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Small molecular kinase inhibitors play a key role in modern cancer therapy. Protein kinases are essential mediators in the growth and progression of cancerous tumors, rendering involved kinases an increasingly important target for therapy. However, kinase inhibitors are almost insoluble in water because of their hydrophobic aromatic nature, often lowering their availability and pharmacological efficacy. Direct drug functionalization with polar groups represents a simple strategy to improve the drug solubility, availability, and performance. Here, we present a strategy to functionalize secondary amines with oligoethylene glycol (OEG) phosphate using a one‐pot synthesis in three exemplary kinase inhibiting drugs Ceritinib, Crizotinib, and Palbociclib. These OEG‐prodrug conjugates demonstrate superior solubility in water compared to the native drugs, with the solubility increasing up to 190‐fold. The kinase inhibition potential is only slightly decreased for the conjugates compared to the native drugs. We further show pH dependent hydrolysis of the OEG‐prodrugs which releases the native drug. We observe a slow release at pH 3, while the conjugates remain stable over 96 h under physiological conditions (pH 7.4). Using confocal microscopy, we verify improved cell uptake of the drug‐OEG conjugates into the cytoplasm of HeLa cells, further supporting our universal solubility approach. [ABSTRACT FROM AUTHOR]

The functionalization of light‐emitting triarylmethyl radicals with electron‐donating moieties can significantly increase their photoluminescence quantum yield ϕ. As luminophores in light‐emitting diodes, such open‐shell radicals can be used to overcome the problem of spin‐statistics inherent to conventional closed‐shell emitters. However, so far the functionalization of triarylmethyl radicals with donors of varying strength is limited by the restricted reactivity of the triarylmethyl radical, constraining optimization of performance to empirical trial and error approaches. Here, the reliable reactivity of N‐heterocyclic donors is used in radical‐mediated aromatic substitutions, allowing to systematically investigate the effect of donor strength on the emission characteristics of triarylmethyl radicals. As a single descriptor proxy to the donor strength, the ionization energy IE of the donor moiety is employed, which is determined by density functional theory calculations. A systematic bathochromic shift of the emission wavelength λmax is observed for increasing donor strength, while maximum ϕ values are obtained for medium‐strength donors. These effects are rationalized with a simple model based on Marcus theory supported by quantum chemical calculations and electron paramagnetic resonance. This allows to understand the effect of the donor strength on both λmax and ϕ, enabling the design of improved light‐emitting radicals in the future. [ABSTRACT FROM AUTHOR]

Conjugated molecules with multiple radical centers such as the iconic Chichibabin diradicaloid hold promise as building blocks in materials for quantum sensing and quantum information processing. However, it is a considerable challenge to design simple analogues of the Chichibabin hydrocarbon that are chemically inert, exhibit high diradical character and emit light at a distinct wavelength that may offer an optical readout of the spin state in functional ensembles. Here we describe the serendipitous discovery of the stable TTM‐TTM diradicaloid, which exhibits high diradical character, a striking sky‐blue color and near‐infrared (NIR) emission (in solution). This combination of properties is unique among related diradicaloids and is due to the presence of hydrogen and chlorine atoms in "just the right positions", allowing a perfectly planar, yet predominantly benzenoid bridge to connect the two sterically stabilized radical centers. In‐depth studies of the optical and magnetic properties suggest that this structural motif could become a mainstay building block of organic spin materials. [ABSTRACT FROM AUTHOR]

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Conjugated polymers are promising active materials for batteries. Batteries not only need to have high energy density but should also combine safe handling with recyclability or biodegradability after reaching their end‐of‐life. Here, π‐conjugated polyimidazole particles are developed, which are prepared using atom economic direct arylation adapted to a dispersion polymerization protocol. The synthesis yields polyimidazole nanoparticles of tunable size and narrow dispersity. In addition, the degree of crosslinking of the polymer particles can be controlled. It is demonstrated that the polyimidazole nanoparticles can be processed together with carbon black and biodegradable carboxymethyl cellulose binder as an active material for organic battery electrodes. Electrochemical characterization shows that a higher degree of crosslinking significantly improves the electrochemical performance and leads to clearer oxidation and reduction signals of the polymer. Polyimidazole as part of the composite electrode shows complete degradation by exposure to composting bacteria over the course of 72 h. [ABSTRACT FROM AUTHOR]

