Understanding the degradation mechanisms of organic cations under basic conditions is extremely important for the development of durable alkaline energy conversion devices. Cations are key functional groups in alkaline anion exchange membranes (AAEMs), and AAEMs are critical components to conduct hydroxide anions in alkaline fuel cells. Previously, we have established a standard protocol to evaluate cation alkaline stability within KOH/CD3OH solution at 80 °C. Herein, we are using the protocol to compare 26 model compounds, including benzylammonium, tetraalkylammonium, spirocyclicammonium, imidazolium, benzimidazolium, triazolium, pyridinium, guanidinium, and phosphonium cations. The goal is not only to evaluate their degradation rate, but also to identify their degradation pathways and lead to the advancement of cations with improved alkaline stabilities.A quadrupole ion trap (QIT) mass spectrometer has been modified and coupled with tunable laser excitation and highly sensitive fluorescence detection systems to perform fluorescence studies on mass-selected ions. Gaseous ions, generated using nanoelectrospray ionization (nano-ESI), are trapped in the QIT that allows optical access for laser irradiation. The emitted fluorescence is collected from a 5.0 mm diameter hole drilled into the ring electrode of the QIT and is directed toward the detection setup. Due to the small inner diameter (7.07 mm) of the ring electrode and a relatively large opening for fluorescence collection, a fluorescence collection efficiency of 2.3% is achieved. After some losses in transmission, around 1.8% of the emitted fluorescence reaches the detectors, more than any other similar instrument reported in the literature. This improved fluorescence collection translates to a much shorter measurement time for a fluorescence signal. Another key feature of this setup is the ability to perform a variety of fluorescence experiments on trapped ions including excitation and emission spectroscopy, lifetime measurement, and ion imaging. The capabilities of the instrument are demonstrated by measuring fluorescence spectra of dyes and biomolecules labeled with dyes in a range of different excitation and emission wavelengths, quantum yields, m/z, and different polarities. A fluorescence lifetime measurement and ion image of trapped rhodamine 6G cations are also shown. With a wide array of functionality and high fluorescence detection performance, this setup provides an opportunity to study biomolecular structures and photophysics of fluorophores in well-controlled environments.We report a one-pot glycosylation strategy for achieving rapid syntheses of heptose (Hep)-containing oligosaccharides. The reported procedure was designed to incorporate an in situ phosphorylation step into an orthogonal one-pot glycosylation. Hep-containing oligosaccharides were assembled directly from building blocks with minimal effort expended on manipulation of protecting and aglycone leaving groups. The utility of our one-pot procedure was illustrated by synthesizing partial core oligosaccharide structure present in the lipopolysaccharide of Ralstonia solanacearum.Enantioselective C(sp3)-H aminations allow an efficient access to nonracemic chiral amines. This work reports the catalytic asymmetric synthesis of chiral 1,2,5-thiadiazolidine-1,1-dioxides by an enantioselective ring-closing 1,5-C-H amination of sulfamoyl azides. The reaction is catalyzed by a recently introduced simple chiral ruthenium bis(oxazoline) (pybox) complex ( Angew. Chem. Int. Ed. 2020, 59, 12395) and provides cyclic 5-membered sulfamide products in up to 98% yield and up to 98% ee if the C-H bond is in a benzylic position. Mechanistic experiments support a stepwise mechanism in which an intermediate ruthenium nitrenoid species initiates a 1,5-hydrogen atom transfer followed by an immediate radical rebound. The cyclic sulfamide products are suitable intermediates for the synthesis of chiral vicinal diamines as has been verified for a representative example.Using a quantum mechanical/molecular mechanical approach, the absorption wavelength of the retinal Schiff base was calculated based on 13 microbial rhodopsin crystal structures. The results showed that the protein electrostatic environment decreases the absorption wavelength significantly in the cation-conducting rhodopsin but only slightly in the sensory rhodopsin. Among the microbial rhodopsins with different functions, the differences in the absorption wavelengths are caused by differences in the arrangement of the charged residues at the retinal Schiff base binding moiety, namely, one or two counterions at the three common positions. Among the microbial rhodopsins with similar functions, the differences in the polar residues at the retinal Schiff base binding site are responsible for the differences in the absorption wavelengths. Counterions contribute to an absorption wavelength shift of 50-120 nm, whereas polar groups contribute to a shift of up to ∼10 nm. It seems likely that protein function is directly associated with the absorption wavelength in microbial rhodopsins.The coupling of real and momentum space is utilized to tailor electronic properties of the collinear metallic antiferromagnet Mn2Au by aligning the real space Néel vector indicating the direction of the staggered magnetization. Pulsed magnetic fields of 60 T were used to orient the sublattice magnetizations of capped epitaxial Mn2Au(001) thin films perpendicular to the applied field direction by a spin-flop transition. The electronic structure and its corresponding changes were investigated by angular-resolved photoemission spectroscopy