@article{ZimniakKirschnerHilpertetal.2021, author = {Zimniak, Melissa and Kirschner, Luisa and Hilpert, Helen and Geiger, Nina and Danov, Olga and Oberwinkler, Heike and Steinke, Maria and Sewald, Katherina and Seibel, J{\"u}rgen and Bodem, Jochen}, title = {The serotonin reuptake inhibitor Fluoxetine inhibits SARS-CoV-2 in human lung tissue}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, doi = {10.1038/s41598-021-85049-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259820}, pages = {5890}, year = {2021}, abstract = {To circumvent time-consuming clinical trials, testing whether existing drugs are effective inhibitors of SARS-CoV-2, has led to the discovery of Remdesivir. We decided to follow this path and screened approved medications "off-label" against SARS-CoV-2. Fluoxetine inhibited SARS-CoV-2 at a concentration of 0.8 mu g/ml significantly in these screenings, and the EC50 was determined with 387 ng/ml. Furthermore, Fluoxetine reduced viral infectivity in precision-cut human lung slices showing its activity in relevant human tissue targeted in severe infections. Fluoxetine treatment resulted in a decrease in viral protein expression. Fluoxetine is a racemate consisting of both stereoisomers, while the S-form is the dominant serotonin reuptake inhibitor. We found that both isomers show similar activity on the virus, indicating that the R-form might specifically be used for SARS-CoV-2 treatment. Fluoxetine inhibited neither Rabies virus, human respiratory syncytial virus replication nor the Human Herpesvirus 8 or Herpes simplex virus type 1 gene expression, indicating that it acts virus-specific. Moreover, since it is known that Fluoxetine inhibits cytokine release, we see the role of Fluoxetine in the treatment of SARS-CoV-2 infected patients of risk groups.}, language = {en} } @article{ZhangRadackiBraunschweigetal.2021, author = {Zhang, Fangyuan and Radacki, Krzysztof and Braunschweig, Holger and Lambert, Christoph and Ravat, Prince}, title = {Zinc-[7]helicenocyanine and its discrete π-stacked homochiral Dimer}, series = {Angewandte Chemie International Edition}, volume = {60}, journal = {Angewandte Chemie International Edition}, doi = {10.1002/anie.202109380}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256534}, pages = {23656-23660}, year = {2021}, abstract = {In this communication, we demonstrate a novel approach to prepare a discrete dimer of chiral phthalocyanine (Pc) by exploiting the flexible molecular geometry of helicenes, which enables structural interlocking and strong aggregation tendency of Pcs. Synthesized [7]helicene-Pc hybrid molecular structure, zinc-[7]helicenocyanine (Zn-7HPc), exclusively forms a stable dimeric pair consisting of two homochiral molecules. The dimerization constants were estimated to be as high as 8.96×10\(^6\) M\(^{-1}\) and 3.42×107 M\(^{-1}\) in THF and DMSO, respectively, indicating remarkable stability of dimer. In addition, Zn\(^{-7}\)HPc exhibited chiral self-sorting behavior, which resulted in preferential formation of a homochiral dimer also in the racemic sample. Two phthalocyanine subunits in the dimeric form strongly communicate with each other as revealed by a large comproportionation constant and observation of an IV-CT band for the thermodynamically stable mixed-valence state.}, language = {en} } @article{ZhangMichailSaaletal.2019, author = {Zhang, Fangyuan and Michail, Evripidis and Saal, Fridolin and Krause, Ana-Maria and Ravat, Prince}, title = {Stereospecific Synthesis and Photophysical Properties of Propeller-Shaped C\(_{90}\)H\(_{48}\) PAH}, series = {Chemistry - A European Journal}, volume = {25}, journal = {Chemistry - A European Journal}, number = {71}, doi = {10.1002/chem.201904962}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-208682}, pages = {16241-16245}, year = {2019}, abstract = {Herein, we have synthesized an enantiomerically pure propeller-shaped PAH, C\(_{90}\)H\(_{48}\), possessing three [7]helicene and three [5]helicene subunits. This compound can be obtained in gram quantities in a straightforward manner. The photophysical and chiroptical properties were investigated using UV/Vis absorption and emission, optical rotation and circular dichroism spectroscopy, supported by DFT calculations. The nonlinear optical properties were investigated by two-photon absorption measurements using linearly and circularly polarized light. The extremely twisted structure and packing of the homochiral compound were investigated by single-crystal X-ray diffraction analysis.