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1.
Komarov Pavel D. Nifant’ev Ilya E. Roitershtein Dmitrii M. Minyaev Mikhail E. 《Journal of chemical crystallography》2021,51(3):352-362
Journal of Chemical Crystallography - The crystal structure of decakis(μ-chloro)-tetrakis(1,2,4-triphenylcyclopentadienyl)-hexakis(tetrahydrofuran)-di-potassium-tetra-neodymium(III)... 相似文献
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Ilya Kolesnikov Daria Mamonova Dmitrii Pankin Gulia Bikbaeva Anastasia Khokhlova Anna Pilip Anastasia Egorova Vladislav Zigel Alina Manshina 《Photochemistry and photobiology》2023,99(3):929-935
Modern progress in photopharmocology calls for new generation of compounds joining bioactivity, photoswitchable properties and high selectivity of response to light wavelength. Introduced here, phosphonate–fullerene hybrids are the first representatives of such compounds. Phosphonate–fullerene hybrids were synthesized on a base of fullerene C60 and organophosphates with the function of photoswitchable cholinesterase activity—phosphorylated thiazolotriazole and aminomalonate compounds and studied with FTIR, UV–VIS spectroscopy and IPC-micro neurotoxin amperometric analysis. As a result of spectroscopic and bioactivity characterization, it was not only demonstrated butyrylcholinesterase (BuChE) inhibition increase in phosphonate–fullerene hybrids compared with pure phosphonates but also pronounced response of inhibition degree to laser irradiation of hybrids. It was found opposite behavior of hybrids as a result of laser irradiation—BuChE inhibition drop-off for thiazolotriazole–fullerene and pronounced growth for aminomalonate–fullerene. The other remarkable peculiarity of presented phosphonate–fullerene hybrids is high selectivity of inhibition change degree to laser wavelength (266 or 325 nm). 相似文献
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Ilya A. P. Jourjine Prof. Dr. Franz Bracher 《European journal of organic chemistry》2023,26(28):e202300399
4-Azafluorenones are typically obtained by acid-mediated cyclization of 2-arylnicotinates. However, this approach fails to give 5-oxygenated 4-azafluorenones due to lactonization of 2-(2-alkoxy)phenylnicotinate intermediates. Herein, we report two modifications of established approaches to 4-azafluorenone synthesis that, either in combination or by themselves, enable the flexible preparation of 4-azafluorenones with diverse oxygenation patterns in the benzenoid ring. Undesired lactonization was circumvented via tert-butyl hydroperoxide (TBHP)-mediated radical cyclization of 2-aryl-3-(hydroxymethyl)pyridines. In the absence of suitable protecting groups for phenolic intermediates, bromide substituents were regioselectively introduced as latent hydroxy groups and later converted under palladium catalysis. We present the first total syntheses of five 4-azafluorenone alkaloids muniranine, darienine, 5,8-dimethoxy-7-hydroxyonychine, 5,6,7,8-tetramethoxyonychine, and 6,8-dihydroxy-7-methoxyonychine in addition to new total syntheses of six 4-azafluorenone alkaloids and one related pyridocoumarin alkaloid. 相似文献
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Mikhail E. Minyaev Dmitrii M. Roitershtein Ilya E. Nifant'ev Ivan V. Ananyev Tatyana V. Minyaeva Timofey A. Mikhaylyev 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(6):491-498
(1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐1,3,5‐triphenylcyclohexan‐1‐ol or (4‐hydroxy‐2,4,6‐triphenylcyclohexane‐1,3‐diyl)bis(phenylmethanone), C38H32O3, (1), is formed as a by‐product in the NaOH‐catalyzed synthesis of 1,3,5‐triphenylpentane‐1,5‐dione from acetophenone and benzaldehyde. Single crystals of the chloroform hemisolvate, C38H32O3·0.5CHCl3, were grown from chloroform. The structure has triclinic (P) symmetry. One diastereomer [as a pair of (1RS,2SR,3RS,4SR,5RS)‐enantiomers] of (1) has been found in the crystal structure and confirmed by NMR studies. The dichoromethane hemisolvate has been reported previously [Zhang et al. (2007). Acta Cryst. E 63 , o4652]. (1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐3,5‐bis(2‐methoxyphenyl)‐1‐phenylcyclohexan‐1‐ol or [4‐hydroxy‐2,6‐bis(2‐methoxyphenyl)‐4‐phenylcyclohexane‐1,3‐diyl]bis(phenylmethanone), C40H36O5, (2), is also formed as a by‐product, under the same conditions, from acetophenone and 2‐methoxybenzaldehyde. Crystals of (2) have been grown from chloroform. The structure has orthorhombic (Pca21) symmetry. A diastereomer of (2) possesses the same configuration as (1). In both structures, the cyclohexane ring adopts a chair conformation with all bulky groups (benzoyl, phenyl and 2‐methoxyphenyl) in equatorial positions. The molecules of (1) and (2) both display one intramolecular O—H...O hydrogen bond. 相似文献
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Artur Vashurin Vladimir Maizlish Ilya Kuzmin Oleg Petrov Mikhail Razumov Svetlana Pukhovskaya Oleg Golubchikov Oscar Koifman 《Journal of inclusion phenomena and macrocyclic chemistry》2017,87(1-2):37-43
The influence of the size of conjugated π-system on catalytic activity of cobalt complex with β-octaphenylporphyrin and its tetraaza-, tetrabenzo and tetrabenzotetraaza derivatives was studied in present work. It is found that catalytic activity for oxidation of sulfur-containing compounds increases under extension of conjugated macrocycle system according to the following series CoP < CoBP ≤ CoPz < CoPPz ? CoPc. 相似文献