@article{AbdelhameedEltamanyHaletal.2020, author = {Abdelhameed, Reda F. A. and Eltamany, Enas E. and Hal, Dina M. and Ibrahim, Amany K. and AboulMagd, Asmaa M. and Al-Warhi, Tarfah and Youssif, Khayrya A. and Abd El-kader, Adel M. and Hassanean, Hashim A. and Fayez, Shaimaa and Bringmann, Gerhard and Ahmed, Safwat A. and Abdelmohsen, Usama Ramadan}, title = {New cytotoxic cerebrosides from the Red Sea cucumber Holothuria spinifera supported by in-silico studies}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {8}, issn = {1660-3397}, doi = {10.3390/md18080405}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-211089}, year = {2020}, abstract = {Bioactivity-guided fractionation of a methanolic extract of the Red Sea cucumber Holothuria spinifera and LC-HRESIMS-assisted dereplication resulted in the isolation of four compounds, three new cerebrosides, spiniferosides A (1), B (2), and C (3), and cholesterol sulfate (4). The chemical structures of the isolated compounds were established on the basis of their 1D NMR and HRMS spectral data. Metabolic profiling of the H. spinifera extract indicated the presence of diverse secondary metabolites, mostly hydroxy fatty acids, diterpenes, triterpenes, and cerebrosides. The isolated compounds were tested for their in vitro cytotoxicities against the breast adenocarcinoma MCF-7 cell line. Compounds 1, 2, 3, and 4 displayed promising cytotoxic activities against MCF-7 cells, with IC\(_{50}\) values of 13.83, 8.13, 8.27, and 35.56 µM, respectively, compared to that of the standard drug doxorubicin (IC\(_{50}\) 8.64 µM). Additionally, docking studies were performed for compounds 1, 2, 3, and 4 to elucidate their binding interactions with the active site of the SET protein, an inhibitor of protein phosphatase 2A (PP2A), which could explain their cytotoxic activity. This study highlights the important role of these metabolites in the defense mechanism of the sea cucumber against fouling organisms and the potential uses of these active molecules in the design of new anticancer agents.}, language = {en} } @article{AbdelhameedHabibEltahawyetal.2020, author = {Abdelhameed, Reda F. A. and Habib, Eman S. and Eltahawy, Nermeen A. and Hassanean, Hashim A. and Ibrahim, Amany K. and Mohammed, Anber F. and Fayez, Shaimaa and Hayallah, Alaa M. and Yamada, Koji and Behery, Fathy A. and Al-Sanea, Mohammad M. and Alzarea, Sami I. and Bringmann, Gerhard and Ahmed, Safwat A. and Abdelmohsen, Usama Ramadan}, title = {New cytotoxic natural products from the Red Sea sponge Stylissa carteri}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {5}, issn = {1660-3397}, doi = {10.3390/md18050241}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-205795}, year = {2020}, abstract = {Bioactivity-guided isolation supported by LC-HRESIMS metabolic profiling led to the isolation of two new compounds, a ceramide, stylissamide A (1), and a cerebroside, stylissoside A (2), from the methanol extract of the Red Sea sponge Stylissa carteri. Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The bioactive extract's metabolomic profiling showed the existence of various secondary metabolites, mainly oleanane-type saponins, phenolic diterpenes, and lupane triterpenes. The in vitro cytotoxic activity of the isolated compounds was tested against two human cancer cell lines, MCF-7 and HepG2. Both compounds, 1 and 2, displayed strong cytotoxicity against the MCF-7 cell line, with IC\(_{50}\) values at 21.1 ± 0.17 µM and 27.5 ± 0.18 µM, respectively. They likewise showed a promising activity against HepG2 with IC\(_{50}\) at 36.8 ± 0.16 µM for 1 and IC\(_{50}\) 30.5 ± 0.23 µM for 2 compared to the standard drug cisplatin. Molecular docking experiments showed that 1 and 2 displayed high affinity to the SET protein and to inhibitor 2 of protein phosphatase 2A (I2PP2A), which could be a possible mechanism for their cytotoxic activity. This paper spreads light on the role of these metabolites in holding fouling organisms away from the outer surface of the sponge, and the potential use of these defensive molecules in the production of novel anticancer agents.}, language = {en} } @article{AbdelhameedHabibGodaetal.2020, author = {Abdelhameed, Reda F. A. and Habib, Eman S. and Goda, Marwa S. and Fahim, John Refaat and Hassanean, Hashem A. and Eltamany, Enas E. and Ibrahim, Amany K. and AboulMagd, Asmaa M. and Fayez, Shaimaa and Abd El-kader, Adel M. and Al-Warhi, Tarfah and Bringmann, Gerhard and Ahmed, Safwat A. and Abdelmohsen, Usama Ramadan}, title = {Thalassosterol, a New Cytotoxic Aromatase Inhibitor Ergosterol Derivative from the Red Sea Seagrass Thalassodendron ciliatum}, series = {Marine Drugs}, volume = {18}, journal = {Marine Drugs}, number = {7}, doi = {10.3390/md18070354}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236085}, year = {2020}, abstract = {Thalassodendron ciliatum (Forssk.) Den Hartog is a seagrass belonging to the plant family Cymodoceaceae with ubiquitous phytoconstituents and important pharmacological potential, including antioxidant, antiviral, and cytotoxic activities. In this work, a new ergosterol derivative named thalassosterol (1) was isolated from the methanolic extract of T. ciliatum growing in the Red Sea, along with two known first-reported sterols, namely ergosterol (2) and stigmasterol (3), using different chromatographic techniques. The structure of the new compound was established based on 1D and 2D NMR spectroscopy and high-resolution mass spectrometry (HR-MS) and by comparison with the literature data. The new ergosterol derivative showed significant in vitro antiproliferative potential against the human cervical cancer cell line (HeLa) and human breast cancer (MCF-7) cell lines, with IC\(_{50}\) values of 8.12 and 14.24 µM, respectively. In addition, docking studies on the new sterol 1 explained the possible binding interactions with an aromatase enzyme; this inhibition is beneficial in both cervical and breast cancer therapy. A metabolic analysis of the crude extract of T. ciliatum using liquid chromatography combined with high-resolution electrospray ionization mass spectrometry (LC-ESI-HR-MS) revealed the presence of an array of phenolic compounds, sterols and ceramides, as well as di- and triglycerides.}, language = {en} } @article{AltmannMutWolfetal.2021, author = {Altmann, Stephan and Mut, J{\"u}rgen and Wolf, Natalia and Meißner-Weigl, Jutta and Rudert, Maximilian and Jakob, Franz and Gutmann, Marcus and L{\"u}hmann, Tessa and Seibel, J{\"u}rgen and Ebert, Regina}, title = {Metabolic glycoengineering in hMSC-TERT as a model for skeletal precursors by using modified azide/alkyne monosaccharides}, series = {International Journal of Molecular Sciences}, volume = {22}, journal = {International Journal of Molecular Sciences}, number = {6}, issn = {1422-0067}, doi = {10.3390/ijms22062820}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259247}, year = {2021}, abstract = {Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac\(_4\)ManNAz) and N-alkyneacetylmannosamine (Ac\(_4\)ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac\(_4\)ManNAz was detectable for up to six days while Ac\(_4\)ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.}, language = {en} } @article{BastChristlHuisgenetal.1972, author = {Bast, K. and Christl, Manfred and Huisgen, R. and Mack, W.}, title = {Additionen der Nitriloxide an CN-Mehrfachbindungen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57879}, year = {1972}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{BastChristlHuisgenetal.1973, author = {Bast, K. and Christl, Manfred and Huisgen, R. and Mack, W.}, title = {Relative Dipolarophilen-Aktivit{\"a}ten bei Cycloadditionen des Benzonitriloxids}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57935}, year = {1973}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{BastChristlHuisgenetal.1973, author = {Bast, K. and Christl, Manfred and Huisgen, R. and Mack, W. and Sustmann, R.}, title = {Additionen des Benzonitriloxids an olefinische und acetylenische Dipolarophile}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57905}, year = {1973}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{BastChristlHuisgenetal.1973, author = {Bast, K. and Christl, Manfred and Huisgen, R. and Sustmann, R.