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In this study, we report the first supramolecular indicator displacement assay (IDA) based on cucurbit[n]uril (CBn) host and a [2.2]paracyclophane derivative as indicator that is operational in blood serum., In this study, we report the first supramolecular indicator-displacement assay (IDA) based on cucurbit[n]uril (CBn) hosts that is operational in blood serum. Rational design principles for host–guest chemosensing in competitively binding media were derived through detailed mathematical simulations. It was shown that currently known CBn-based chemosensing ensembles are not suited for use in highly competitive matrices such as blood serum. Conversely, the simulations indicated that a combination of cucurbit[8]uril (CB8) and an ultra-high affinity dye would be a promising IDA reporter pair for the detection of Alzheimer's drug memantine in blood serum. Therefore, a novel class of [2.2]paracyclophane-derived indicator dyes for the host CB8 was developed that possesses one of the highest host–guest affinities (Ka > 1012 M–1 in water) known in supramolecular host–guest chemistry, and which provides a large Stokes shift (up to 200 nm). The novel IDA was then tested for the detection of memantine in blood serum in a physiologically relevant sub- to low micromolar concentration range.

The carbazolophane (Czp) donor unit is introduced to the design pool of donors in TADF emitters., The carbazolophane (Czp) donor unit (indolo[2.2]paracyclophane) is introduced to the design pool of donors in thermally activated delayed fluorescence emitters. The increased steric bulk of the annelated donor unit forces an increased torsion between the carbazole and the aryl bridge resulting in a decreased ΔEST and an enhancement of the thermally activated delayed fluorescence in the triazine-containing emitter CzpPhTrz. Further, the closely stacked carbazole and benzene units of the paracyclophane show through-space π–π interactions, effectively increasing the spatial occupation for the HOMO orbital. The chiroptical properties of enantiomers of [2.2]paracyclophane reveal mirror image circular dichroism (CD) and circularly polarized luminescence (CPL) with glum of 1.3 × 10–3. rac-CzpPhTrz is a sky-blue emitter with λPL of 480 nm, a very small ΔEST of 0.16 eV and high ΦPL of 70% in 10 wt% doped DPEPO films. Sky blue-emitting OLEDs were fabricated with this new TADF emitter showing a high maximum EQE of 17% with CIE coordinates of (0.17, 0.25). A moderate EQE roll-off was also observed with an EQE of 12% at a display relevant luminance of 100 cd m–2. Our results show that the Czp donor contributes to both a decreased ΔEST and an increased photoluminescence quantum yield, both advantageous in the molecular design of TADF emitters.

Neuroinflammation is a crucial process to maintain homeostasis in the central nervous system (CNS). However, chronic neuroinflammation is detrimental, and it is described in the pathogenesis of CNS disorders, including Alzheimer's disease (AD) and depression. This process is characterized by the activation of immune cells, mainly microglia. The role of the orphan G-protein-coupled receptor 55 (GPR55) in inflammation has been reported in different models. However, its role in neuroinflammation in respect to the arachidonic acid (AA) cascade in activated microglia is still lacking of comprehension. Therefore, we synthesized a novel GPR55 antagonist (KIT 10, 0.1–25 µM) and tested its effects on the AA cascade in lipopolysaccharide (LPS, 10 ng / mL)-treated primary rat microglia using Western blot and EIAs. We show here that KIT 10 potently prevented the release of prostaglandin E2 (PGE2), reduced microsomal PGE2 synthase (mPGES-1) and cyclooxygenase-2 (COX-2) synthesis, and inhibited the phosphorylation of Ikappa B-alpha (IκB-α), a crucial upstream step of the inflammation-related nuclear factor-kappaB (NF-κB) signaling pathway. However, no effects were observed on COX-1 and -2 activities and mitogen-activated kinases (MAPK). In summary, the novel GPR55 receptor antagonist KIT 10 reduces neuroinflammatory parameters in microglia by inhibiting the COX-2/PGE2 pathway. Further experiments are necessary to better elucidate its effects and mechanisms. Nevertheless, the modulation of inflammation by GPR55 might be a new therapeutic option to treat CNS disorders with a neuroinflammatory background such as AD or depression.

Combinatorial chemistry allows for the rapid synthesis of large compound libraries for high throughput screenings in biology, medicinal chemistry, or materials science. Especially compounds from a highly modular design are interesting for the proper investigation of structure-to-activity relationships. Permutations of building blocks result in many similar but unique compounds. The influence of certain structural features on the entire structure can then be monitored and serve as a starting point for the rational design of potent molecules for various applications. Peptoids, a highly diverse class of bioinspired oligomers, suit perfectly for combinatorial chemistry. Their straightforward synthesis on a solid support using repetitive reaction steps ensures easy handling and high throughput. Applying this modular approach, peptoids are readily accessible, and their interchangeable side-chains allow for various structures. Thus, peptoids can easily be tuned in their solubility, their spatial structure, and, consequently, their applicability in various fields of research. Since their discovery, peptoids have been applied as antimicrobial agents, artificial membranes, molecular transporters, and much more. Studying their three-dimensional structure, various foldamers with fascinating, unique properties were discovered. This non-comprehensive review will state the most interesting discoveries made over the past years and arouse curiosity about what may come.

Metal-organic frameworks (MOFs) have received increased attention in recent years due to their exceptional properties and versatility. MOFs consist of metal nodes connected by organic linkers. Particularly interesting are surface-anchored films (SURMOFs), which are grown on bulk substrates. Transmission electron microscopy (TEM) is a key technique for the analysis of the structural and chemical properties of SURMOFs on the nanoscale. For TEM sample preparation, however, the SURMOF film must be detached from the bulk substrate and transferred to an electron-transparent support. This detachment process is a severe source of damage for the SURMOF film. The preparation of SURMOFs for TEM studies is thus an obstacle that has not yet been solved satisfactorily.