with photon energies in the vacuum-ultraviolet, soft, and hard X-ray range. The results reveal an energetic rearrangement of conduction electrons propagating perpendicular to the Néel vector. They confirm previous predictions on the origin of the Néel spin-orbit torque and anisotropic magnetoresistance in Mn2Au and reflect the combined antiferromagnetic and spin-orbit interaction in this compound leading to inversion symmetry breaking.Praziquantel is the only available drug to treat schistosomiasis, and therefore, urgent studies must be performed to identify new anthelmintic agents. This study reports the anthelmintic evaluation of two related ent-kaurane diterpenes isolated from aerial parts of Baccharis lateralis (Asteraceae), ent-kaur-16-en-19-oic acid (1) and 15β-senecioyl-oxy-ent-kaur-16-en-19-oic acid (2) against Schistosoma mansoni in vitro and in a murine model of schistosomiasis. Both compounds exhibited in vitro activity with lethal concentration 50% (LC50) values of 26.1 μM (1) and 11.6 μM (2) as well as reduced toxicity against human cell lines, revealing a good selectivity profile, mainly with compound 2 (selectivity index > 10). Compound 2 also decreased egg production and caused morphological alterations in the parasite reproductive system. In mice infected with S. mansoni, oral treatment with compound 2 at 400 mg/kg, the standard dose used in this model of schistosomiasis, caused a significant reduction in a total worm burden of 61.9% (P less then 0.01). S. mansoni egg production, a key mechanism for both transmission and pathogenesis, was also markedly reduced. In addition, compound 2 achieved a significant reduction in hepatosplenomegaly. Therefore, the diterpene 15β-senecioyl-oxy-ent-kaur-16-en-19-oic acid (2) has an acceptable cytotoxicity profile and is orally active in a murine schistosomiasis model.Biohybrid photoelectrochemical systems in photovoltaic or biosensor applications have gained considerable attention in recent years. While the photoactive proteins engaged in such systems usually maintain an internal charge separation quantum yield of nearly 100%, the subsequent steps of electron and hole transfer beyond the protein often limit the overall system efficiency and their kinetics remain largely uncharacterized. To reveal the dynamics of one of such charge-transfer reactions, we report on the reduction of Rhodobacter sphaeroides reaction centers (RCs) by Os-complex-modified redox polymers (P-Os) characterized using transient absorption spectroscopy. RCs and P-Os were mixed in buffered solution in different molar ratios in the presence of a water-soluble quinone as an electron acceptor. Electron transfer from P-Os to the photoexcited RCs could be described by a three-exponential function, the fastest lifetime of which was on the order of a few microseconds, which is a few orders of magnitude faster than the internal charge recombination of RCs with fully separated charge. This was similar to the lifetime for the reduction of RCs by their natural electron donor, cytochrome c2. The rate of electron donation increased with increasing ratio of polymer to protein concentrations. It is proposed that P-Os and RCs engage in electrostatic interactions to form complexes, the sizes of which depend on the polymer-to-protein ratio. Our findings throw light on the processes within hydrogel-based biophotovoltaic devices and will inform the future design of materials optimally suited for this application.Although the majority of proteins used for biomedical research are produced using living systems such as bacteria, biological means for producing proteins can be advantageously complemented by protein semisynthesis or total chemical synthesis. The latter approach is particularly useful when the proteins to be produced are toxic for the expression system or show unusual features that cannot be easily programmed in living organisms. The aim of this review is to provide a wide overview of the use of chemical protein synthesis in medicinal chemistry with a special focus on the production of post-translationally modified proteins and backbone cyclized proteins.We report a visible-light-mediated benzylic C-H oxygenation reaction. The reaction is initiated by solar light or the blue LED activation of 9,10-dibromoanthracene in a reaction with oxygen and takes place at ambient temperature and air pressure. Secondary benzylic positions are oxygenated to ketones, while tertiary benzylic carbons are oxygenated to give hydroperoxides. Notably, cumene hydroperoxide is produced in a higher yield and at milder conditions than the currently employed industrial conditions.1,1,1-Trichloroethane (1,1,1-TCA) and trichloroethene (TCE) are common recalcitrant contaminants that coexist in groundwater. H2-induced reduction over precious-metal catalysts has proven advantageous, but its application to long-term continuous treatment has been limited due to poor H2-transfer efficiency and catalyst loss. Furthermore, catalytic reductions of aqueous 1,1,1-TCA alone or concomitant with TCE catalytic co-reductions are unstudied. Here, we investigated 1,1,1-TCA and TCE co-reduction using palladium nanoparticle (PdNP) catalysts spontaneously deposited on H2-transfer membranes that allow efficient H2 supply on demand in a bubble-free form. The catalytic activities for 1,1,1-TCA and TCE reductions reached 9.9 and 11 L/g-Pd/min, values significantly greater than that reported for other immobilized-PdNP systems. During 90 day continuous operation, removals were up to 95% for 1,1,1-TCA and 99% for TCE. The highest steady-state removal fluxes were 1.5 g/m2/day for 1,1,1-TCA and 1.7 g/m2/day for TCE.