}, title = {Zur Anlagerung des Benzonitriloxids an α,β-unges{\"a}ttigte Carbons{\"a}ureester}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57912}, year = {1973}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{BecamWalterBurgertetal.2017, author = {Becam, J{\´e}r{\^o}me and Walter, Tim and Burgert, Anne and Schlegel, Jan and Sauer, Markus and Seibel, J{\"u}rgen and Schubert-Unkmeir, Alexandra}, title = {Antibacterial activity of ceramide and ceramide analogs against pathogenic Neisseria}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, doi = {10.1038/s41598-017-18071-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159367}, pages = {17627}, year = {2017}, abstract = {Certain fatty acids and sphingoid bases found at mucosal surfaces are known to have antibacterial activity and are thought to play a more direct role in innate immunity against bacterial infections. Herein, we analysed the antibacterial activity of sphingolipids, including the sphingoid base sphingosine as well as short-chain C\(_{6}\) and long-chain C\(_{16}\)-ceramides and azido-functionalized ceramide analogs against pathogenic Neisseriae. Determination of the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) demonstrated that short-chain ceramides and a ω-azido-functionalized C\(_{6}\)-ceramide were active against Neisseria meningitidis and N. gonorrhoeae, whereas they were inactive against Escherichia coli and Staphylococcus aureus. Kinetic assays showed that killing of N. meningitidis occurred within 2 h with ω-azido-C\(_{6}\)-ceramide at 1 X the MIC. Of note, at a bactericidal concentration, ω-azido-C\(_{6}\)-ceramide had no significant toxic effect on host cells. Moreover, lipid uptake and localization was studied by flow cytometry and confocal laser scanning microscopy (CLSM) and revealed a rapid uptake by bacteria within 5 min. CLSM and super-resolution fluorescence imaging by direct stochastic optical reconstruction microscopy demonstrated homogeneous distribution of ceramide analogs in the bacterial membrane. Taken together, these data demonstrate the potent bactericidal activity of sphingosine and synthetic short-chain ceramide analogs against pathogenic Neisseriae.}, language = {en} } @article{BentleyChristlKemmeretal.1994, author = {Bentley, T. W. and Christl, Manfred and Kemmer, R. and Llewellyn, G. and Oakley, J. E.}, title = {Kinetic and Spectroscopic Characterisation of Highly Reactive Methanesulfonates. Leaving Group Effects for Solvolyses and Comments on Geminal Electronic Effects Influencing S\(_N\)1 Reactivity}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58748}, year = {1994}, abstract = {Highly reactive methanesulfonates (mesylates, ROMs) have been prepared from 1-phenylethanol. cyclohex-2-en-1-ol, diphenylmethanol and p-methoxybenzyl alcohol by treatment with methanesulfonyl chloride and triethylamine in dichloro- or trichloro-methane at - 20 to 0 °C. The mesylates. characterised in solution by \(^1\)H and \(^{13}\)C NMR at -20 °C, were obtained in satisfactory purity (ca. 95\%) in cold solutions but they decomposed by reaction with chloride, triethylamine or the parent alcohol. Rate constants for solvolyses in aqueous acetone and aqueous ethanol have been determined by a fast response conductimetric method. Product selectivities for solvolyses of pmethoxybenzyl mesylate in aqueous ethanol and methanol at 0 °C have been determined by HPLC. From additional new or Iiterature kinetic data for solvolyses of corresponding bromides. chlorides and p-nitrobenzoates (OPNB). Br/CI. OMs/Br and OMs/OPNB rate ratios were calculated; the results are consistent with electronic effects stabilising the carbocationic transition states and increasing OMs/Br rate ratios for these SN 1 solvolyses; none of the evidence supports a geminal electronic effect on Br/CI rate ratios (e.g. caused by stabilisation of the initial state in pmethoxybenzyl chloride). Steric effects on ester /halide rate ratios for solvolyses of tertiary substrates are confirmed. Relative rates over a 10\(^{16}\) range for ester and halide leaving groups are evaluated for solvolyses of 1-phenylethyl substrates in 80\% ethanol-water. updating previous work by Noyce et al. (1972).}, subject = {Organische Chemie}, language = {en} } @article{BentleyChristlNorman1991, author = {Bentley, T. W. and Christl, Manfred and Norman, S. J.}, title = {Methanesulfonate/p-Nitrobenzoate and p-Toluenesulfonate/p-Nitrobenzoate Rate Ratios. Solvolyses of 1-Adamantyl and Benzhydryl Substrates}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58599}, year = {1991}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{BentleyNormanGerstneretal.1993, author = {Bentley, T. W. and Norman, S. J. and Gerstner, E. and Kemmer, R. and Christl, Manfred}, title = {Solvolysis of Tricyclo[3.1.0.0\(^{2,6}\)]hex-3-yl and Bicyclo[2.1.1]hex-2-yl Sulfonates}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58689}, year = {1993}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{BialasZitzlerKunkelKirchneretal.2016, author = {Bialas, David and Zitzler-Kunkel, Andr{\´e} and Kirchner, Eva and Schmidt, David and W{\"u}rthner, Frank}, title = {Structural and quantum chemical analysis of exciton coupling in homo- and heteroaggregate stacks of merocyanines}, series = {Nature Communications}, volume = {7}, journal = {Nature Communications}, doi = {10.1038/ncomms12949}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170200}, year = {2016}, abstract = {Exciton coupling is of fundamental importance and determines functional properties of organic dyes in (opto-)electronic and photovoltaic devices. Here we show that strong exciton coupling is not limited to the situation of equal chromophores as often assumed. Quadruple dye stacks were obtained from two bis(merocyanine) dyes with same or different chromophores, respectively, which dimerize in less-polar solvents resulting in the respective homo- and heteroaggregates. The structures of the quadruple dye stacks were assigned by NMR techniques and unambiguously confirmed by single-crystal X-ray analysis. The heteroaggregate stack formed from the bis(merocyanine) bearing two different chromophores exhibits remarkably different ultraviolet/vis absorption bands compared with those of the homoaggregate of the bis(merocyanine) comprising two identical chromophores. Quantum chemical analysis based on an extension of Kasha's exciton theory appropriately describes the absorption properties of both types of stacks revealing strong exciton coupling also between different chromophores within the heteroaggregate.}, language = {en} } @article{BinasBessiSchwalbe2020, author = {Binas, Oliver and Bessi, Irene and Schwalbe, Harald}, title = {Structure Validation of G-Rich RNAs in Noncoding Regions of the Human Genome}, series = {ChemBioChem}, volume = {21}, journal = {ChemBioChem}, number = {11}, doi = {10.1002/cbic.201900696}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214892}, pages = {1656 -- 1663}, year = {2020}, abstract = {We present the rapid biophysical characterization of six previously reported putative G-quadruplex-forming RNAs from the 5′-untranslated region (5′-UTR) of silvestrol-sensitive transcripts for investigation of their secondary structures. By NMR and CD spectroscopic analysis, we found that only a single sequence—[AGG]\(_{2}\)[CGG]\(_{2}\)C—folds into a single well-defined G-quadruplex structure. Sequences with longer poly-G strands form unspecific aggregates, whereas CGG-repeat-containing sequences exhibit a temperature-dependent equilibrium between a hairpin and a G-quadruplex structure. The applied experimental strategy is fast and provides robust readout for G-quadruplex-forming capacities of RNA oligomers.