Paryzhak Dr. Tetiana Dumych Prof. Dr. Rostyslav Bilyy Dr. Philipp Tripal Dr. Benjamin Schmid Dr. Ralf Palmisano Prof. Dr. Andriy Mokhir 《Angewandte Chemie (International ed. in English)》2018,57(37):11943-11946
Mitochondrial membrane potential is more negative in cancer cells than in normal cells, allowing cancer targeting by delocalized lipophilic cations (DLCs). However, as the difference is rather small, these drugs affect also normal cells. Now a concept of pro‐DLCs is proposed based on an N‐alkylaminoferrocene structure. These prodrugs are activated by the reaction with reactive oxygen species (ROS) forming ferrocenium‐based DLCs. Since ROS are overproduced in cancer, the high‐efficiency cancer‐cell‐specific targeting of mitochondria could be achieved as demonstrated by fluorescence microscopy in combination with two fluorogenic pro‐DLCs in vitro and in vivo. We prepared a conjugate of another pro‐DLC with a clinically approved drug carboplatin and confirmed that its accumulation in mitochondria was higher than that of the free drug. This was reflected in the substantially higher anticancer effect of the conjugate. 相似文献
99.
Viktor Kettmann Jan Lokaj Viktor Milata Jozef Salo Mohamed Mahmoud Mohamed Hasan 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):o365-o366
The title compound, C11H10N3+·Cl?·H2O, belongs to the N1‐methyl‐substituted imidazo[4,5‐f]quinoline family, in which the heterocyclic ring is protonated at the pyridine rather than at the imidazole N atom. The molecule as a whole is almost exactly planar. The molecular structure has been compared with that of the 2‐amino analogue described in the literature, and it was found that the extra amino group of the latter is involved in conjugation with the adjacent double bond, i.e. the conjugation does not extend over the entire heterocyclic system. The cation of the title compound forms a strong hydrogen bond with the Cl? anion and the anions are interconnected by the water solvent molecule. 相似文献
100.
An effective approach is described for the synthesis of binary patterned polymer brushes using a combination of capillary force lithography and surface-initiated polymerization. First, the approach calls for an ultrathin polystyrene (PS) mask to be deposited, in a pattern, over a surface to which a layer of polymerization initiator has already been anchored. Next, surface-initiated atom transfer radical polymerization (ATRP) is performed. This can graft the initial polymer brush onto those areas of the surface unprotected by the PS mask. After grafting is complete, the PS mask is removed and a second brush is synthesized on the newly exposed areas. 相似文献