Stable tris(trichlorophenyl)methyl radicals have gained interest as all-organic bioimaging agents combining fluorescent and paramagnetic properties. However, cellular uptake has so far only been reported for nanoparticles, because molecular hydrophobic trityl radicals are not soluble in aqueous media. Here, we report the synthesis and characterization of new water-soluble tris(trichlorophenyl)methyl radical derivatives exhibiting red doublet emission. Solubility in water is achieved through functionalization with oligoethylene glycol (OEG) chains. The emission behavior of OEG functionalized trityl radicals is studied in polar environments. Donor-functionalization with carbazole evokes a charge-transfer excited state that is efficiently quenched in polar solvents. In contrast, click-reaction mediated attachment of OEG-azide and trityl acetylene furnishes a triazole functionalized radical with locally excited states and emission in water. Confocal fluorescence microscopy proves successful uptake of the material by macrophages in cell culture, showing the potential of our water soluble trityl radical for fluorescence bioimaging. [ABSTRACT FROM AUTHOR]

Microgels that assemble upon issuing of a trigger open up miscellaneous applications in soft robotics, drug delivery, and life‐like materials, due to their unique physical and chemical properties. In this work, a novel hydrogel photoresist system is formulated, consisting of 2‐hydroxyethyl acrylate, ethylene glycol diacrylate, and phenyl bis(2,4,6‐trimethylbenzoyl) phosphine oxide, as well as redox‐sensitive supramolecular host‐guest association motifs. Complex and multi‐compartmented geometries with precisely located recognition motifs are printed in high resolution, resulting in multifunctional structured microgel building blocks for mesoscopic self‐assembly. An enzymatic feedback system is employed to dissipatively assemble and disassemble the redox‐active microgel building blocks in a temporally and spatially controlled pathway. The self‐assembling photoresist system is characterized in terms of the lower critical solution temperature, swelling behavior, and printability. The present work provides new perspectives for the design of tailor‐made mesoscopic microgels with customizable functionality and high applicability for various technological applications. [ABSTRACT FROM AUTHOR]

A new carbazole‐substituted bisterpyridine with pronounced delayed fluorescence is presented. While the molecular donor‐acceptor‐donor design suggests the origin of this to be thermally activated delayed fluorescence (TADF), results from various photophysical characterizations, OLED characteristics, temperature‐dependent NMR spectroscopy, and DFT calculations all point against the involvement of triplet states. The molecule exhibits blue emission at about 440 nm with two or more fast decay channels in the lower nanosecond range in both solution and thin films. The delayed emission is proposed to be caused by rotational vibrational modes. We suggest that these results are generally applicable, especially for more complex molecules, and should be considered as alternative or competitive emissive relaxation pathways in the field of organic light emitting materials. [ABSTRACT FROM AUTHOR]

Sustainable battery concepts are of great importance for the energy storage demands of the future. Organic batteries based on redox‐active polymers are one class of promising storage systems to meet these demands, in particular when combined with environmentally friendly and safe electrolytes. Deep Eutectic Solvents (DESs) represent a class of electrolytes that can be produced from sustainable sources and exhibit in most cases no or only a small environmental impact. Because of their non‐flammability, DESs are safe, while providing an electrochemical stability window almost comparable to established battery electrolytes and much broader than typical aqueous electrolytes. Here, we report the first all‐organic battery cell based on a DES electrolyte, which in this case is composed of sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) and N‐methylacetamide (NMA) alongside the electrode active materials poly(2,2,6,6‐tetramethylpiperidin‐1‐yl‐oxyl methacrylate) (PTMA) and crosslinked poly(vinylbenzylviologen) (X‐PVBV2+). The resulting cell shows two voltage plateaus at 1.07 V and 1.58 V and achieves Coulombic efficiencies of 98 %. Surprisingly, the X‐PVBV/X‐PVBV+ redox couple turned out to be much more stable in NaTFSI : NMA 1 : 6 than the X‐PVBV+/X‐PVBV2+ couple, leading to asymmetric capacity fading during cycling tests. [ABSTRACT FROM AUTHOR]