}, language = {en} } @article{BoldStolteShoyamaetal.2022, author = {Bold, Kevin and Stolte, Matthias and Shoyama, Kazutaka and Holzapfel, Marco and Schmiedel, Alexander and Lambert, Christoph and W{\"u}rthner, Frank}, title = {Macrocyclic donor-acceptor dyads composed of a perylene bisimide dye surrounded by oligothiophene bridges}, series = {Angewandte Chemie Internationale Edition}, volume = {61}, journal = {Angewandte Chemie Internationale Edition}, number = {1}, doi = {10.1002/anie.202113598}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256569}, year = {2022}, abstract = {Two macrocyclic architectures comprising oligothiophene strands that connect the imide positions of a perylene bisimide (PBI) dye have been synthesized via a platinum-mediated cross-coupling strategy. The crystal structure of the double bridged PBI reveals all syn-arranged thiophene units that completely enclose the planar PBI chromophore via a 12-membered macrocycle. The target structures were characterized by steady-state UV/Vis absorption, fluorescence and transient absorption spectroscopy, as well as cyclic and differential pulse voltammetry. Both donor-acceptor dyads show ultrafast F{\"o}rster Resonance Energy Transfer and photoinduced electron transfer, thereby leading to extremely low fluorescence quantum yields even in the lowest polarity cyclohexane solvent.}, language = {en} } @article{BoldStolteShoyamaetal.2022, author = {Bold, Kevin and Stolte, Matthias and Shoyama, Kazutaka and Krause, Ana-Maria and Schmiedel, Alexander and Holzapfel, Marco and Lambert, Christoph and W{\"u}rthner, Frank}, title = {Macrocyclic Donor-Acceptor Dyads Composed of Oligothiophene Half-Cycles and Perylene Bisimides}, series = {Chemistry - A European Journal}, volume = {28}, journal = {Chemistry - A European Journal}, number = {30}, doi = {10.1002/chem.202200355}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-276435}, year = {2022}, abstract = {A series of donor-acceptor (D-A) macrocyclic dyads consisting of an electron-poor perylene bisimide (PBI) π-scaffold bridged with electron-rich α-oligothiophenes bearing four, five, six and seven thiophene units between the two phenyl-imide substituents has been synthesized and characterized by steady-state UV/Vis absorption and fluorescence spectroscopy, cyclic and differential pulse voltammetry as well as transient absorption spectroscopy. Tying the oligothiophene strands in a conformationally fixed macrocyclic arrangement leads to a more rigid π-scaffold with vibronic fine structure in the respective absorption spectra. Electrochemical analysis disclosed charged state properties in solution which are strongly dependent on the degree of rigidification within the individual macrocycle. Investigation of the excited state dynamics revealed an oligothiophene bridge size-dependent fast charge transfer process for the macrocyclic dyads upon PBI subunit excitation.}, language = {en} } @article{BrennerGeigerSchlegeletal.2023, author = {Brenner, Daniela and Geiger, Nina and Schlegel, Jan and Diesendorf, Viktoria and Kersting, Louise and Fink, Julian and Stelz, Linda and Schneider-Schaulies, Sibylle and Sauer, Markus and Bodem, Jochen and Seibel, J{\"u}rgen}, title = {Azido-ceramides, a tool to analyse SARS-CoV-2 replication and inhibition — SARS-CoV-2 is inhibited by ceramides}, series = {International Journal of Molecular Sciences}, volume = {24}, journal = {International Journal of Molecular Sciences}, number = {8}, issn = {1422-0067}, doi = {10.3390/ijms24087281}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313581}, year = {2023}, abstract = {Recently, we have shown that C6-ceramides efficiently suppress viral replication by trapping the virus in lysosomes. Here, we use antiviral assays to evaluate a synthetic ceramide derivative α-NH2-ω-N3-C6-ceramide (AKS461) and to confirm the biological activity of C6-ceramides inhibiting SARS-CoV-2. Click-labeling with a fluorophore demonstrated that AKS461 accumulates in lysosomes. Previously, it has been shown that suppression of SARS-CoV-2 replication can be cell-type specific. Thus, AKS461 inhibited SARS-CoV-2 replication in Huh-7, Vero, and Calu-3 cells up to 2.5 orders of magnitude. The results were confirmed by CoronaFISH, indicating that AKS461 acts comparable to the unmodified C6-ceramide. Thus, AKS461 serves as a tool to study ceramide-associated cellular and viral pathways, such as SARS-CoV-2 infections, and it helped to identify lysosomes as the central organelle of C6-ceramides to inhibit viral replication.}, language = {en} } @article{BrixnerKochKullmannetal.2013, author = {Brixner, Tobias and Koch, Federico and Kullmann, Martin and Selig, Ulrike and Nuernberger, Patrick and G{\"o}tz, Daniel C. G. and Bringmann, Gerhard}, title = {Coherent two-dimensional electronic spectroscopy in the Soret band of a chiral porphyrin dimer}, series = {New Journal of Physics}, journal = {New Journal of Physics}, doi = {10.1088/1367-2630/15/2/025006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96139}, year = {2013}, abstract = {Using coherent two-dimensional (2D) electronic spectroscopy in fully noncollinear geometry, we observe the excitonic coupling of β,β'-linked bis[tetraphenylporphyrinato-zinc(II)] on an ultrafast timescale in the excited state. The results for two states in the Soret band originating from an excitonic splitting are explained by population transfer with approximately 100 fs from the energetically higher to the lower excitonic state. This interpretation is consistent with exemplary calculations of 2D spectra for a model four-level system with coupling.}, language = {en} } @article{BrustNaglerShoyamaetal.2023, author = {Brust, Felix and Nagler, Oliver and Shoyama, Kazutaka and Stolte, Matthias and W{\"u}rthner, Frank}, title = {Organic Light-Emitting Diodes Based on Silandiol-Bay-Bridged Perylene Bisimides}, series = {Advanced Optical Materials}, volume = {11}, journal = {Advanced Optical Materials}, number = {5}, doi = {10.1002/adom.202202676}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312599}, year = {2023}, abstract = {Perylene bisimides (PBIs) are among the best fluorophores but have to be enwrapped for optoelectronic applications by large and heavy substituents to prevent their ππ-stacking, which is known to accelerate non-radiative decay processes in the solid state. Here, light-weight di-tert-butylsilyl groups are introduced to bridge 1,12-dihydroxy and 1,6,7,12-tetrahydroxy PBIs to afford sublimable dyes for vacuum-processed optoelectronic devices. For both new compounds, this substitution provides a twisted and shielded perylene π-core whose, via OSiObridges, rigid structure affords well-resolved absorption and emission spectra with strong fluorescence in solution, as well as in the solid state. The usefulness of these dyes for vacuum-processed optoelectronic devices is demonstrated in organic light-emitting diodes (OLEDs) that show monomer-like emission spectra and high maximum external quantum efficiency (EQEmax) values of up to 3.1\% for the doubly silicon-bridged PBI.}, language = {en} } @article{BruennertSeupelGoyaletal.2023, author = {Br{\"u}nnert, Daniela and Seupel, Raina and Goyal, Pankaj and Bach, Matthias and Schraud, Heike and Kirner, Stefanie and K{\"o}ster, Eva and Feineis, Doris and Bargou, Ralf C. and Schlosser, Andreas and Bringmann, Gerhard and Chatterjee, Manik}, title = {Ancistrocladinium A induces apoptosis in proteasome inhibitor-resistant multiple myeloma cells: a promising therapeutic agent candidate}, series = {Pharmaceuticals}, volume = {16}, journal = {Pharmaceuticals}, number = {8}, issn = {1424-8247}, doi = {10.3390/ph16081181}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-362887}, year = {2023}, abstract = {The N,C-coupled naphthylisoquinoline alkaloid ancistrocladinium A belongs to a novel class of natural products with potent antiprotozoal activity. Its effects on tumor cells, however, have not yet been explored. We demonstrate the antitumor activity of ancistrocladinium A in multiple myeloma (MM), a yet incurable blood cancer that represents a model disease for adaptation to proteotoxic stress. Viability assays showed a potent apoptosis-inducing effect of ancistrocladinium A in MM cell lines, including those with proteasome inhibitor (PI) resistance, and in primary MM cells, but not in non-malignant blood cells. Concomitant treatment with the PI carfilzomib or the histone deacetylase inhibitor panobinostat strongly enhanced the ancistrocladinium A-induced apoptosis. Mass spectrometry with biotinylated ancistrocladinium A revealed significant enrichment of RNA-splicing-associated proteins. Affected RNA-splicing-associated pathways included genes involved in proteotoxic stress response, such as PSMB5-associated genes and the heat shock proteins HSP90 and HSP70. Furthermore, we found strong induction of ATF4 and the ATM/H2AX pathway, both of which are critically involved in the integrated cellular response following proteotoxic and oxidative stress. Taken together, our data indicate that ancistrocladinium A targets cellular stress regulation in MM and improves the therapeutic response to PIs or overcomes PI resistance, and thus may represent a promising potential therapeutic agent.