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Mateusz Dako Anna Doga Magdalena Siedzielnik Karol Biernacki Olga Ciupak Janusz Rachon Sebastian Demkowicz 《Molecules (Basel, Switzerland)》2021,26(13)
Herein, we present the synthesis and crystal structures determination of five 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives containing halogen atoms, 6a–e, which may be used as an excellent mimic of steroids in the drug development process. Good quality crystals obtained for all of the synthesized compounds allowed the analysis of their molecular structures. Subsequently, the determined crystal structures were used to calculate the Hirshfeld surfaces for each of the synthesized compounds. Furthermore, results of our docking studies indicated that synthesized derivatives are able to bind effectively to the active sites of selected enzymes and receptors involved in the hormone biosynthesis and signaling pathways, analogously to the native steroids. 相似文献
83.
Micha Magott Bartomiej Gawe Marcin Sarewicz Mateusz Reczyski Karolina Ogorzay Wacaw Makowski Dawid Pinkowicz 《Chemical science》2021,12(26):9176
While metal–organic frameworks (MOFs) are at the forefront of cutting-edge porous materials, extraordinary sorption properties can also be observed in Prussian Blue Analogs (PBAs) and related materials comprising extremely short bridging ligands. Herein, we present a bimetallic nonporous cyanide-bridged coordination polymer (CP) {[Mn(imH)]2[Mo(CN)8]}n (1Mn; imH = imidazole) that can efficiently and reversibly capture and release water molecules over tens of cycles without any fatigue despite being based on one of the shortest bridging ligands known – the cyanide. The sorption performance of {[Mn(imH)]2[Mo(CN)8]}n matches or even outperforms MOFs that are typically selected for water harvesting applications with perfect sorption reversibility and very low desorption temperatures. Water sorption in 1Mn is possible due to the breathing effect (accompanied by a dramatic cyanide-framework transformation) occurring in three well-defined steps between four different crystal phases studied structurally by X-ray diffraction structural analysis. Moreover, the capture of H2O by 1Mn switches the EPR signal intensity of the MnII centres, which has been demonstrated by in situ EPR measurements and enables monitoring of the hydration level of 1Mn by EPR. The sorption of water in 1Mn controls also its photomagnetic behavior at the cryogenic regime, thanks to the presence of the [MoIV(CN)8]4− photomagnetic chromophore in the structure. These observations demonstrate the extraordinary sorption potential of cyanide-bridged CPs and the possibility to merge it with the unique physical properties of this class of compounds arising from their bimetallic character (e.g. photomagnetism and long-range magnetic ordering).A cyanide-bridged coordination polymer {[Mn(imH)]2[Mo(CN)8]}n shows exceptional water sorption properties, very large breathing effect and outstanding stability – properties that are unique for this class of compounds – Prussian blue analogs. 相似文献
84.
Akhtar J Afzaal M Banski M Podhorodecki A Syperek M Misiewicz J Bangert U Hardman SJ Graham DM Flavell WR Binks DJ Gardonio S O'Brien P 《Journal of the American Chemical Society》2011,133(14):5602-5609
Truly alloyed PbS(x)Se(1-x) (x = 0-1) nanocrystals (~5 nm in size) have been prepared, and their resulting optical properties are red-shifted systematically as the sulfur content of the materials increases. Their optical properties are discussed using a modified Vegard's approach and the bowing parameter for these nanoalloys is reported for the first time. The alloyed structure of the nanocrystals is supported by the energy-filtered transmission electron microscope images of the samples, which show a homogeneous distribution of sulfur and selenium within the nanocrystals. X-ray photoelectron spectroscopy studies on ligand-exchanged nanocrystals confirmed the expected stoichiometry and various oxidized species. 相似文献
85.
M. Winnewisser E.F. Pearson J. Galica B.P. Winnewisser 《Journal of Molecular Spectroscopy》1982,91(1):255-268
The pure rotational spectrum of CH3CNO was measured in the frequency range 75 to 230 GHz. For the ground state, transitions were measured for J between 9 and 28 and for K from 0 to 12. In the v10 = 1 state the measurements range from J = 0 to 19 and from K = 0 to 11. Numerous perturbations are observed, apparently due to accidental resonances with levels in other vibrational states. The contributions due to ΔK = 2, Δl = 2 matrix elements (l-type resonance and l-type doubling) are accounted for by matrix diagonalization, and the effects due to accidental resonances are presented graphically. 相似文献
86.
