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931.
Areenan In-Iam Dr. Markus Wolf Dr. Claudia Wilfer Prof. Dr. Dominik Schaniel Prof. Dr. Theo Woike Prof. Dr. Peter Klüfers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(5):1304-1325
Mononitrosyl–iron compounds (MNICs) of the Enemark–Feltham {FeNO}7 type can be divided into a doublet (S=1/2) and a quartet (S=3/2) spin variant. The latter relies on weak-field co-ligands such as amine carboxylates. Aqua-only co-ligation appears to exist in the long-known “brown-ring” [Fe(H2O)5(NO)]2+ cation, which was prepared originally from ferrous salts and NO in sulfuric acid. A chloride variant of this species, the green [FeCl3(NO)]− ion, was first prepared analoguosly by using hydrochloric instead of sulfuric acid. As a tetrahedral species, it is the simple prototype of sulfur-bonded {FeNO}7 (S=3/2) MNICs of biological significance. Although it has been investigated for more than a century, neither clean preparative routes nor reliable structural parameters were available for the [FeCl3(NO)]− ion and related species such as the [FeCl2(NO)2]− ion, a prototypical dinitrosyliron species (a “DNIC”). In this work, both issues have been resolved. In addition, we report on a computational study on the ground- and excited-state properties including an assignment of the chromophoric transitions. Photoinduced metastable isomers were characterised in a combined experimental and computational approach that resulted in the confirmation of a single photoinduced linkage isomer of the paramagnetic nitrosyl–metal coordination entity. 相似文献
932.
Moritz F. Kuehnel Charles E. Creissen Constantin D. Sahm Dominik Wielend Anja Schlosser Katherine L. Orchard Erwin Reisner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):5113-5117
A precious‐metal‐ and Cd‐free photocatalyst system for efficient H2 evolution from aqueous protons with a performance comparable to Cd‐based quantum dots is presented. Rod‐shaped ZnSe nanocrystals (nanorods, NRs) with a Ni(BF4)2 co‐catalyst suspended in aqueous ascorbic acid evolve H2 with an activity up to 54±2 mmol gZnSe?1 h?1 and a quantum yield of 50±4 % (λ=400 nm) under visible light illumination (AM 1.5G, 100 mW cm?2, λ>400 nm). Under simulated full‐spectrum solar irradiation (AM 1.5G, 100 mW cm?2), up to 149±22 mmol gZnSe?1 h?1 is generated. Significant photocorrosion was not noticeable within 40 h and activity was even observed without an added co‐catalyst. The ZnSe NRs can also be used to construct an inexpensive delafossite CuCrO2 photocathode, which does not rely on a sacrificial electron donor. Immobilized ZnSe NRs on CuCrO2 generate photocurrents of around ?10 μA cm?2 in an aqueous electrolyte solution (pH 5.5) with a photocurrent onset potential of approximately +0.75 V vs. RHE. This work establishes ZnSe as a state‐of‐the‐art light absorber for photocatalytic and photoelectrochemical H2 generation. 相似文献
933.
934.
Nethmi De&#x;Alwis&#x;Watuthanthrige Michael L. Allegrezza Madison T. Dolan Alex J. Kloster Marina Kovaliov Saadyah Averick Dominik Konkolewicz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):11952-11955
The power of chemical light generation (chemiluminescence) is used to drive polymerization reactions. A biphasic reaction is developed such that light‐generating reactions are confined to the organic phase and photopolymerization occurs in the aqueous phase. Well‐defined RAFT‐capped polymers are synthesized and the kinetics are shown to be dictated by light generation. 相似文献
935.
Dr. Hans-Georg Lerchen Dr. Beatrix Stelte-Ludwig Dr. Sandra Berndt Dr. Anette Sommer Dr. Lisa Dietz Dr. Anne-Sophie Rebstock Dr. Sarah Johannes Dr. Leo Marx Dr. Hannah Jörißen Dr. Christoph Mahlert Simone Greven 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(35):8208-8213
Many antibody–drug conjugates (ADCs) have failed to achieve a sufficient therapeutic window in clinical studies either due to target-mediated or off-target toxicities. To achieve an additional safety level, a new class of antibody–prodrug conjugates (APDCs) directed against different targets in solid tumors is here described. The tumor-associated lysosomal endopeptidase legumain with a unique cleavage sequence was utilized for APDC metabolism. Legumain-activatable APDCs were as potent as their cathepsin B-activatable analogues. The peptide sequence susceptible to legumain cleavage was optimized for further discrimination of the formation of active metabolites within tumor cells versus healthy tissues, leveraging different tissue-specific legumain activities. Optimized APDCs with slow legumain-mediated conversion reduced preclinically the levels of active metabolite in healthy organs while retaining high activity against different TWEAKR- and B7H3-expressing tumors. 相似文献
936.
Eric Siemes Oleksii Nevskyi Dr. Dmytro Sysoiev Sarah K. Turnhoff Alex Oppermann Dr. Thomas Huhn Prof. Dr. Walter Richtering Prof. Dr. Dominik Wöll 《Angewandte Chemie (International ed. in English)》2018,57(38):12280-12284
The in situ nanoscopic imaging of soft matter polymer structures is of importance to gain knowledge of the relationship between structure, properties, and functionality on the nanoscopic scale. Cross‐linking of polymer chains effects the viscoelastic properties of gels. The correlation of mechanical properties with the distribution and amount of cross‐linkers is relevant for applications and for a detailed understanding of polymers on the molecular scale. We introduce a super‐resolution fluorescence‐microscopy‐based method for visualizing and quantifying cross‐linker points in polymer systems. A novel diarylethene‐based photoswitch with a highly fluorescent closed and a non‐fluorescent open form is used as a photoswitchable cross‐linker in a polymer network. As an example for its capability to nanoscopically visualize cross‐linking, we investigate pNIPAM microgels as a system known with variations in internal cross‐linking density. 相似文献
937.