}, language = {en} } @article{BruentrupChristl1973, author = {Br{\"u}ntrup, Gisela and Christl, Manfred}, title = {Darstellung und Thermolyse der Hexamethyldewarbenzol-Cycloaddukte aromatischer Nitriloxide und des Diphenylnitrilimins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30257}, year = {1973}, abstract = {No abstract available}, language = {en} } @article{BaeumerKarthaAllampallyetal.2019, author = {B{\"a}umer, Nils and Kartha, Kalathil K. and Allampally, Naveen Kumar and Yagai, Shiki and Albuquerque, Rodrigo Q. and Fern{\´a}ndez, Gustavo}, title = {Kontrolle {\"u}ber Selbstassemblierung durch Ausnutzung von Koordinationsisomerie}, series = {Angewandte Chemie}, volume = {131}, journal = {Angewandte Chemie}, number = {44}, doi = {10.1002/ange.201908002}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212176}, pages = {15772 -- 15776}, year = {2019}, abstract = {Hierin wird die inh{\"a}rente geometrische Isomerie eines PtII Komplexes als neues Werkzeug zur Kontrolle von supramolekularen Assemblierungsprozessen ausgenutzt. Bestrahlung mit UV-Licht sowie die sorgf{\"a}ltige Auswahl des verwendeten L{\"o}sungsmittels, der Temperatur und Konzentration f{\"u}hren zu einer regelbaren Koordinationsisomerie. Dies erm{\"o}glicht ein vollst{\"a}ndig reversibles Schalten zwischen zwei definierten aggregierten Spezies (1D Fasern ↔ 2D Lamellen) mit unterschiedlichem photoresponsivem Verhalten. Unsere Erkenntnisse erweitern nicht nur die Reichweite von Koordinationsisomerie, sondern er{\"o}ffnen auch aufregende M{\"o}glichkeiten zur Entwicklung neuartiger stimuliresponsiver Materialien.}, language = {de} } @article{BuendgenEngelsPeyerimhoff1991, author = {B{\"u}ndgen, P. and Engels, Bernd and Peyerimhoff, S.D.}, title = {An MRD-CI study of low-lying electronic states in CaF}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58880}, year = {1991}, abstract = {Dipole moments and various spectroscopic constants of some low-lying electronic states of the CaF molecule have been calculated using the multireference single· and double-excitation configuration-interaction (MRD-CI) method. The electronic structure of the highly ionic molecule in various excited states can be explained in tenns of different polarisations of the mainly Cacentered valence electron in the field of the F\(^-\) anion. Plots of natural orbitals occupied by the valence electron in the different states give a qualitative picture of the charge distribution and provide a visualisation of the different polarisations of the valence electron in the various states. Comparisons with the electrostatic polarisation model ofT{\"o}rring, Ernstand K{\"a}ndler (TEK model) are made. The unknown A' \(^2 \Delta\) state is predicted to lie about 21200 cm\(^{-1}\) above the ground state.}, subject = {Organische Chemie}, language = {en} } @article{CecilRikanovicOhlsenetal.2011, author = {Cecil, Alexander and Rikanovic, Carina and Ohlsen, Knut and Liang, Chunguang and Bernhardt, Jorg and Oelschlaeger, Tobias A. and Gulder, Tanja and Bringmann, Gerd and Holzgrabe, Ulrike and Unger, Matthias and Dandekar, Thomas}, title = {Modeling antibiotic and cytotoxic effects of the dimeric isoquinoline IQ-143 on metabolism and its regulation in Staphylococcus aureus, Staphylococcus epidermidis and human cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68802}, year = {2011}, abstract = {Background: Xenobiotics represent an environmental stress and as such are a source for antibiotics, including the isoquinoline (IQ) compound IQ-143. Here, we demonstrate the utility of complementary analysis of both host and pathogen datasets in assessing bacterial adaptation to IQ-143, a synthetic analog of the novel type N,C-coupled naphthyl-isoquinoline alkaloid ancisheynine. Results: Metabolite measurements, gene expression data and functional assays were combined with metabolic modeling to assess the effects of IQ-143 on Staphylococcus aureus, Staphylococcus epidermidis and human cell lines, as a potential paradigm for novel antibiotics. Genome annotation and PCR validation identified novel enzymes in the primary metabolism of staphylococci. Gene expression response analysis and metabolic modeling demonstrated the adaptation of enzymes to IQ-143, including those not affected by significant gene expression changes. At lower concentrations, IQ-143 was bacteriostatic, and at higher concentrations bactericidal, while the analysis suggested that the mode of action was a direct interference in nucleotide and energy metabolism. Experiments in human cell lines supported the conclusions from pathway modeling and found that IQ-143 had low cytotoxicity. Conclusions: The data suggest that IQ-143 is a promising lead compound for antibiotic therapy against staphylococci. The combination of gene expression and metabolite analyses with in silico modeling of metabolite pathways allowed us to study metabolic adaptations in detail and can be used for the evaluation of metabolic effects of other xenobiotics.}, subject = {Staphylococcus aureus}, language = {en} } @article{CeymanRosspeintnerSchrecketal.2016, author = {Ceyman, Harald and Rosspeintner, Arnulf and Schreck, Maximilian H. and M{\"u}tzel, Carina and Stoy, Andreas and Vauthey, Eric and Lambert, Christoph}, title = {Cooperative enhancement versus additivity of two-photon-absorption cross sections in linear and branched squaraine superchromophores}, series = {Physical Chemistry Chemical Physics}, volume = {18}, journal = {Physical Chemistry Chemical Physics}, number = {24}, doi = {10.1039/c6cp02312f}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188299}, pages = {16404-16413}, year = {2016}, abstract = {The linear and nonlinear optical properties of a series of oligomeric squaraine dyes were investigated by one-photon absorption spectroscopy (1PA) and two-photon absorption (2PA) induced fluorescence spectroscopy. The superchromophores are based on two indolenine squaraine dyes with transoid (SQA) and cisoid configuration (SQB). Using these monomers, linear dimers and trimers as well as star-shaped trimers and hexamers with benzene or triphenylamine cores were synthesised and investigated. The red-shifted and intensified 1PA spectra of all superchromophores could well be explained by exciton coupling theory. In the linear chromophore arrangements we also found superradiance of fluorescence but not in the branched systems. Furthermore, the 2PA showed enhanced cross sections for the linear oligomers but only additivity for the branched systems. This emphasizes that the enhancement of the 2PA cross section in the linear arrangements is probably caused by orbital interactions of higher excited configurations.