Two new porphyrin-C60 dyads have been synthesized in which the electroactive moieties have been connected through a p-phenylenevinylene dimer. The electrochemical study confirms the amphoteric redox behavior of these dyads. Irradiation of these compounds gives rise to the corresponding radical pair confirming that substitution on the β-position of the porphyrin facilitates the electronic communication between the porphyrin and C60. 相似文献
87.
Gnichwitz JF Wielopolski M Hartnagel K Hartnagel U Guldi DM Hirsch A 《Journal of the American Chemical Society》2008,130(26):8491-8501
A series of novel supramolecular architectures were built around a tin tetraphenyl porphyrin platform 6--functionalized by a 2-fold 1-ethyl-3-3-(3-dimethylaminopropyl)carbodiimide (EDC) promoted condensation reaction--and chiral depsipeptide dendrons of different generations 1-4. Here, implementation of a Hamilton receptor provided the necessary means to keep the constituents together via strong hydrogen bonding. Characterization of all architectures has been performed, including 4 which is the fourth generation, on the basis of NMR and photophysical methods. In particular, several titration experiments were conducted suggesting positive cooperativity, an assessment that is based on association constants that tend to be higher for the second binding step than for the first step. Importantly, molecular modeling calculations reveal a significant deaggregation of the intermolecular network of 6 during the course of the first binding step. As a consequence, an improved accessibility of the second Hamilton receptor unit in 6 emerges and, in turn, facilitates the higher association constants. The features of the equilibrium, that is, the dynamic exchange of depsipeptide dendrons 1-4 with fullerene 5, was tested in photophysical reference experiments. These steady-state and time-resolved measurements showed the tunable excited-state deactivations of these complexes upon photoexcitation. 相似文献
88.
Stanisaw Krompiec Robert Penczek Mateusz Penkala Micha Krompiec Jzef Rzepa Marek Matlengiewicz Joanna Jaworska Stefan Baj 《Journal of molecular catalysis. A, Chemical》2008,290(1-2):15-22
Addition of alcohols and phenols to allyl ethers catalyzed mainly by ruthenium complexes was studied. Complexes of ruthenium generated in situ from precursors such as {[RuCl2(1,5-COD)]x} or [Ru3(CO)12] and from external ligands such as phosphines (e.g. PPh3, PBu3, BINAP) or phosphites (e.g. P(OPh)3, P(OMe)3) were found to be particularly efficient catalysts of the studied reactions. Transacetalization reaction could be practically completely eliminated by the addition of a base (particularly Na2CO3) to the catalytic systems. It was observed that the selectivity of mixed acetals formation increases with increasing value of Θ parameter of phosphines. Especially interesting results (0–5% of transacetalization) have been obtained for catalytic systems generated from {[RuCl2(1,5-COD)]x} or [Ru3(CO)12], phosphines (PPh3, BINAP, dppe, tris(2,4,6-tri-metylphenyl)phosphine, or dppf) and Na2CO3. The mechanism of mixed acetals formation has been investigated using deuterated reagents. It is postulated that the examined reaction is a nucleophilic addition of ROH to a hydrido-π-allyl complex formed during oxidative addition of allyl substrate to metal complex. As a result, a new, selective, and convenient method of the synthesis of symmetrical and, in particular, unsymmetrical (mixed) acetals has been developed. Mixed acetals CH3CH2CH(OR1)(OR2) may be obtained in the reaction of R1-O-allyl with R2OH or R1OH with R2-O-allyl, depending on the structure of R1 and R2. 相似文献
89.
Kuprianowicz Mateusz Kaźmierczak Marcin Wójtowicz-Rajchel Hanna 《Structural chemistry》2016,27(4):1265-1278
A series of fused isoxazolidines have been prepared via 1,3-dipolar cycloaddition reactions of N-protected methylenenitrones with 1,3-dimethyluracil derivatives, and their NMR spectra have been recorded in TFA-d and in CDCl3 over a wide range of temperatures. The spectra indicate the presence of two invertomers for all isoxazolidines. Barriers to nitrogen inversion in the cycloadduct 6a have been determined using DFT quantochemical calculations. Our estimates have shown that the inversion proceeds at more complex path, involving four structures of local minima and four transition states.
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