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51.
Gonec T Bobal P Sujan J Pesko M Guo J Kralova K Pavlacka L Vesely L Kreckova E Kos J Coffey A Kollar P Imramovsky A Placek L Jampilek J 《Molecules (Basel, Switzerland)》2012,17(1):613-644
In this study, a series of thirty-five substituted quinoline-2-carboxamides and thirty-three substituted naphthalene-2-carboxamides were prepared and characterized. They were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four mycobacterial species. N-Cycloheptylquinoline-2-carboxamide, N-cyclohexylquinoline-2-carboxamide and N-(2-phenylethyl)quinoline-2-carboxamide showed higher activity against M. tuberculosis than the standards isoniazid or pyrazinamide and 2-(pyrrolidin-1-ylcarbonyl)quinoline and 1-(2-naphthoyl)pyrrolidine expressed higher activity against M. kansasii and M. avium paratuberculosis than the standards isoniazid or pyrazinamide. The most effective antimycobacterial compounds demonstrated insignificant toxicity against the human monocytic leukemia THP-1 cell line. The PET-inhibiting activity expressed by IC(50) value of the most active compound N-benzyl-2-naphthamide was 7.5 μmol/L. For all compounds, the structure-activity relationships are discussed. 相似文献
52.
Böhrsch V Mathew T Zieringer M Vallée MR Artner LM Dernedde J Haag R Hackenberger CP 《Organic & biomolecular chemistry》2012,10(30):6211-6216
In this paper we present the synthesis of glyco-phosphoramidate conjugates as easily accessible analogs of glyco-phosphorous esters via the Staudinger-phosphite reaction. This protocol takes advantage of synthetically accessible symmetrical carbohydrate phosphites in good overall yields, in which ethylene or propylene linkers can be introduced between phosphorous and galactose or lactose moieties. The phosphites were finally applied for the chemoselective reaction with azido-peptides and polyazido(poly)glycerols. 相似文献
53.
Georg Steinhauser Gerald Giester Christoph Wagner Nicolae Leopold Johannes H. Sterba Bernhard Lendl Max Bichler 《Helvetica chimica acta》2009,92(7):1371-1384
A set of N‐rich salts, 3 – 9 , of the heavy lanthanoids (terbium, 3 ; dysprosium, 4 ; holmium 5 ; erbium, 6 ; thulium, 7 ; ytterbium, 8 ; lutetium, 9 ) based on the energetic 5,5′‐azobis[1H‐tetrazole] (H2ZT) was synthesized and characterized by elemental analysis, vibrational (IR and Raman) spectroscopy, and X‐ray structure determination. The synthesis of the lanthanoid salts 3 – 9 was performed by crystallization from concentrated aqueous solutions of disodium 5,5′‐azobis[1H‐tetrazol‐1‐ide] dihydrate (Na2ZT?2 H2O; 1 ) and the respective Ln(NO3)3?5 H2O and yielded large rhombic crystals of the type [Ln(H2O)8]2(ZT)3?6 H2O in ca. 70% of the theoretical yield. The compounds 3 – 9 are isostructural (triclinic space group P ) to the previously published yttrium salt 2 ; they show, however, a clear lanthanoid contraction of several crystallographic parameters, e.g., the cell volume or the Ln? O bond lengths of the Ln3+ ions and the coordinating H2O molecules. The lanthanoid contraction influences the strengths of the H‐bonds, which can be observed as a red shift by 4 cm?1 in the characteristic IR band, in particular from 3595 cm?1 ( 3 ) to 3599 cm?1 ( 9 ). In good agreement with previous works, 2 – 9 are purely salt‐like compounds without a coordinative bond between the tetrazolide anion and the Ln3+ cation. 相似文献
54.
Zechao Yang Lukas Fromm Tim Sander Julian Gebhardt Tobias A. Schaub Andreas Grling Milan Kivala Sabine Maier 《Angewandte Chemie (International ed. in English)》2020,59(24):9549-9555
Demonstrated here is a supramolecular approach to fabricate highly ordered monolayered hydrogen‐ and halogen‐bonded graphyne‐like two‐dimensional (2D) materials from triethynyltriazine derivatives on Au(111) and Ag(111). The 2D networks are stabilized by N???H?C(sp) bonds and N???Br?C(sp) bonds to the triazine core. The structural properties and the binding energies of the supramolecular graphynes have been investigated by scanning tunneling microscopy in combination with density‐functional theory calculations. It is revealed that the N???Br?C(sp) bonds lead to significantly stronger bonded networks compared to the hydrogen‐bonded networks. A systematic analysis of the binding energies of triethynyltriazine and triethynylbenzene derivatives further demonstrates that the X3‐synthon, which is commonly observed for bromobenzene derivatives, is weaker than the X6‐synthon for our bromotriethynyl derivatives. 相似文献
55.
56.