}, language = {en} } @article{Christl1975, author = {Christl, Manfred}, title = {\(^{13}\)-NMR-Spektren von Bicyclo[n.1.0]kohlenwasserstoffen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57977}, year = {1975}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{Christl1975, author = {Christl, Manfred}, title = {Carbon-13 Chemical Shifts and 13C-15N Coupling Constants of 3,4-Dihydroisoquinoline-15N, its 15N-Oxide and their Conjugate Acids}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30071}, year = {1975}, abstract = {No abstract available}, language = {en} } @article{Christl1981, author = {Christl, Manfred}, title = {Benzvalen - Eigenschaften und Synthesepotential}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30041}, year = {1981}, abstract = {No abstract available}, language = {de} } @article{Christl1973, author = {Christl, Manfred}, title = {Cycloaddition an Benzvalen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30217}, year = {1973}, abstract = {No abstract available}, language = {de} } @article{ChristlBraun1989, author = {Christl, Manfred and Braun, Martin}, title = {Generation and interception of 1-OXA-2,3-Cyclohexadiene and 1,2,4-Cyclohexatriene}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-56566}, year = {1989}, abstract = {The cycloadducts 6 and 7 of tricyc1o[4.1.0.0 2 ,7)hepta- 3,4-diene (~) with styrene and 1,3-butadiene rearrange to unusual products on thermolysis, namely the cycloheptatriene derivatives ~ and 10. 1-0xa-3,4-cyclohexadiene (20) is generated smoothly from 6,6-dichloro-3-oxabicyclo[3.1.0]hexane (22) and n-butyllithium. 1-0xa-2,3-cyclohexadiene (11) is formed from 6-exo-bromo-6-endo-fluoro-2-oxabicyclo[ 3.1.0]hexane (30) and methyllithium. In the presence of activated olefins, this reaction provides an efficient route to 28 and 33 - 38, the trapping products of 21. Interestingly, [2+2]-cycloadditions do not take place at the same double bond of 21 as [4+2]-cycloadditions. The reactions of 1,3-cyclopentadiene and indene with bromofluorocarbene afford 6-exo-bromo-6-endo-fluorobicyclo[3.1.0]hex-2-ene (50) and its benzo derivative ~, respectively. On treatment of these compounds with methyl lithium in the presence of styrene, the interception products 53 and 47 of 1,2,4-cyc10- hexatriene (44) and its benzo derivative 43, respectively, are formed in good yields.}, subject = {Chemie}, language = {en} } @article{ChristlBraun1989, author = {Christl, Manfred and Braun, Martin}, title = {Freisetzung und Abfangreaktionen von 1-Oxa-2,3-cyclohexadien}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58517}, year = {1989}, abstract = {Umsetzung von 6,6-Dichlor-2-oxabicyclo[3.1.0)hexan (4a) in Styrol mit n-Butyllithium lieferte neben Polystyrol und t-Chlor-1- pbenylhexan (6) in geringer Ausbeute die Tet~hydrocyclobutapyrane 5, die Abfangprodukte des aus 4a generierten t-Oxa-2,3- cyclobexadiens (3). Das unbest{\"a}ndige 6,6-Dibrom-2-oxabicyclo( J.l.O]hexan (4b) wurde bei -60°C erzeugt un~ bei -30°C mit Methyllithium in Gegenwart von Styrol umgesetzt, woraus die Produkte 5 mit 24\% Ausbeute hervorgingen. Als bei 20°C best{\"a}ndige Quelle f{\"u}r 3 erwies sich exo-6-Brom-e~o-6-fluor-2-oxabicyclo[ J.t.O]bexan (9), das aus 2,3-Dihydrofuran und Bromßuorcarben mit 25\% Ausbeute bereitet wurde. Behandlung von 9 in Styrol, 13C-NMR-Spektren von Tetracyclo[4.1.0.02,4.03,5]heptanen, Tetracyclo[5.1.0.02,4.03,5]octanen und Tricyclo[4.1.0.02,7]hept-3-enen. Ungew{\"o}hnliche beta- und gamma-Substituenteneffekte}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30087}, year = {1978}, abstract = {No abstract available}, language = {de} } @article{ChristlFreitag1976, author = {Christl, Manfred and Freitag, G.}, title = {Das Tricyclo[4.1.0.0\(^{2,7}\)]heptenyl-Kation, ein neues Isomer des Tropylium-Ions}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57985}, year = {1976}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlFreitagBruentrup1978, author = {Christl, Manfred and Freitag, G. and Br{\"u}ntrup, G.}, title = {Der Aufbau des Tetracyclo[4.1.0.0\(^{2,4}\).0\(^{3,5}\)]heptan-Systems durch Addition halogensubstituierter Carbene an Benzvalen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58019}, year = {1978}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlFreitagBruentrup1978, author = {Christl, Manfred and Freitag, G. and Br{\"u}ntrup, G.}, title = {Tricyclo[4.1.0.0\(^{2,7}\)]hept-3-ene durch Umlagerung von 7-endo-Brom- und 7-endo-Chlortetracyclo[4.1.0.0\(^{2,4}\).0\(^{3,5}\)]heptanen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58029}, year = {1978}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlFreund1985, author = {Christl, Manfred and Freund, S.}, title = {Substituierte Benzobenzvalene und Diazabenzobenzvalene - Synthesen aus Diels-Alder-Addukten des Benzvalens und NMR-Spektroskopie}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58183}, year = {1985}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlFreundHennebergeretal.1988, author = {Christl, Manfred and Freund, S. and Henneberger, H. and Kraft, A. and Hauck, J. and Irngartinger, H.}, title = {Several Polycyclic Valence Isomers of Dimethyl [14]Annulene-1,8-dicarboxylate. Reactivity of a "Nonconjugated" Bis(bicyclo[1.1.0]butane)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58413}, year = {1988}, abstract = {Diels-Alder reaction of dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate (5) with benzvalene (4), norbornene, and norbornadiene afforded the azo compounds 7 and 8. Theseare derivatives of 2,3-diazabicyclo[2.2.2]oct-2-ene as is azo compound 3, which had been obtained previously from 5 and 2 equiv of benzvalene (4). The photochemical extrusion of nitrogen from 3, 7, and 8 has been studied. Whereas 7 and 8 on direct irradiation in benzene gave rise exclusively to the bicyclo[2.2.0]hexane derivatives 9 and 10, respectively, from 3 in addition to the bicyclo[2.2.0]hexane 11, the diolefin 1l was formed. Diolefin 12 has cisdouble bonds in the nine-membered ring and is fixed in a boat conformation in a manner so that the two bicyclobutane systems approach each other very closely. This geometry suggests the unusual ring opening of the intermediate 1,4-cyclohexanediyl diradical from a boat conformation, which arises by inversion of the primarily generated boat conformation. Sensitized photolysis of 3 as weilasthat of ll produced the saturated isomer 13 of 11 and 12. The proximity of the bicyclobutane systems in 1l causes unprecedented reactions leading to cage compounds. When ll was heated at 90 °C, a rearrangement to the pentacyclic product 10 took place. Utilization of tetradeuteriated substrate ll-d4 supported a pathway with two diradical intermediates. Behaving in a convcntional manncr, bicyclobutane 9 and bis(bicyclobutane) 11 took up 1 and 2 equiv of thiophenol most probably in a radical-chain addition to give the thioethers 28 and 19, respectively. In contrast, bis(bicyclobutane) ll was converted by 1 equiv of thiophenol into cagc compound 30 in a process involving both the strained a systems. Heating at 80 °C subjected 30 to a reversible Copc rearrangement, resulting in a 6:1 mixture of 31 and 30. When it was treated with bromine, 11 was transformed to cage compound 38. This addition is believed to proceed via a cationic intermediate. The structure of cage compound 10 was established by a singlc-crystal X-ray analysis of dialcohol 11 prepared from 20 and methyllithium.}, subject = {Organische Chemie}, language = {en} } @article{ChristlGerstnerKemmeretal.1994, author = {Christl, Manfred and Gerstner, E. and Kemmer, R. and Llewellyn, G. and Bentley, T. W.}, title = {Elektrophile Additionen an das Bicyclo[1.1.0]butan-System von 1-Phenyl- und 1-(4-Anisyl)tricyclo[4.1.0.0\(^{2,7}\)]heptan: S{\"a}ure-katalysierte Reaktionen mit Wasser und Methanol, Anlagerung von Essigs{\"a}ure und Oxymercurierung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58696}, year = {1994}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHegmannReuchleinetal.1987, author = {Christl, Manfred and Hegmann, J. and Reuchlein, H. and Peters, K. and Peters, E.-M. and Schnering, H. G. von}, title = {{\"U}berbr{\"u}ckte neungliedrige α,β-unges{\"a}ttigte Enollactone - Synthese aus 5-Phenyl-1,3,4-oxadiazin-6-on-2-carbons{\"a}ure-methylester und Konfigurationsanalyse}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58395}, year = {1987}, abstract = {The γ-oxoketenes, which are formed from oxadiazinone Ja and strained cyclopentene der1vat1ves, are shown to undergo a pericyclic ring enlargement to give the title compounds 2a, 2b, and 5. In the case of 5, two configurations, one having a cis and the other a trans Iactone functionality, are in equilibrium.}, subject = {Organische Chemie}, language = {de} } @article{ChristlHeinemannKristof1975, author = {Christl, Manfred and Heinemann, U. and Kristof, W.