}, language = {en} } @article{ZahranAlbohyKhaliletal.2020, author = {Zahran, Eman Maher and Albohy, Amgad and Khalil, Amira and Ibrahim, Alyaa Hatem and Ahmed, Heba Ali and El-Hossary, Ebaa M. and Bringmann, Gerhard and Abdelmohsen, Usama Ramadan}, title = {Bioactivity Potential of Marine Natural Products from Scleractinia-Associated Microbes and In Silico Anti-SARS-COV-2 Evaluation}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {12}, issn = {1660-3397}, doi = {10.3390/md18120645}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220041}, year = {2020}, abstract = {Marine organisms and their associated microbes are rich in diverse chemical leads. With the development of marine biotechnology, a considerable number of research activities are focused on marine bacteria and fungi-derived bioactive compounds. Marine bacteria and fungi are ranked on the top of the hierarchy of all organisms, as they are responsible for producing a wide range of bioactive secondary metabolites with possible pharmaceutical applications. Thus, they have the potential to provide future drugs against challenging diseases, such as cancer, a range of viral diseases, malaria, and inflammation. This review aims at describing the literature on secondary metabolites that have been obtained from Scleractinian-associated organisms including bacteria, fungi, and zooxanthellae, with full coverage of the period from 1982 to 2020, as well as illustrating their biological activities and structure activity relationship (SAR). Moreover, all these compounds were filtered based on ADME analysis to determine their physicochemical properties, and 15 compounds were selected. The selected compounds were virtually investigated for potential inhibition for SARS-CoV-2 targets using molecular docking studies. Promising potential results against SARS-CoV-2 RNA dependent RNA polymerase (RdRp) and methyltransferase (nsp16) are presented.}, language = {en} } @article{WuerthnerNoll2021, author = {W{\"u}rthner, Frank and Noll, Niklas}, title = {A Calix[4]arene-Based Cyclic Dinuclear Ruthenium Complex for Light-Driven Catalytic Water Oxidation}, series = {Chemistry - A European Journal}, volume = {27}, journal = {Chemistry - A European Journal}, number = {1}, doi = {10.1002/chem.202004486}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230030}, pages = {444-450}, year = {2021}, abstract = {A cyclic dinuclear ruthenium(bda) (bda: 2,2'-bipyridine-6,6'-dicarboxylate) complex equipped with oligo(ethylene glycol)-functionalized axial calix[4]arene ligands has been synthesized for homogenous catalytic water oxidation. This novel Ru(bda) macrocycle showed significantly increased catalytic activity in chemical and photocatalytic water oxidation compared to the archetype mononuclear reference [Ru(bda)(pic)\(_2\)]. Kinetic investigations, including kinetic isotope effect studies, disclosed a unimolecular water nucleophilic attack mechanism of this novel dinuclear water oxidation catalyst (WOC) under the involvement of the second coordination sphere. Photocatalytic water oxidation with this cyclic dinuclear Ru complex using [Ru(bpy)\(_3\)]Cl\(_2\) as a standard photosensitizer revealed a turnover frequency of 15.5 s\(^{-1}\) and a turnover number of 460. This so far highest photocatalytic performance reported for a Ru(bda) complex underlines the potential of this water-soluble WOC for artificial photosynthesis.