Additional file of ChemSpectra: a web-based spectra editor for analytical data

Addressing intracellular targets is a challenging task that requires potent molecular transporters capable to deliver various cargos. Herein, we report the synthesis of hydrophobic macrocycles composed of both amino acids and peptoid monomers. The cyclic tetramers and hexamers were assembled in a modular approach using solid as well as solution phase techniques. To monitor their intracellular localization, the macrocycles were attached to the fluorophore Rhodamine B. Most molecular transporters were efficiently internalized by HeLa cells and revealed a specific accumulation in mitochondria without the need for cationic charges. The data will serve as a starting point for the design of further cyclic peptoid-peptide hybrids presenting a new class of highly efficient, versatile molecular transporters.

The first iodine-catalyzed cyclization reaction of aliphatic primary and secondary alcohols gives access to tetrahydrofurans through an intramolecular C(sp$^{3}$)−H activation. The reaction proceeds under mild reactions using either a floodlight lamp or daylight. The formation of ubiquitous occurring tetrahydrofuran patterns has been extensively investigated in the 1960s as it was one of the first examples of a non-directed remote C−H activation. These approaches suffer from the use of toxic transition metals in overstoichiometric amounts. An attractive metal-free solution for transforming carbon-hydrogen bonds into carbon-oxygen bonds lies in applying economically and ecologically favorable iodine reagents. The presented method involves an intertwined catalytic cycle of a radical chain reaction and an iodine(I/III) redox couple by selectively activating a remote C(sp$^{3}$)−H bond under visible-light irradiation. The reaction proceeds under mild reaction conditions, is operationally simple and tolerates many functional groups giving fast and easy access to different substituted tetrahydrofurans.

Im vom MWK Baden-Württemberg geförderten Science Data Center für Molekulare Material-wissenschaften (MoMaF) wird eine Infrastruktur aufgebaut, die Forschende aus der Chemie und den Materialwissenschaften in ihrer täglichen Arbeit unterstützt und ein effizientes Forschungsdatenmanagement (FDM) ermöglicht. Diese virtuelle Arbeitsumgebung besteht aus flexibel an die Bedürfnisse der Forschenden anpassbaren Modulen, Datenanalysetools sowie Schnittstellen zu (Fach)repositorien und wird ergänzt durch Aspekte der Metadaten- beschreibung, Langzeitarchivierung und rechtliche Hilfestellungen im Umgang mit Daten. Die entwickelten Tools und Dienstleistungen werden Anwendung in unterschiedlichen Aspekten des gesamten Forschungsdatenzyklus finden und insbesondere die Ziele verfolgen, ein FAIRes Forschungsdatenmanagement zu gewährleisten und eine Verbesserung der Forschungsqualität zu ermöglichen. Ausgehend von Chemotion*1 , einem elektronischen Laborbuch (ELN) und Repositorium, das für kleine Moleküle und ihre Reaktionen optimiert ist und Kadi4Mat*2 , einem ELN für die computergestützten Materialwissenschaften, wird eine funktionell und fachlich erweiterte Infrastruktur aufgebaut. Eine ans ELN gekoppelte Feature Toolbox liefert die Möglichkeit die jeweiligen Forschungstätigkeiten digital einzufangen, wodurch signifikante Mehrwerte für den Forschungsablauf entstehen. Dabei liegt der Fokus einerseits auf dem Ausbau von Analysefunktionalitäten, andererseits wird der Forschungsgegenstand auf die makromolekulare Chemie / Oberflächenchemie und die Materialwissenschaften erweitert. Die Arbeit mit Makromolekülen erfordert eigene Tools, so muss z. B. der vorhandene Struktureditor (geeignet für kleinere Moleküle) erweitert werden. In den beiden Fachdisziplinen der Chemie und Materialwissenschaften werden umfangreiche Datenvolumina aus realen Experimenten im Labor und aus Simulationsrechnungen erzeugt und sollen vielseitig durch Datenanalyse und Datenprozessierabläufe ausgewertet und interpretiert werden. Als gemeinsame fachübergreifende Entwicklung wird die Arbeitsumgebung so aufgebaut, dass basierend auf experimentellen und computergenerierten Daten automatisierbare Simulationsabläufe realisierbar sind und durch programmatische Schnittstellen Anknüpfpunkte für weitere Analysewerkzeuge vorliegen. Die in MoMaF betrachteten Forschungsabläufe und -daten unterscheiden sich aufgrund ihrer fachspezifischen Herkunft in wesentlichen Gesichtspunkten, wie z. B. in spezifischen Workflows und Analysemethoden. Dennoch bestehen gemeinsame Nachnutzungsszenarien die eine Interoperabilität von Daten und Ergebnisse zwischen den Fachbereichen über Programmierschnittstellen erfordern. Die hieraus resultierenden Synergien liefern eine besondere Motivation zur Nutzung der entstehenden Infrastruktur. Eine Nachnutzung der in MoMaF entwickelten Softwareprodukte wird durch Open Source Lizenzen und eine enge Einbindung der Fachcommunites in die Produktentwicklung befördert, während die Nachnutzung der Forschungsdaten durch rechtliche Analysen und Empfehlungen permanent vorangetrieben wird. *1: https://chemotion.net/ *2: https://kadi4mat.iam-cms.kit.edu/