}, title = {Thermal Rearrangement of Some Endo-Endo'-Bridged Bicyclo[1.1.0]butanes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57967}, year = {1975}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlHennebergerFreund1988, author = {Christl, Manfred and Henneberger, H. and Freund, S.}, title = {Halbk{\"a}figverbindungen aus Polycyclen mit einem Bicyclo[1.1.0]butan-System und dazu benachbarter Azobr{\"u}cke durch Radikalreaktionen mit Thiophenol und Bromtrichlormethan}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58440}, year = {1988}, abstract = {Aus Benzvalen (J) und 3,6-Bis(2-pyridyl)-l,2,4,5-tetrazin wurde das Dihydropyridazin 2c erhalten, das ebenso wie die bekannten Dihydropyridazine 2a, b mit Cyclopropen in die entsprechende Azoverbindung 3 {\"u}berging. Addition von Thiophenol an 3a, c und 5 lieferte unter Beteiligung des Bicyclobutan-Systems und der Azofunktion die Halbk{\"a}figverbindungen 4a, c bzw. 6. Aus der Umsetzung von 7, in dem die Azobr{\"u}cke durch zwei BicycJobutan- Systeme flankiert ist, mit Thiophenol sowie Bromtrichlormethan gingen die Halbk{\"a}figverbindungen 8 bzw. 9 hervor. An diesen ~eaktionen wirken beide Bicyclobutan-Systeme und die Azofunktion mit.}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerbert1979, author = {Christl, Manfred and Herbert, R.}, title = {Unusual Carbon Shielding Effects of Cyclopropanes and Double Bonds in Strained Bicyclo[3.1.0]hexanes and Cyclopentenes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58038}, year = {1979}, abstract = {Carbon-13 shieldings and one-bond \(^{13}\)C-H coupling constants of bicydo[2.1.1]hexane, bicydo[2.l.l]hex- 2-ene, tricydo[3.1.1.0\(^{2.4}\)]heptane and benzvalene are presented and compared. to the data of related. compounds. H a bicydo[3.1.0]hexane system is part of a rigid skeleton, the cydopropane ring exerts spedfk: 'Y substituent eflects of two ldnds. In the case of the bicyclobexane boat form an upfield shift of the C-3 signal is observed and in tbe esse of the chair form a downfield shift of 15-20 ppm. Compared to the corresponding cydopentanes the double bond in strained cydopentenes causes downfield shifts of the C-4 absorption. 1bis eftect increases witb increasing strain, reaching 8 45.9 ppm maximum in benzvalene. Hence it is tbe only known bicydo[l.l.O]butane baving 8 reversed order of carbon shieldings. The downfield shifts are e:xplained by means of simple orbital interaction schemes.}, subject = {Organische Chemie}, language = {en} } @article{ChristlHerbert1979, author = {Christl, Manfred and Herbert, R.}, title = {Der Einfluß anellierter Ringe auf die \(^{13}\)C-NMR-chemischen Verschiebungen von Tricyclo[3.1.0.0\(^{2,6}\)]hexan- und Bicyclo[2.1.1]hexan-Derivaten}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58058}, year = {1979}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerzog1986, author = {Christl, Manfred and Herzog, C.}, title = {\(^{13}\)C-NMR-Spektroskopie: Besondere Hochfeldeffekte in Bicyclo[4.1.1]- und Tricyclo[5.1.0.0\(^{2,8}\)]octan-Systemen (1,3-Cycloheptadien-Effekt) und besondere Tieffeldeffekte in Dihalogenbicyclo[2.1.1]hex-2-enen (Cyclopenten-Effekt)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58334}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerzog1987, author = {Christl, Manfred and Herzog, C.}, title = {3-(Phenylsulfonyl)tricyclo[4.1.0.0\(^{2,7}\)]hept-4-en-3-yllithium}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58340}, year = {1987}, abstract = {Phenyl(tricyclo[4.1.0.0\^(^{2,7}\)] hept-4-en-3-yl)sulfone 8 has been prepared in two steps from 4,S-dlbromohomobenzvalene (6) and deprotonated to give the title compound 9. The carbon-13 NMR spectrum of 9 reveals a considerable interaction between the allyl anion moiety and the bicyclobutane system.}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerzogBrueckneretal.1986, author = {Christl, Manfred and Herzog, C. and Br{\"u}ckner, D. and Lang, R.}, title = {Neue Homobenzvalen-Derivate (Tricylo[4.1.0.0\(^{2,7}\)]hept-3-ene)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58241}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerzogKemmer1986, author = {Christl, Manfred and Herzog, C. and Kemmer, P.}, title = {Tricyclo[5.1.0.0\(^{2,8}\)]oct-3-en, -oct-4-en und -octan: Darstellung und Thermolyse der Hydroderivate des Octavalens}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58310}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHerzogNusser1986, author = {Christl, Manfred and Herzog, C. and Nusser, R.}, title = {Bicyclo[4.1.1]octa-2,4-dien, -oct-2-en, -oct-3-en und -octan aus Norpinen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58326}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHuisgen1973, author = {Christl, Manfred and Huisgen, R.}, title = {Orientierungsph{\"a}nomene bei der Cycloaddition aliphatischer und aromatischer Nitriloxide an α,β-unges{\"a}ttigte Carbonester}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57942}, year = {1973}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlHuisgen1968, author = {Christl, Manfred and Huisgen, R.}, title = {Alte und neue Cycloadditionen der Nitriloxide}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30237}, year = {1968}, abstract = {No abstract available}, language = {de} } @article{ChristlKemmerMattauch1986, author = {Christl, Manfred and Kemmer, P. and Mattauch, B.}, title = {1-Methylbenzvalen. Synthese und einige Reaktionen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58270}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlKraft1988, author = {Christl, Manfred and Kraft, A.}, title = {Tricyclo[3.1.1.0\(^{2,6}\)]hexandion (das Valen des o-Benzochinons), Bicyclo[2.1.1]hexan-2,3-dion und Valene eines Chinoxalins, des Phenazins sowie eines Benzophenazins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58459}, year = {1988}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlKraft1988, author = {Christl, Manfred and Kraft, A.}, title = {Tricyclo[3.1.1.0\(^{2,6}\)]hexandion (the Valen of o-Benzochinons), Bicyclo[2.1.1]hexan-2,3-dion and Valene of a Chinoxalins, of Phenazins and of a Benzophenazine}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58462}, year = {1988}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlKrimmKraft1990, author = {Christl, Manfred and Krimm, Stefan and Kraft, Arno}, title = {Some Valenes of Benzannelated Five-Membered Heteroarenes - Synthesis and NMR Spectra}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30026}, year = {1990}, abstract = {No abstract available}, language = {en} } @article{ChristlKrimmKraft1990, author = {Christl, Manfred and Krimm, Stefan and Kraft, Arno}, title = {Einige Valene von benzanellierten f{\"u}nfgliedrigen Heteroarenen - Synthesen und NMR-Spektren}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31559}, year = {1990}, abstract = {No abstract available}, language = {de} } @article{ChristlLang1982, author = {Christl, Manfred and Lang, R.}, title = {Tricyclo[5.1.0.0\(^{2,8}\)]octa-3,5-diene (Octavalene)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58124}, year = {1982}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlLangHerbertetal.1980, author = {Christl, Manfred and Lang, R. and Herbert, R. and Freitag, G.}, title = {Zusammenhang zwischen Orbitalcharakter und Reaktionsprodukt bei der Umsetzung von Benzvalen und Homobenzvalen mit Thiophenol}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58065}, year = {1980}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLangHerzog1986, author = {Christl, Manfred and Lang, R. and Herzog, C.}, title = {The Synthesis of Octavalene (Tricyclo[5.1.0.0\(^{2,8}\)]octa-3,5-diene) and Several Substituted Octavalenes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58254}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlLangLechner1980, author = {Christl, Manfred and Lang, R. and Lechner, M.}, title = {Tetra- und pentacyclische Tricyclo[4.1.0.0\(^{2,7}\)]hept-3-en-Derivate; Abfangprodukte des Tricyclo[4.1.0.0\(^{2,7}\)]hepta-3,4-diens}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58078}, year = {1980}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLangReimannetal.1984, author = {Christl, Manfred and Lang, R. and Reimann, W. and Irngartinger, H.