518 research outputs found
Copper catalyzed reaction of hydrazones with polyhalogenated compounds. An efficient approach to alkenes and diazadienes
Catalytic olefination reaction represents new approach to the preparation of double C=C bond. N-unsubstituted hydrazones can be converted into alkenes by treatment with polyhalogenated alkanes in presence of a base and catalytic amounts of copper salts. The reaction has a wide synthetic scope allowing to prepare both alkyl and aryl substituted alkenes, including fluorinated and functionalized ones. We demonstrated also similar transformation with N-substituted hydrazones, as a result the new carbon-carbon bond forming reaction of N-monosubstituted hydrazones with polyhaloalkanes to produce 1,2-diazabuta-1,3-dienes has been developed. This highly efficient copper-catalyzed transformation features a broad scope with regard to all reaction components, as well as the possibility to perform the process in a much more convenient one-pot fashion starting with easily available aldehydes and hydrazines. The synthetic usefulness of the obtained halogenated azadienes was demonstrated in their reactions with O-, N-, S- and C-nucleophiles, which opened access to a variety of valuable acyclic and heterocyclic products. Mechanistic studies revealed that this Cu-catalyzed transformation proceeds via radical pathway.This work was supported by a research grant from RFBR grant 18-03-00791
(Z)-2-(2-Chloro-3,3,3-trifluoroprop-1-enyl)-6-methoxyphenyl acetate
The crystal structure of the title compound, C12H10ClF3O3, was determined in order to establish the configuration of the C=double bond. The compound was found to be the Z isomer. The crystal structure is dominated by Cl⋯O halogen bonds [Cl⋯O = 3.111 (3) Å], as well as C—H⋯O and C—H⋯F hydrogen-bonding interactions, that connect neighboring molecules into a three-dimensional supramolecular network
In-Depth Assessment of the Palladium-Catalyzed Fluorination of Five-Membered Heteroaryl Bromides
A thorough investigation of the challenging Pd-catalyzed fluorination of five-membered heteroaryl bromides is presented. Crystallographic studies and density functional theory (DFT) calculations suggest that the challenging step of this transformation is C–F reductive elimination of five-membered heteroaryl fluorides from Pd(II) complexes. On the basis of these studies, we have found that various heteroaryl bromides bearing phenyl groups in the ortho position can be effectively fluorinated under catalytic conditions. Highly activated 2-bromoazoles, such as 8-bromocaffeine, are also viable substrates for this reaction.National Institutes of Health (U.S.) (GM46059)National Science Foundation (U.S.) (Predoctoral Fellowship 2010094243)Amgen Inc
(β-D-ribofuranosyl)formamidine in the design and synthesis of 2-(β-D-ribofuranosyl)pyrimidines, including RF-containing derivatives
A wide range of novel 2-(β-D-ribofuranosyl)pyrimidines, including RF-containing derivatives, have been synthesized by the reaction of (β-D-ribofuranosyl)formamidine with various dielectrophilic substrates such as 3-alkoxy- and 3-chloro-1-(polyfluoroalkyl)propen-1-ones, 3-nitro- and 3-(phenylethynyl)chromones and heteroaryl acetylenic ketones. Polyfluoroalkyl-containing 2-(β-D-ribofuranosyl)pyrimidine derivatives have been synthesized by the reaction of (β-D-ribofuranosyl)formamidine with dielectrophilic substrates such as 3-alkoxy- and 3-chloro-1-(polyfluoroalkyl) propen-1-ones, 3-nitro- and 3-(phenylethynyl)chromones and heteroaryl acetylenic ketones. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
High regioselectivity in electrochemical α-methoxylation of N-protected cyclic amines
N-Protecting groups of α-substituted cyclic amines strongly affected the regioselectivity in electrochemical methoxylation of these compounds. Namely, N-acyl derivatives were transformed into α′-methoxylated compounds, while N-cyano derivatives changed into α-methoxylated derivatives. Furthermore, Lewis acid catalyzed nucleophilic substitution of the α-methoxylated compounds protected with cyano group afforded α,α-disubstituted cyclic amines
Unsymmetrical Trifluoromethyl Methoxyphenyl β-Diketones: Effect of the Position of Methoxy Group and Coordination at Cu(II) on Biological Activity
Copper(II) complexes with 1,1,1-trifluoro-4-(4-methoxyphenyl)butan-2,4-dione (HL1) were synthesized and characterized by elemental analysis, FT-IR spectroscopy, and single crystal X-ray diffraction. The biological properties of HL1 and cis-[Cu(L1)2 (DMSO)] (3) were examined against Gram-positive and Gram-negative bacteria and opportunistic unicellular fungi. The cytotoxicity was estimated towards the HeLa and Vero cell lines. Complex 3 demonstrated antibacterial activity towards S. aureus comparable to that of streptomycin, lower antifungal activity than the ligand HL1 and moderate cytotoxicity. The bioactivity was compared with the activity of compounds of similar structures. The effect of changing the position of the methoxy group at the aromatic ring in the ligand moiety of the complexes on their antimicrobial and cytotoxic activity was explored. We propose that complex 3 has lower bioavailability and reduced bioactivity than expected due to strong intermolecular contacts. In addition, molecular docking studies provided theoretical information on the interactions of tested compounds with ribonucleotide reductase subunit R2, as well as the chaperones Hsp70 and Hsp90, which are important biomolecular targets for antitumor and antimicrobial drug search and design. The obtained results revealed that the complexes displayed enhanced affinity over organic ligands. Taken together, the copper(II) complexes with the trifluoromethyl methoxyphenyl-substituted β-diketones could be considered as promising anticancer agents with antibacterial properties. © 2021, MDPI. All rights reserved.This work was funded by RFBR and Sverdlovsk region (project numbers 20-43-660042 and 20-53-00006) and supported by the basic theme of the Russian Academy of Sciences (state registration no. AAAA-A19-119011790132-7 and project no. AAAA-A19-119012490006-1). XRD experiments and analytical studies were carried out using the equipment of the Center for Joint Use “Spectroscopy and Analysis of Organic Compounds” at the Postovsky Institute of Organic Synthesis UB RAS. X-ray study was supported by the U.S. National Science Foundation (Grant DMR-1523611 PREM). The cytotoxicity assay was carried out at the “Simbioz” Center for the Collective Use of Research Equipment in the Field of Physical–Chemical Biology and Nanobiotechnology at IBPPM RAS. This work has been supported by the RUDN University Strategic Academic Leadership Program
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