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This thesis showcases the donor-site engineering in PdII-mediated coordination complexes, yielding distinctive supramolecular architectures, including the molecular cage, bowl, ring and capsule focuses on the donor-site-controlled self-assembly of supramolecules as well as their distinct fullerene binding abilities. Afterwards, the assembled cage is able to selectively bind C60 from fullerene soot, and develops into a recyclable system of C60 purification controlled by solvent effects. The no...
Fullerenes and their derivatives are of tremendous technological relevance. Synthetic access and application are still hampered by tedious purification protocols, peculiar solubility, and limited control over regioselective derivatization. We present a modular self-assembly system based on a new low-molecular-weight binding motif, appended by two palladium(II)-coordinating units of different steric demands, to either form a [Pd2L14]4+ cage or an unprecedented [Pd2L23(MeCN)2]4+ bowl (with L1 =...
Deregulation of cellular metabolism has been well established as one hallmark of cancer. Increased aerobic glycolysis in cancer cells, termed the Warburg effect, is associated with an overexpression of different glucose transporter isoforms, especially GLUT-1 but also GLUT-3. To date, numerous GLUT inhibitors have been reported to induce cell death in cancer, yet improvement of selectivity and potency as well as unspecific toxicity of such inhibitors remain major challenges. The piperazin-2-o...
Supramolecular coordination cages, assembled from square-planer cations (PdII or PtII) and banana-shaped ligands, have been widely studied in the past decades. Interests in this field gradually shifted from structure to function. This thesis explores the self-assembly of light-switchable homo- and hetero-leptic cages formed by Diarylethene (DAE) ligands which enable a fast photo-responsive interconversion between a flexible open form and rigid closed form of the chromophore backbone. In addit...
We report a complex system of heteroleptic coordination cages based on the combination of four bismonodentate ligands whose backbones only slightly differ in shape and length. cis-[Pd2L2L’2] assemblies cleanly form after addition of PdII cations to a 1 : 1 mixture of two shape-complementary ligands, each. When three or even all four ligands are used in combination, the unambiguous discrimination of all individual species in the product mixture becomes difficult by conventional NMR spectro...
The aim of the present work was the preparation of ultrathin silane films from the gas phase. For this purpose, a system analogous to the chemical thin-film process was developed in which silane monomers were evaporated and subsequently adsorbed on a water surface. Subsequent autopolymerization at the boundary phase allowed the creation of the ultrathin, permanently cross-linked films. Octadecyltrichlorosilane was used as the standard monomer. The resulting networks, as well as the course of ...
Im Jahr 2004 wurde das Polyketid (‒)-Lytophilippin A, welches eine eindrucksvolle Struktur und große Anzahl von stereogenen Kohlenstoffatomen (17) aufweist, durch Řezanka, Hanuš und Dembitsky aus dem Nesseltier Macrorhynchia philippina isoliert und charakterisiert. 2011 veröffentlichten Lee et al. die erste Totalsynthese von (‒)-Lytophilippin A und stellten dabei über den Vergleich der NMR-Daten fest, dass die von Řezanka et al. postulierte Struktur oder Konfiguration fehlerhaft sei. Ein Hin...
The genetic incorporation of unnatural amino acids (UAAs) into proteins by amber suppression technology provides unique avenues to study protein structure, function and interactions both in vitro and in living cells and organisms. This approach has been particularly useful for studying mechanisms of epigenetic chromatin regulation, since these extensively involve dynamic changes in structure, complex formation and posttranslational modifications that are difficult to access by traditional app...
5-Formylcytosine (5fC) is an epigenetic nucleobase of mammalian genomes that occurs as intermediate of active DNA demethylation. 5fC uniquely interacts and reacts with key nuclear proteins, indicating functions in genome regulation. Transcription-activator-like effectors (TALEs) are repeat-based DNA binding proteins that can serve as probes for the direct, programmable recognition and analysis of epigenetic nucleobases. However, no TALE repeats for the selective recognition of 5fC are availab...
The automated comparison of protein-ligand binding sites provides useful insights into yet unexplored site similarities. Various stages of computational and chemical biology research can benefit from this knowledge. The search for putative off-targets and the establishment of polypharmacological effects by comparing binding sites led to promising results for numerous projects. Although many cavity comparison methods are available, a comprehensive analysis to guide the choice of a tool for a s...