}, title = {Darstellung und R{\"o}ntgenstrukturanalyse des Diels-Alder-Addukts von 4-Phenyl-4H-1,2,4-triazol-3,5-dion an Octavalen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58162}, year = {1984}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLangHerzogetal.1985, author = {Christl, Manfred and Lang, Reinhard and Herzog, Clemens and Stangl, Roland and Peters, Karl and Peters, Eva-Maria and Schnering, Hans Georg von}, title = {Reaktion von Homobenzvalen mit Tetracyanethylen : Bildung eines Tetracyandihydrobarbaralan- und eines Tetracyancyclopropan-Derivats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31839}, year = {1985}, abstract = {In den Reaktionen von Tetracyanethylen (TCNE) und 5,6-Dichlor-2,3-dicyan-p-benzochinon mit Benzvalen haben wir k{\"u}rzlich die ersten Beispiele f{\"u}r die lange gesuchte einstufige 1,4-Cycloaddition eines Alkens an ein Vinylcyclopropan gcfunden(I~J. Sie ist als [(.,2.+.2s)+ 112J-Prozeß der Dicls-Alder-Addition nahe verwandtllbl. Allerdings entsteht das betreffende TCNE-Addukt, ein Dihydrosemibullvalen-Derivat, nur in einer Ausbeute von wenigen Prozent. Die Hauptprodukte gehen aus einer Zwitterionischen Zwischenstufe hervor, die durch Anlagerung von TCNE an die Benzvalen-n-Bindung resultiert. Professor Rolf Huisgen zum 65. Geburtstag gewidmet}, subject = {Chemie}, language = {de} } @article{ChristlLanzendoerferHegmannetal.1985, author = {Christl, Manfred and Lanzend{\"o}rfer, F. and Hegmann, J. and Peters, K. and Peters, E.-M. and Schnering, H. G. von}, title = {Cycloadditionen von 6-0xo-l,3,4-oxadiazinen (4,5-Diaza-α-pyronen), 3 : Reaktionen von 6-Oxo-2,5-diaryl-1,3,4-oxadiazinen mit Alkenen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58191}, year = {1985}, abstract = {Das bekannte 6-0xo-2,5-diphenyl-6H-l,3,4-oxadiazin (1 a) und die neuen 2,5-Diarylderivate 1 b - g lagern Alkene an, und es entstehen stickstofIfreie Produkte. Im Falle von Cyclopropenen und Cyclobuten bilden sich die a,p-unges{\"a}ttigten Siebenring-Enollactone 42 -45 bzw. das a,ß-unges{\"a}ttigte Achtring-Enollacton 47. 42a und d erleiden an basischem Aluminiumoxid die H-Verschiebung zu den ß,y-unges{\"a}ttigten Siebenring-Enollactonen 46a bzw. d. Bei weiteren Olefinen wurden die 'Y-Ketoketene des Typs 33 als Zwischenprodukte nachgewiesen oder sind aufgrund der Konstitution der Endprodukte wahrscheinlich. Aus 1 a werden mit Norbomen, Norbornadien, Cyc1openten, trans-Cycloocten und Styrol die Sechsring-Enollactone 10, 13, 15, 19 bzw. 21 und 22 erhalten. 10 isomerisiert mit Kalium-tert-butoxid zu 34, und die Methanolyse dieser Enollactone erbringt die diastereomeren Methy]ester 12 bzw. 35. Das y-Ketoketen 16 aus trans-Cycloocten nimmt schneller Wasser und Methanol zu 17 bzw. 18 auf als es zum Enollacton 19 cyclisiert. cis,trans-l,5-Cyc1ooctadien erbringt {\"u}ber die Stufe des nachgewiesenen y-Ketoketens 40 in einer intramolekularen [2 + 2J-Cyc1oaddition den Tricyclus 41. Tetracyclische Verbindungen des Typs 4 gehen aus der Umsetzung von Benzvalen (2) mit 1 hervor. Durch R{\"o}ntgenstrukturanalysen wurden Konstitution und Konfiguration von 10, 19 und 41 aufgekl{\"a}rt}, subject = {Organische Chemie}, language = {de} } @article{ChristlLanzendoerferPetersetal.1983, author = {Christl, Manfred and Lanzend{\"o}rfer, F. and Peters, K. and Peters, E.-M. and Schnering, H. G. von}, title = {Die Reaktionen von 2,5-Diaryl-1,3,4-oxadiazin-6-onen mit trans-Cycloocten, cis,trans-Cyclooctadien und Cyclopropenen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58156}, year = {1983}, abstract = {The transient [4+2]-cycloadducts from the title components eliminate nitrogen to form a 3,4-dihydro-2-pyrone derivative, a tricyclic cyclobutanone derivative and 2,5-dihydrooxepin-2-one derivatives, respectively.}, subject = {Organische Chemie}, language = {de} } @article{ChristlLanzendoerferGroetschetal.1990, author = {Christl, Manfred and Lanzend{\"o}rfer, U. and Gr{\"o}tsch, M. M. and Ditterich, E. and Hegmann, J.}, title = {Cycloadditionen von 1,3,4-0xadiazin-6-onen (4,5-Diaza-alpha-pyronen), 9 - 6-Oxo-5-phenyl-1,3,4-oxadiazin-2-carbons{\"a}ure-methylester - Synthese und Reaktionen mit Norbornen, Norbornadien, Cyclopropenen, Cyclobuten und Benzvalen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58569}, year = {1990}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLanzendoerferGroetschetal.1985, author = {Christl, Manfred and Lanzend{\"o}rfer, U. and Gr{\"o}tsch, M. M. and Hegmann, J.}, title = {Prim{\"a}raddukt, γ-Ketoketen und einige Folgeprodukte der Reaktion von 6-Oxo-5-phenyl-1,3,4-oxadiazin-2-carbons{\"a}ure-methylester mit Norbornen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58220}, year = {1985}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLanzendoerferGroetschetal.1993, author = {Christl, Manfred and Lanzend{\"o}rfer, U. and Gr{\"o}tsch, M. M. and Hegmann, J. and Ditterich, E. and H{\"u}ttner, G. and Peters, K. and Peters, E.-M. and Schnering, H. G. von}, title = {Cycloadditionen von 6H-1,3,4-0xadiazin-6-onen (4,5-Diaza-α-pyronen), 12 - Dieckmann-Kondensationen ohne Basen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58665}, year = {1993}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLanzendoerferFreund1981, author = {Christl, Manfred and Lanzend{\"o}rfer, Ulrike and Freund, Silke}, title = {Olefinadditionen an 2,5-Diphenyl-1,3,4-oxadiazin-6-on}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-41525}, year = {1981}, abstract = {No abstract available}, language = {de} } @article{ChristlLechner1982, author = {Christl, Manfred and Lechner, M.}, title = {Einige Reaktionen des 8,8-Dibromtetracyclo[5.1.0.0\(^{2,4}\).0\(^{3,5}\)]octans}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58108}, year = {1982}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLechner1975, author = {Christl, Manfred and Lechner, M.}, title = {Zur intramolekularen Wechselwirkung von Cyclopropylidenen mit dem Bicyclo[1.1.0]butansystem}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-41509}, year = {1975}, abstract = {No abstract available}, language = {de} } @article{ChristlLeiningerKemmer1984, author = {Christl, Manfred and Leininger, H. and Kemmer, P.}, title = {{\"U}ber das cis-Glycol und das Epoxid des Benzvalens}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58174}, year = {1984}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlLeininger1979, author = {Christl, Manfred and Leininger, Hartmut}, title = {7-Azatetracyclo[4.1.0.02,4.03,5]heptan - ein neues Valenzisomeres des Azepins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30034}, year = {1979}, abstract = {No abstract available}, language = {de} } @article{ChristlLeiningerBrunn1982, author = {Christl, Manfred and Leininger, Hartmut and Brunn, Erich}, title = {Carbon-13 Nuclear Magnetic Resonance Spectra of 7-Heterotetracyclo[4.1.0.02,4.03,5]heptanes. Annelation Effects of Aziridine, Oxirane, and Thiirane Rings. Unusual gamma and delta Substituent Effects}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30010}, year = {1982}, abstract = {No abstract available}, language = {de} } @article{ChristlLeiningerBrueckner1983, author = {Christl, Manfred and Leininger, Hartmut and Br{\"u}ckner, Dieter}, title = {On the Nature of the Bicyclo [3.2.1]octa-3,6-dien-2-yl Anion: A 13C NMR spectroscopic study}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-30060}, year = {1983}, abstract = {No abstract available}, language = {en} } @article{ChristlLeiningerMattauch1983, author = {Christl, Manfred and Leininger, Hartmut and Mattauch, Brigitte}, title = {The 13C NMR Spectra of Some Tricyclo[2.2.0.02,6]hexane Derivatives : Unexpected High Field Absorptions Due to Additive gamma-anti Subsituent Effects}, isbn = {x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-41620}, year = {1983}, abstract = {By means of the BC NMR spectra of tricyclo{2.2.0~rfJ6Jhexane and thirteen of its derivatives the effects of substituents in endo-3- and endo-5-positions on the HC chemical shifts have been determined. The y-anti effects are at least as Jarge as in monosubstituted cyc1obutanes, where the shielding values of second-row hetero substituents exceed those in unstrained systems by far, and higher-row and carbon substituents still cause substantial upfield shifts. In the title system the y-anti effect of a substituent in the endo-3- and endo-5-position are operative additively, and thus shift the absorption of C-J upfieJd by a maximum of 27 ppm with respect to the unsubstituted hydrocarbon.