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Die Identifikation von EGFR-Mutationen in Exon19 und Exon21 als prädiktive Biomarker, die mit einer erhöhten Sensitivität gegenüber EGFR-Inhibitoren der ersten Generation assoziiert werden konnten, leitete einen Paradigmenwechsel in der Behandlung von NSCLC-Patienten ein.[1-2] In entsprechenden Studien konnte retrospektiv gezeigt werden, dass lediglich Tumore auf die Behandlung mit Gefitinib ansprachen, wenn eine somatische EGFR-Mutation vorlag und im Umkehrschluss Patienten ohne die entsprec...
Im ersten Teil dieser Arbeit wurden die Einflüsse von Y3+Ionen auf die Struktur sowie das Phasenverhalten und spezifische thermodynamische Parameter von Modellmembransystemen verschiedener Komplexität und Ladung untersucht. Es konnte gezeigt werden, dass die Anwesenheit dieser Ionen zu einer dichteren Lipidpackung und partieller Dehydratation der Kopfgruppenregion, sowie zu einem ausgeprägten Anstieg der Gel-zu-flüssig Phasenübergangstemperatur der Lipidmembranen führt. Dies ist auf einen ges...
Interactions between proteins and ligands, which are fundamental to many biochemical processes essential to life, are mostly studied at dilute buffer conditions. The effects of the highly crowded nature of biological cells and the effects of liquid-liquid phase separation inducing biomolecular droplet formation as a means of membrane-less compartmentalization have been largely neglected in protein binding studies. We investigated the binding of a small ligand (ANS) to one of the most multifun...
The title compound, C22H22O2S2, 1, represents an example of an ortho-vanillin-based functionalized dithioether, which could be useful as a potential chelating ligand or bridging ligand for coordination chemistry. This dithioacetal 1 crystallizes in the orthorhombic space group Pbca. The phenyl rings of the benzyl groups and that of the vanillin unit form dihedral angles of 35.38 (6) and 79.77 (6)°, respectively. The crystal structure, recorded at 100 K, displays both weak intramolecula...
The crystal structure of the title compound, C10H13N·3H2O, a heterocyclic amine, was determined in the presence of water. The compound co-crystallizes with three water molecules in the asymmetric unit, which leads to the formation of hydrogen bonding in the crystal.
The polymeric title compound, [Cu2(C2H3N)2(C3H6S2)2](PF6)2, represents an example of a one-dimensional coordination polymer resulting from the reaction of [Cu(MeCN)4][PF6] with 1,3-dithiolane. The cationic one-dimensional ribbon consists of two copper(I) centers each ligated by one acetonitrile molecule and interconnected through two bridging 1,3-dithiolane ligands. One S-donor site of each ligand is κ1-bound to Cu, whereas the second S atom acts as a four-electron donor, bridging two ...
The title compound, [FePt(C12H12O)(C18H15P)(C25H22P2)(CO)2]·2C7H8·CH2Cl2 or [(OC)2Fe(μ-dppm)(μ-C(=O)C(2,4,5-C6H2Me3)=CH)Pt(PPh3)], represents an example of a diphosphane-bridged heterobimetallic dimetallacyclopentenone complex resulting from a bimetallic activation of 1-ethynyl-2,4,5-trimethylbenzene and a metal-coordinated carbonyl ligand. The bridging μ2-C(=O)C(2,4,5-C6H2Me3)=CH unit (stemming from a carbon–carbon coupling reaction between CO and the terminal alkyne) forms a five-member...
The title compound, trimethyl(tetrahydrofuran-κO)aluminium(III), [Al(CH3)3(C4H8O)], is an addition product of trimethylaluminium and tetrahydrofuran (THF). Instead of a dimeric structure, which is very common for these types of compounds, a monomeric molecular structure is observed. The C—Al—C angles in the molecule are very different from the C—Al—C angles found in dimeric molecular structures, leading to a different symmetry around the AlIII atom. The reasons for these differences...
The title compounds, [Sn3(CH3)9(OH)2(H2O)2][Sn(CH3)3(CHO2)2] (1) and [Sn3(CH3)9(OH)2]Cl·H2O (2), are partially condensed products of hydrolysed trimethyltin chloride. In the structures of 1 and 2, short cationic tristannatoxanes (C9H29O2Sn3) are bridged by a diformatotrimethyltin anion or a chloride anion, respectively. Hydrogen bridges are present and supposedly stabilize these structures against further polymerization to the known polymeric trimethyltin hydroxide. Especially notewort...
Two types of imidazole ligands were introduced both at the end of tetramolecular and into the loop region of unimolecular DNA G‐quadruplexes. The modified oligonucleotides were shown to complex a range of different transition‐metal cations including NiII, CuII, ZnII and CoII, as indicated by UV/Vis absorption spectroscopy and ion mobility mass spectrometry. Molecular dynamics simulations were performed to obtain structural insight into the investigated systems. Variation of ligand number and ...