}, language = {en} } @article{WuerthnerMezaChinchaSchindleretal.2021, author = {W{\"u}rthner, Frank and Meza-Chincha, Ana-Lucia and Schindler, Dorothee and Natali, Mirco}, title = {Effects of Photosensitizers and Reaction Media on Light-Driven Water Oxidation with Trinuclear Ruthenium Macrocycles}, series = {ChemPhotoChem}, volume = {5}, journal = {ChemPhotoChem}, number = {2}, doi = {10.1002/cptc.202000133}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230116}, pages = {173-183}, year = {2021}, abstract = {Photocatalytic water oxidation is a promising process for the production of solar fuels and the elucidation of factors that influence this process is of high significance. Thus, we have studied in detail light-driven water oxidation with a trinuclear Ru(bda) (bda: 2,2'-bipyridine-6,6'-dicarboxylate) macrocycle MC3 and its highly water soluble derivative m-CH\(_2\)NMe\(_2\)-MC3 using a series of ruthenium tris(bipyridine) complexes as photosensitizers under varied reaction conditions. Our investigations showed that the catalytic activities of these Ru macrocycles are significantly affected by the choice of photosensitizer (PS) and reaction media, in addition to buffer concentration, light intensity and concentration of the sensitizer. Our steady-state and transient spectroscopic studies revealed that the photocatalytic performance of trinuclear Ru(bda) macrocycles is not limited by their intrinsic catalytic activities but rather by the efficiency of photogeneration of oxidant PS\(^+\) and its ability to act as an oxidizing agent to the catalysts as both are strongly dependent on the choice of photosensitizer and the amount of employed organic co-solvent.}, language = {en} } @article{WaechtlerKuebelBarthelmesetal.2016, author = {W{\"a}chtler, Maria and K{\"u}bel, Joachim and Barthelmes, Kevin and Winter, Andreas and Schmiedel, Alexander and Pascher, Torbj{\"o}rn and Lambert, Christoph and Schubert, Ulrich S. and Dietzek, Benjamin}, title = {Energy transfer and formation of long-lived \(^3\)MLCT states in multimetallic complexes with extended highly conjugated bis-terpyridyl ligands}, series = {Physical Chemistry Chemical Physics}, volume = {18}, journal = {Physical Chemistry Chemical Physics}, number = {4}, doi = {10.1039/c5cp04447b}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-191041}, pages = {2350-2360}, year = {2016}, abstract = {Multimetallic complexes with extended and highly conjugated bis-2,2':6',2''-terpyridyl bridging ligands, which present building blocks for coordination polymers, are investigated with respect to their ability to act as light-harvesting antennae. The investigated species combine Ru(II)- with Os(II)- and Fe(II)-terpyridyl chromophores, the latter acting as energy sinks. Due to the extended conjugated system the ligands are able to prolong the lifetime of the \(^3\)MLCT states compared to unsubstituted terpyridyl species by delocalization and energetic stabilization of the \(^3\)MLCT states. This concept is applied for the first time to Fe(II) terpyridyl species and results in an exceptionally long lifetime of 23 ps for the Fe(II) \(^3\)MLCT state. While partial energy (>80\%) transfer is observed between the Ru(II) and Fe(II) centers with a time-constant of 15 ps, excitation energy is transferred completely from the Ru(II) to the Os(II) center within the first 200 fs after excitation.}, language = {en} } @article{WuRoldaoRauchetal.2022, author = {Wu, Zhu and Roldao, Juan Carlos and Rauch, Florian and Friedrich, Alexandra and Ferger, Matthias and W{\"u}rthner, Frank and Gierschner, Johannes and Marder, Todd B.}, title = {Pure Boric Acid Does Not Show Room-Temperature Phosphorescence (RTP)}, series = {Angewandte Chemie}, volume = {61}, journal = {Angewandte Chemie}, number = {15}, doi = {10.1002/anie.202200599}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318308}, year = {2022}, abstract = {Boric acid (BA) has been used as a transparent glass matrix for optical materials for over 100 years. However, recently, apparent room-temperature phosphorescence (RTP) from BA (crystalline and powder states) was reported (Zheng et al., Angew. Chem. Int. Ed. 2021, 60, 9500) when irradiated at 280 nm under ambient conditions. We suspected that RTP from their BA sample was induced by an unidentified impurity. Our experimental results show that pure BA synthesized from B(OMe)\(_{3}\) does not luminesce in the solid state when irradiated at 250-400 nm, while commercial BA indeed (faintly) luminesces. Our theoretical calculations show that neither individual BA molecules nor aggregates would absorb light at >175 nm, and we observe no absorption of solid pure BA experimentally at >200 nm. Therefore, it is not possible for pure BA to be excited at >250 nm even in the solid state. Thus, pure BA does not display RTP, whereas trace impurities can induce RTP.