}, language = {en} } @article{ChristlLessMueller1994, author = {Christl, Manfred and Leß, Roland and M{\"u}ller, Heinrich}, title = {6,7-Dimethylene-2,4-diphenylbicyclo[3.2.l]oct-3-en-2-yl Anion : A Test for the Origin of the Unusual Properties of the Bicyclo[3.2.l]octa-3,6-dien-2-yl Anion}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31547}, year = {1994}, abstract = {No abstract available}, language = {en} } @article{ChristlLueddeckeNagyreviNeppeletal.1977, author = {Christl, Manfred and L{\"u}ddecke, H.-J. and Nagyrevi-Neppel, A. and Freitag, G.}, title = {Einige Diels-Alder-Additionen des Benzvalens}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57992}, year = {1977}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlMattauch1985, author = {Christl, Manfred and Mattauch, B.}, title = {Versuche zur Synthese eines formalen Nitriloxid-Addukts des Benzols. 1,3-Dipolare Cycloadditionen an Bicyclo[2.2.0]hex-5-en-2,3-dicarbons{\"a}ureanhydrid, Dewarbenzol und 1,4-Cyclohexadien}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58216}, year = {1985}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlMattauchIrngartingeretal.1986, author = {Christl, Manfred and Mattauch, B. and Irngartinger, H. and Goldmann, A.}, title = {Additionen von Benzvalen an Nitriloxide. Eine Synthese f{\"u}r Benzvalen-3-carbonitril}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58269}, year = {1986}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlMueller1993, author = {Christl, Manfred and M{\"u}ller, H.}, title = {Induktiver Effekt, negative Hyperkonjugation und Gegenion sind nicht die Ursache der besonderen Eigenschaften des Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anions. - Eine NMR-Studie mit phenylsubstituierten Modellen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58655}, year = {1993}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlNusserHerzog1988, author = {Christl, Manfred and Nusser, R. and Herzog, C.}, title = {4-Bromoctavalen und zwei (Brommethylen)homobenzvalene anstelle eines erwarteten Bromoctabisvalens}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58409}, year = {1988}, abstract = {No abstract available.}, subject = {Organische Chemie}, language = {de} } @article{ChristlReichRoberts1971, author = {Christl, Manfred and Reich, H. J. and Roberts, J. D.}, title = {Nuclear Magnetic Resonance Spectroscopy. Carbon-13 Chemical Shifts of Methylcyclopentanes, Cyclopentanols, and Cyclopentyl Acetates}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57862}, year = {1971}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlReuchlein1990, author = {Christl, Manfred and Reuchlein, H.}, title = {Synthesis and NMR Spectra of 2,3-Dihydro-1,3-methanoindene Derivatives and 1,2,3,5-Tetrahydro-1,3-methanopentalene}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58557}, year = {1990}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlReuchlein1990, author = {Christl, Manfred and Reuchlein, H.}, title = {Synthesen und NMR-Spektren von 2,3-Dihydro-1,3-methanoindenderivaten und 1,2,3,5-Tetrahydro-1,3-methanopentalen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58549}, year = {1990}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlRoberts1972, author = {Christl, Manfred and Roberts, J. D.}, title = {Nuclear Magnetic Resonance Spectroscopy : Carbon-13 Chemical Shifts of Small Peptides as a Function of pH}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-57885}, year = {1972}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {en} } @article{ChristlRoberts1972, author = {Christl, Manfred and Roberts, John D.}, title = {Carbon-13 Nuclear Magnetic Resonance Spectroscopy : Conformational Analysis of Methyl-Substituted Cycloheptanes, Cycloheptanols, and Cycloheptanones}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-41663}, year = {1972}, abstract = {The 130 chemical shifts were determined of the carbons in 12 cycloheptanes, 21 cycloheptanols, and 8 cycloheptanones. In some cyc1oheptanols and cyc1oheptanones, the assignments have been obtained unambiguously by the synthesis of deuterated derivatives and the use of paramagnetic-shift reagents. Substituent effects for the different types of groups have been calculated. The most informative data about the cyc10heptane conformations were provided by the relatively well understood I' effects. The results are generally in,good agreement with predictions based on the twist-chair form, which has been predicted by Hendrickson to be the most stable conformation. Pairs of cis-trans isomers are found to have rather characteristic differences in their 130 spectra. This fact was used to assign the resonances found for cis-trans mixtures of methyl-substituted cyc1oheptanols to specific isomers.}, language = {en} } @article{ChristlSchreck1987, author = {Christl, Manfred and Schreck, M.}, title = {7-Arylbicyclo[4.2.0]oct-1-ene - Synthese durch [2+2]-Cycloadditionen von 1,2-Cyclohexadien sowie 1-Methyl-1,2-cyclohexadien und thermische {\"A}quilibrierung der exo/endo-Isomeren}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58352}, year = {1987}, abstract = {Das exo/endo--lsomerenverh{\"a}ltnis Ja: Jb bei der bekannten [2 + 2]-Cycloaddition von Styrol an 1,2-Cyclohexadien (2) wurde als tempcraturabhingiaaefunden. Der Einsatz von (Z)-Dcutcriostyrollicfene den Beweis der Zweistufiakeit dieser Reaktion, und das Diradikal 4 wird als wahrscheinlichste Zwischenstufe anaesehen. Erhitzen von Jb auf 140-170°C f{\"u}hrte zur Binstellung des thermodynamischen Gleichgewichts mit Ja (Ja:3b = 93:7), wobei wieder das Diradikal4 als Zwischenstufe fungieren d{\"u}rfte. Mit Hilfe kinetischer Messungen ermittelte man die Aktivierungsparameter f{\"u}r das System Ja~ 3b. - Aus 2 und den Abfangreagenzien p-Methoxystyrol, 1,1-Diphenylethylen sowie 1-Phenylpropen gingen mit bescheidenen Ausbeuten die Titelverbindungen 6a, b, 7 bzw. 8 hervor. Analoa zu 2 wurde sein l-Methylderivat 13 aus 6,6-Dibrom-1-methylbicyclo[3.1.0]hexan (9) durch Methyllithium freigesetzt. In Gegenwart von Styrol entstand neben den Abfanaprodukten 14a, b auch das Dimere 12 von lJ. - Die 1H-NMR-Spektren der Titelverbindungen belegen eine starre Halbsesselkonformation des Cyclohexentcils mit {\"a}quatorial anellienem Cyclobutanring.}, subject = {Organische Chemie}, language = {de} } @article{ChristlSchreck1987, author = {Christl, Manfred and Schreck, Michael}, title = {1,2,3,5,8,8a-Hexahydronaphthalin aus 1,2-Cyclohexadien}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31656}, year = {1987}, abstract = {Reaktionen von 1,3-Butadien und einigen seiner Methylderivate mit 1a und 1- Methyl-1,2-cyclohexadien 1b sowie den {\"U}bergang der [2 + 2]-Cycloaddukte 2 und 3 in das bisher unbekannte 1,2,3,5,8,8a-HexahydronaphthaJin 4a und einige seiner Methylderivate}, subject = {Chemie}, language = {en} } @article{ChristlStanglJelinekFink1992, author = {Christl, Manfred and Stangl, R. and Jelinek-Fink, H.}, title = {Zur Kenntnis der thermischen Umlagerung des Bicyclo[1.1.0]butan-Systems. Eine kinetische Studie des {\"U}bergangs von Tricyclo[4.1.0.0\(^{2,7}\)]heptanen in Bicyclo[3.2.0]hept-6-ene}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58623}, year = {1992}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} } @article{ChristlTuerkPetersetal.1994, author = {Christl, Manfred and T{\"u}rk, M. and Peters, K. and Peters, E.-M. and Schnering, H. G. von}, title = {Octahydro-1,2,3:4,5,6-dimethenopentalen-2-carbonitril, das erste Derivat eines noch unbekannten (CH)\(_{10}\)-Kohlenwasserstoffs}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58728}, year = {1994}, abstract = {No abstract available}, subject = {Organische Chemie}, language = {de} }