Jan Tauchen Lukas Huml Ludvik Bortl Ivo Doskocil Veronika Jarosova Petr Marsik 《Natural product research》2019,33(18):2718-2721
Plants mentioned in this study have numerous records in traditional Peruvian medicine being used in treatment of cancer and other diseases likely to be associated with oxidative stress. Amongst the eight plant species tested, only Dysphania ambrosioides exhibited combinatory antioxidant and anti-proliferative effect on a broad spectrum of cancer cells (DPPH and ORAC values = 80.6 and 687.3 μg TE/mg extract, respectively; IC50 against Caco-2, HT-29 and Hep-G2 = 129.2, 69.9 and 130.6, respectively). Alkaloids and phenolic compounds might significantly contribute to anticancer/antioxidant activity of this plant. The results justify the traditional medicinal use of this plant. Our findings further suggest that D. ambrosioides might serve as a prospective material for further development of novel plant-based antioxidant and/or anti-proliferative agents. Detailed analysis of chemical composition together with toxicology assessments and in vivo antioxidant/anti-proliferative activity of this plant should be carried out in order to verify its potential practical use. 相似文献
57.
Yann K. Petit Christian Leypold Nika Mahne Elonore Mourad Lukas Schafzahl Christian Slugovc Sergey M. Borisov Stefan A. Freunberger 《Angewandte Chemie (International ed. in English)》2019,58(20):6535-6539
Singlet oxygen (1O2) causes a major fraction of the parasitic chemistry during the cycling of non‐aqueous alkali metal‐O2 batteries and also contributes to interfacial reactivity of transition‐metal oxide intercalation compounds. We introduce DABCOnium, the mono alkylated form of 1,4‐diazabicyclo[2.2.2]octane (DABCO), as an efficient 1O2 quencher with an unusually high oxidative stability of ca. 4.2 V vs. Li/Li+. Previous quenchers are strongly Lewis basic amines with too low oxidative stability. DABCOnium is an ionic liquid, non‐volatile, highly soluble in the electrolyte, stable against superoxide and peroxide, and compatible with lithium metal. The electrochemical stability covers the required range for metal–O2 batteries and greatly reduces 1O2 related parasitic chemistry as demonstrated for the Li–O2 cell. 相似文献
58.
Lukas Fischer Alexander K. Strzelczyk Nils Wedler Christian Kropf Stephan Schmidt Laura Hartmann 《Chemical science》2020,11(36):9919
Catechol and amine residues, both abundantly present in mussel adhesion proteins, are known to act cooperatively by displacing hydration barriers before binding to mineral surfaces. In spite of synthetic efforts toward mussel-inspired adhesives, the effect of positioning of the involved functional groups along a polymer chain is not well understood. By using sequence-defined oligomers grafted to soft hydrogel particles as adhesion probes, we study the effect of catechol–amine spacing, as well as positioning relative to the oligomer terminus. We demonstrate that the catechol–amine spacing has a significant effect on adhesion, while shifting their position has a small effect. Notably, combinations of non-charged amides and catechols can achieve similar cooperative effects on adhesion when compared to amine and catechol residues. Thus, these findings provide a blueprint for the design of next generation mussel-inspired adhesives.The catechol driven adhesion of precision macromolecules on glass surfaces is quantified by soft colloidal probe readout. Catechol moieties are shown to synergize with amine and amide residues depending on residue spacing and residue order. 相似文献
59.
Lukas Spree Christin Schlesier Dr. Aram Kostanyan Dr. Rasmus Westerström Prof. Dr. Thomas Greber Prof. Dr. Bernd Büchner Dr. Stanislav M. Avdoshenko Dr. Alexey A. Popov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(11):2436-2449
The substitution of scandium in fullerene single-molecule magnets (SMMs) DySc2N@C80 and Dy2ScN@C80 by lutetium has been studied to explore the influence of the diamagnetic metal on the SMM performance of dysprosium nitride clusterfullerenes. The use of lutetium led to an improved SMM performance of DyLu2N@C80, which shows a higher blocking temperature of magnetization (TB=9.5 K), longer relaxation times, and broader hysteresis than DySc2N@C80 (TB=6.9 K). At the same time, Dy2LuN@C80 was found to have a similar blocking temperature of magnetization to Dy2ScN@C80 (TB=8 K), but substantially different interactions between the magnetic moments of the dysprosium ions in the Dy2MN clusters. Surprisingly, although the intramolecular dipolar interactions in Dy2LuN@C80 and Dy2ScN@C80 are of similar strength, the exchange interactions in Dy2LuN@C80 are close to zero. Analysis of the low-frequency molecular and lattice vibrations showed strong mixing of the lattice modes and endohedral cluster librations in k-space. This mixing simplifies the spin–lattice relaxation by conserving the momentum during the spin flip and helping to distribute the moment and energy further into the lattice. 相似文献
60.
Florian Ritter Dr. Lukas John Dr. Tobias Schindler Julian P. Schroers Simon Teeuwen Dr. Michael E. Tauchert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(59):13436-13444
The dative Pd→B interaction in a series of RDPBR’ Pd0 and PdII complexes (RDPBR’=(o-PR2C6H4)2BR’, diphosphinoborane) was analyzed using XRD, 11B NMR spectroscopy and NBO/NLMO calculations. The borane acceptor discriminates between the oxidation state PdII and Pd0, stabilizing the latter. Reaction of lithium amides with [(RDPBR’)PdII(4-NO2C6H4)I] chemoselectively yields the C−N coupling product. DFT modelling indicates no significant impact of PdII→B coordination on the inner-sphere reductive elimination rate. 相似文献