}, language = {en} } @article{WuDinkelbachKerneretal.2022, author = {Wu, Zhu and Dinkelbach, Fabian and Kerner, Florian and Friedrich, Alexandra and Ji, Lei and Stepanenko, Vladimir and W{\"u}rthner, Frank and Marian, Christel M. and Marder, Todd B.}, title = {Aggregation-Induced Dual Phosphorescence from (o-Bromophenyl)-Bis(2,6-Dimethylphenyl)Borane at Room Temperature}, series = {Chemistry—A European Journal}, volume = {28}, journal = {Chemistry—A European Journal}, number = {30}, doi = {10.1002/chem.202200525}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-318297}, year = {2022}, abstract = {Designing highly efficient purely organic phosphors at room temperature remains a challenge because of fast non-radiative processes and slow intersystem crossing (ISC) rates. The majority of them emit only single component phosphorescence. Herein, we have prepared 3 isomers (o, m, p-bromophenyl)-bis(2,6-dimethylphenyl)boranes. Among the 3 isomers (o-, m- and p-BrTAB) synthesized, the ortho-one is the only one which shows dual phosphorescence, with a short lifetime of 0.8 ms and a long lifetime of 234 ms in the crystalline state at room temperature. Based on theoretical calculations and crystal structure analysis of o-BrTAB, the short lifetime component is ascribed to the T\(^M_1\) state of the monomer which emits the higher energy phosphorescence. The long-lived, lower energy phosphorescence emission is attributed to the T\(^A_1\) state of an aggregate, with multiple intermolecular interactions existing in crystalline o-BrTAB inhibiting nonradiative decay and stabilizing the triplet states efficiently.}, language = {en} } @article{WortmannSalehEngelsPeyerimhoff1994, author = {Wortmann-Saleh, D. and Engels, Bernd and Peyerimhoff, S. D.}, title = {Theoretical Study of the Reaction O(\(^3\)P) + C\(_2\)H\(_4\) and comparison with the \(^3\)CH\(_3\) + C\(_2\)H\(_4\) Reaction}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-59076}, year = {1994}, abstract = {The minimum energy path for the reaction O(\(^3\)P\(_g\)) + C\(_2\)H\(_4\)(\(^1\)A\(_g\)) has been calculated by optimizing all relevant geometrical parameters along the approach of oxygen to ethene. A barrier of 4.7 kcal/mol in the \(^3\)A"( ... 9a'\(^2\)- 10a'3a") potential energy surface and an energy difference of 14.4 kcal/mol between the product and the fragments is found at the multireference-configuration interaction level. The corresponding values at the lower-level treatment CASSCF are 9 kcal/mol for the barrier and 9 kcal/mol for the depth of the potential; this shows the importance of inclusion of electron correlation. The barrier for CH\(_2\) rotation for the lowestenergy structure (asymmetric OC\(_2\)H\(_4\)) is around 5 kcal/mol. The energy gap to the first excited state \(^3\)A'( ... 9a'l0a'3a'12) is found tobe 3.6 kcal/mol in MRD-CI calculations at the ground-state minimum. Comparison with \(^3\)CH\(_2\) + C\(_2\)H\(_4\) shows that in this system the lowest-energy surface is \(^3\)A', i.e., the state which is the excited state in 0 + C\(_2\)H\(_4\). This difference in energy ordering of \(^3\)A' and \(^3\)A" states results from the fact that the p\(_x\), p\(_y\), p\(_z\) degeneracy of oxygen orbitals is lifted in \(^3\)CH\(_2\)leading to b\(_1\), b\(_2\). and a\(_1\) MOs whereby the lowest b\(_2\) (a") remains doubly occupied; as a consequence, the reaction pattem between the oxygen and \(^3\)CH\(_2\) approach is different, which is also quite apparent in the calculated charge transfer.}, subject = {Organische Chemie}, language = {en} }