Site-directed spin labeling (SDSL) in combination with electron paramagnetic resonance (EPR) spectroscopy enables studies of the structure, dynamics, and interactions of proteins in the noncrystalline state. The scope and analytical value of SDSL–EPR experiments crucially depends on the employed labeling strategy, with key aspects being labeling chemoselectivity and biocompatibility, as well as stability and spectroscopic properties of the resulting label. The use of genetically encoded ...
Transcription-activator-like effectors (TALEs) are repeat-based proteins featuring programmable DNA binding. The repulsion of TALE repeats by 5-methylcytosine (5mC) and its oxidized forms makes TALEs potential probes for their programmable analysis. However, this potential has been limited by the inability to engineer repeats capable of actual, fully selective binding of an (oxidized) 5mC: the extremely conserved and simple nucleobase recognition mode of TALE repeats and their extensive i...
Many pathogenic bacteria produce virulence factors that act as pore-forming toxins (PFTs) on the cytoplasmic membrane of target hosts. PFTs can be distinguished in binary (AB) toxins that actively transport a toxic counterpart into the cell and in conventional PFTs, which perforate the host membrane and translocate ions. Upon membrane interaction, the PFTs provoke different effects such as abolishing the transmembrane potential, altering signal pathways or disruption of the cell cytoskeletal....
Krebs kommt aufgrund der stetig steigenden Anzahl an Neuerkrankungen und Todesfällen eine immer größer werdende Bedeutung in der Gesellschaft zu.1 In jüngerer Vergangenheit wurde die therapeutische Behandlung dieser Erkrankung durch den vielversprechenden Ansatz der sogenannten Präzisionsmedizin revolutioniert. Die Onkologie erlebt einen Wandel vom Einsatz klassischer unspezifischer Zytostatika hin zu einer Biomarker-adaptierten, zielgerichteten Adressierung onkogener Zielstrukturen.3 Die Pro...
A new series of [Pd2(L)4] cages based on photochromic dithienylethene (DTE) ligands allowed us to gain insight into the successive photoswitching of multiple DTE moieties in a confined metallo‐supramolecular assembly. Three new X‐ray structures of [Pd2(o‐L4)4], [Pd2(o‐L1)2(c‐L1)2] and [Pd2(c‐L1)4] (o‐L and c‐L = open and closed forms of DTE ligands, respectively) were obtained. The structures deliver snapshots of three different combinations of DTE photoisomeric states within the cage, facili...
Chiral nanosized confinements play a major role for enantioselective recognition and reaction control in biological systems. Supramolecular self‐assembly gives access to artificial mimics with tunable sizes and properties. Herein, a new family of [Pd2L4] coordination cages based on a chiral [6]helicene backbone is introduced. A racemic mixture of the bis‐monodentate pyridyl ligand L1 selectively assembles with PdII cations under chiral self‐discrimination to an achiral meso cage, cis‐[Pd2L1P2...
Ras proteins, most notably isoform KRas4B are frequently mutated oncogenes in numerous human cancers and associated with poor prognosis. Despite ambitious research affords since the discovery of Ras proteins as human oncogenes in 1982, no pharmacological therapy approach reached the clinic yet and Ras is still viewed as “undruggable” protein. For signal propagation, Ras proteins have to be localized at the plasma membrane. Enrichment there is facilitated by spatial cycles that utilize the pre...
The reaction of sodium chloride with 2-[bis(2-hydroxyethyl)amino]ethan-1-ol results in the formation of the title salt {[Na{N(CH2CH2OH)3}]Cl}n. The polymeric structure is characterized by a sodium cation coordinated by one nitrogen and five oxygen atoms in a distorted octahedral environment. The resulting one-dimensional {—O—Na—O—Na—O}— coordination polymer extends parallel to [010] and is connected through the chloride counter-anion via O—H...Cl hydrogen bonding, giving rise to a two-...
Protein ligand interaction fingerprints are a powerful approach for the analysis and assessment of docking poses to improve docking performance in virtual screening. In this study, a novel interaction fingerprint approach (PADIF, protein per atom score contributions derived interaction fingerprint) is presented which was specifically designed for utilising the GOLD scoring functions’ atom contributions together with a specific scoring scheme. This allows the incorporation of known protein–lig...
The title compound, C18H22, is a coupling product of two metallated mesitylene molecules. The dihedral angle between the aromatic rings is 11.10 (5)° and the Car—Cm—Cm—Car (ar = aromatic and m = methylene) torsion angle is 179.60 (14)°. No directional interactions beyond normal van der Waals contacts could be identified in the crystal. To our best knowledge, it is the first known coupling product of metallated mesitylene.