Dominik L. Pastoetter Dr. Yannan Liu Dr. Matthew A. Addicoat Dr. Silvia Paasch Dr. Arezoo Dianat David Bodesheim Albrecht L. Waentig Dr. Shunqi Xu Mino Borrelli Dr. Alexander Croy Dr. Marcus Richter Prof. Dr. Eike Brunner Prof. Dr. Gianaurelio Cuniberti Prof. Dr. Xinliang Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(20):e202104502
The interest in two-dimensional conjugated polymers (2D CPs) has increased significantly in recent years. In particular, vinylene-linked 2D CPs with fully in-plane sp2-carbon-conjugated structures, high thermal and chemical stability, have become the focus of attention. Although the Horner-Wadsworth-Emmons (HWE) reaction has been recently demonstrated in synthesizing vinylene-linked 2D CPs, it remains largely unexplored due to the challenge in synthesis. In this work, we reveal the control of crystallinity of 2D CPs during the solvothermal synthesis of 2D-poly(phenylene-quinoxaline-vinylene)s (2D-PPQVs) and 2D-poly(phenylene-vinylene)s through the HWE polycondensation. The employment of fluorinated phosphonates and rigid aldehyde building blocks is demonstrated as crucial factors in enhancing the crystallinity of the obtained 2D CPs. Density functional theory (DFT) calculations reveal the critical role of the fluorinated phosphonate in enhancing the reversibility of the (semi)reversible C−C single bond formation. 相似文献
938.
Dr. Inês C. B. Martins Dominik Al-Sabbagh Dr. Ursula Bentrup Dr. Julien Marquardt Dr. Thomas Schmid Dr. Ernesto Scoppola Werner Kraus Dr. Tomasz M. Stawski Dr. Ana Guilherme Buzanich Dr. Kirill V. Yusenko Dr. Steffen Weidner Dr. Franziska Emmerling 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(27):e202200079
A new hetero-bimetallic polyoxometalate (POM) nano-ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO8] cubes. The nano-ring is formed via self-assembly from metal precursors in aqueous acidic medium. The compound (NH4)16[(BiPMo11O39)4] ⋅ 22 H2O; (P4Bi4Mo44) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry mass spectrometry (TG-DSC-MS). The formation of the nano-ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo−K and the Bi−L3 edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi−Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure. 相似文献
939.
Katarzyna Pokajewicz Marietta Bia&#x;o&#x; Liudmyla Svydenko Nataliia Hudz Rados&#x;aw Balwierz Dominik Marciniak Piotr Pawe&#x; Wieczorek 《Molecules (Basel, Switzerland)》2022,27(7)
New cultivars of lavender adapted to arid steppe conditions were developed by the Institute of Rice of Ukrainian National Academy of Agrarian Sciences (NAAS). This work is a part of the characterization process of the new cultivars. The chemical composition of the essential oil of the seven new Lavandula angustifolia and eight new Lavandula x intermedia cultivars was investigated and compared. In total, 71 different compounds were identified. Linalool and linalool acetate were the main components in both species in ranges of 26.14–57.07% and 9.08–24.45%, respectively. They were followed by terpinen-4-ol (2.16–22.44%), lavandulyl acetate (2.12–10.23%), and lavandulol (1.30–3.14) in the case of L. angustifolia and camphor (10.11–12.55%), borneol (5.49–8.71%), and eucalyptol (0.47–7.41%) in the case of L. x intermedia. The oils had a valuable terpene profile—a high linalool content and the substantial presence of lavandulol and its ester. Nevertheless, they did not comply with the industry standards, mostly due to high levels of terpinene-4-ol. Evidently, a high content of terpinen-4-ol is a characteristic feature of L. angustifolia oils bred in Ukraine. Additionally, the LA3 cultivar yielded an oil with some of the highest linalool contents reported in the literature. Statistical analysis and literature data allowed for the comparative analysis of the gathered data. MANOVA, PCA, and HCA marked caryophyllene oxide as another potential differentiating compound between studied species. 相似文献
940.
Wojciech Golimowski Miros&#x;awa Teleszko Damian Marcinkowski Dominik Kmiecik Anna Grygier Andrzej Kwa nica 《Molecules (Basel, Switzerland)》2022,27(10)
In the last decade, the demand for edible niche oils has increased. Therefore, the aim of this study was to characterize the seeds hemp (Cannabis sativa L.) varieties: ‘Finola’ (FIN-314)’, ‘Earlina 8FC’, and ‘Secuieni Jubileu’, and cold and hot pressed oils were prepared from each seed. The seeds were examined for moisture content, granulometric distribution, bulk density, and fat content. Seeds were pressed without and with preconditioning (60 °C), and oil yield and pressing time were recorded. The oil was filtered through cellulose membranes. Oil–water content, oil color, fatty acid profile, and sterol content were studied. From the study conducted, there are significant differences in the parameters of oil recovery and its quality compared to ‘Finola’ seed oil, which is widely reported in the literature. ‘Finola’ oil yield was the lowest, with an average of 79% compared to ‘Earlina’ (82%) and ‘S. Jubileu’ (84%). All oil samples contained a comparable amount of sterols, with campesterol (0.32 mg/g), β-sitosterol (1.3 mg/g) and Δ5-avenasterol (0.15 mg/g) predominating. From the organoleptic evaluation, it was evident that both varieties hemp oils and marc (‘Earlina’ and ‘S. Jubileu’) were not bitter like the “Finola” oil and marc. More detailed studies in this direction have to be undertaken. 相似文献