Die vorliegende Dissertation beschäftigt sich mit der Entwicklung einer intramolekularen Alkin-(Aza-)de Mayo Reaktion, die zur Synthese von mittelgroßen anellierten cyclischen Dienonen genutzt werden kann. Als Ausgangsmaterial dienen einfach zugängliche Alkinyl-substituierte vinyloge (Thio-)Ester bzw. Imide. Entscheidend für die erfolgreiche Durchführung dieser photochemischen Reaktion ist die Verwendung einer quasi-monochromatischen Lichtquelle zur Bestrahlung. Des Weiteren begünstigt der Ei...
The synthesis of 10 water‐soluble β‐cyclodextrin‐tagged NHC‐gold(I) complexes is described. Key steps are nucleophilic substitutions, as well as, copper‐(CuAAC)‐ and ruthenium‐(RuAAC)‐catalyzed azide alkyne cycloadditions. Whereas the CuAAC reliably affords 1,4‐disubstituted 1,2,3‐triazoles, the regioselectivity of the RuAAC depends on the structure of the coupling partners. Permethylated cyclodextrin‐tagged NHC‐gold(I) complexes are soluble both in water and in organic solvents. They show ex...
Isoforms of protein kinase Akt are involved in essential processes including cell proliferation, survival, and metabolism. However, their individual roles in health and disease have not been thoroughly evaluated. Thus, there is an urgent need for perturbation studies, preferably mediated by highly selective bioactive small molecules. Herein, we present a structure‐guided approach for the design of structurally diverse and pharmacologically beneficial covalent‐allosteric modifiers, which enabl...
The C to Si and Ge exchange in bioactive compounds has often led to positive changes in the molecular properties, whereby Ge analogues are underrepresented. This is only possible at tetrahedral positions, and it is necessary for the analogue building blocks to withstand the synthetic conditions. Here, we present the synthesis of Si and Ge analogues of a TGFβ inhibiting 1,4‐dihydropyridine, which has a tetrahedral carbon in an important position for its activity. The molecular properties are c...
Ausgehend von den vorangegangenen synthetischen Studien innerhalb der Arbeitsgruppe beinhaltet diese Doktorarbeit die erste Totalsynthese der vermeintlichen Struktur von Chagosensine. Nach Widerlegung der postulierten Struktur sollten sieben weitere Diastereomere zur Aufklärung der korrekten Stereochemie führen, wobei jedoch keine der synthetisierten Verbindungen dem Naturstoff entspricht. Eingebettet in einen 16-gliedrigen Makrozyklus besitzt das faszinierende Polyketid neben den zwei ...
Die Verwendung von organometallischen Reagenzien für die Synthese von Allenen ist weit verbreitet und heutzutage sind viele Methoden für derartige Transformationen etabliert. Dazu zählt die SN2'-Substitution, die eine gut untersuchte Reaktion für die Synthese von enantiomerenreinen Allenen darstellt. Sowohl die SN2'-Substitution als auch die Cycloisomerisierung leisten einen vollständigen Chiralitätstransfer, sodass der Aufbau von Naturstoffen oder biologisch aktiven Stoffen möglich ist. In...
The presence of metal centers with often highly conserved coordination environments is crucial for roughly half of all proteins, having structural, regulatory, or enzymatic function. To understand and mimic the function of metallo-enzymes, bioinorganic chemists pursue the challenge of synthesizing model compounds with well-defined, often heteroleptic metal sites. Recently, we reported the design of tailored homoleptic coordination environments for various transition metal cations based on uni...
The success in biological screening of small molecules is largely determined by structural and molecular properties a library represents. There is a great demand for synthetic methodologies that enable delivery of novel molecular probes and lead structures for drug discovery. We developed a synthesis strategy that grants access to a range of biologically relevant novel cyclic sulfonamide scaffolds employing easily available saccharin-derived imine substrates. In our first approach, a number o...
The involvement of protein kinase CK1δ in the pathogenesis of severe disorders such as Alzheimer’s disease, amyotrophic lateral sclerosis, familial advanced sleep phase syndrome, and cancer has dramatically increased interest in the development of effective small molecule inhibitors for both therapeutic application and basic research. Unfortunately, the design of CK1 isoform-specific compounds has proved to be highly complicated due to the existence of six evolutionarily conserved human CK1 m...
The research emphases of the Ph.D. projects focus on two topics: construction of heteroleptic self-assembled cage structures based on coordination chemistry and control of London dispersion interactions in self-assembled supramolecular host-guest systems. Metal-mediated self-assembly has been heavily employed for constructing nanosized structures. For instance, supramolecular cages, formed by coordination of organic ligands and metal cations, have drawn broad interests and been intensively s...