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Near-infrared (NIR) fluorophores are emerging tools for biophotonics because of their reduced scattering, increased tissue penetration and low phototoxicity. However, the library of NIR fluorophores is still limited. Here, we report the NIR fluorescence of two benzene-fused oligo-BODIPYs in their hexameric (H) and octameric (O) forms. These dyes emit bright NIR fluorescence (H: maxima 943/1075 nm, O: maxima 976/1115 nm) that can be excited in the NIR (H = 921 nm, O = 956 nm) or non-resonantly over a broad range in the visible region. The emission bands of H show a bathochromic shift and peak sharpening with increasing dye concentration suggesting the presence of J-aggregates. Furthermore, the emission maxima of both H and O shift up to 20 nm in solvents of different polarity. These dyes can be used as NIR ink and imaged remotely on the macroscopic level with a stand-off distance of 20 cm. We furthermore demonstrate their versatility for biophotonics by coating microscale beads and performing microrheology via NIR video particle tracking (NIR-VPT) in biopolymer (F-actin) networks. No photodamaging of the actin filaments takes place, which is typically observed for visible fluorophores and highlights the advantages of these NIR dyes.

In a combined experimental and computational study, the isomerization activity of the dinuclear palladium(I) complex [PdI (μ-Br)(Pt Bu3 )]2 towards allyl arenes, esters, amides, ethers, and alcohols has been investigated. The calculated energy profiles for catalyst activation for two alternative dinuclear and mononuclear catalytic cycles, and for catalyst deactivation are in good agreement with the experimental results. Comparison of experimentally observed E/Z ratios at incomplete conversion with calculated kinetic selectivities revealed that a substantial amount of product must form via the dinuclear pathway, in which the isomerization is promoted cooperatively by two palladium centers. The dissociation barrier towards mononuclear Pd species is relatively high, and once the catalyst enters the energetically more favorable mononuclear pathway, only a low barrier has to be overcome towards irreversible deactivation.

The use of electricity as an inexpensive and waste-free oxidant opens up new opportunities for the development of sustainable C–H functionalization reactions. Herein we summarize recent advances in the synthesis of biaryls through electrooxidative processes involving transition-metal-catalyzed ortho-directed C–H activation. A particular focus is set on electrooxidative C–H/C–M couplings and dehydrogenative couplings.1 Introduction2 Electrooxidative C–H/C–M Couplings3 Electrooxidative C–H/C–H Couplings4 Conclusion and Outlook

Climate change will decrease precipitation in summer for Central Europe. Consequently, summer drought will affect crops, especially when sown late. Studies reported superior yields of triticale com...

A series of distinct BODIPY heterooligomers (dyads, triads, and tetrads) comprising a variable number of typical green BODIPY monomers and a terminal red-emitting styryl-equipped species acting as an energy sink was prepared and subjected to computational and photophysical investigations in solvent media. An ethylene tether between the single monomeric units provides a unique foldameric system, setting the stage for a systematic study of excitation energy transfer processes (EET) on the basis of nonconjugated oscillators. The influence of stabilizing β-ethyl substituents on conformational space and the disorder of site energies and electronic couplings was addressed. In this way both the strong (Frenkel) and the weak (Forster) coupling limit could be accessed within a single system: the Frenkel limit within the strongly coupled homooligomeric green donor subunit and the Forster limit at the terminal heterosubstituted ethylene bridge. Femtosecond transient-absorption spectroscopy combined with mixed quantum-classical dynamic simulations demonstrate the limitations of the Forster resonance energy transfer (FRET) theory and provide a consistent framework to elucidate the trend of increasing relaxation lifetimes at higher homologues, revealing one of the fastest excitation energy transfer processes detected to date with a corresponding lifetime of 39 fs.

In the presence of [p-cymene)RuCl2]2, (E)-configured alkenyl bromides couple with aromatic carboxylates to form ortho-vinylbenzoic acids. This C-H vinylation proceeds in high yields without any activating phosphine ligands and has an excellent functional group tolerance. Starting from commonly available (E/Z )-mixtures of alkenyl bromides, (E)-configured vinyl arenes or dienes are formed exclusively. Mechanistic studies show that this selectivity is achieved because the (E)-configured alkenyl bromides undergo a smooth coupling, whereas the (Z)-isomers are rapidly eliminated with the formation of alkynes.

A range of unprocessed, reducing sugar substrates (mono‐, di‐, and trisaccharides) is shown to take part in a straightforward four‐step synthetic route to water‐soluble, uncharged BODIPY derivatives with unimpaired chiral integrity and high fluorescence efficiency. A wide compatibility with several postfunctionalizations is demonstrated, thus suggesting a universal utility of the multifunctional glycoconjugates, which we call GlycoBODIPYs. Knoevenagel condensations are able to promote a red‐shift in the spectra, thereby furnishing strongly fluorescent red and far‐red glycoconjugates of high hydrophilicity. The synthetic outcome was studied by X‐ray crystallography and by comprehensive photophysical investigations in several solvent systems. Furthermore, cell experiments illustrate efficient cell uptake and demonstrate differential cell targeting as a function of the integrated chiral information., Twelve sugars, differing in size and stereochemistry, were used as building blocks in a modular, efficient four‐step synthetic route to multifunctional BODIPY glycoconjugates with high fluorescence and hydrophilicity. The chiral information was transferred unchanged, thereby providing complex and distinct probes for target‐oriented binding studies and specific in vivo imaging.

BACKGROUND: Brewers spent grains (BSG) represents ≤85% of a brewery's solid waste and common disposal to landfill is increasingly more difficult. Yet BSG is a food‐grade by‐product with potential economic valorization that can significantly improve resource efficiency and reduction in carbon emissions. This study investigated valorization of BSG through the application of novel high solids hydrothermal processing technology in a small‐scale biorefinery, annexed to a brewery. It focused on three scenarios for the production of: (A) the sugar replacement xylitol; (B) prebiotic xylo‐oligosaccharide (XOS); and (C) co‐production of xylitol and XOS. Economic assessment was conducted by comparing the capital and operating expenditure from process simulations created in Aspen Plus®. The process models developed were supplemented with experimental data to improve accuracy. RESULTS: Internal rate of return (IRR) values obtained were greater than the hurdle rate of 9.7% for all scenarios when considering a conservative market price for xylitol and XOS as US$4500 t–¹, yet dedicated production of XOS was economically more favourable with a minimum required selling price (MRSP) of US$2509 t–¹ compared to US$4153 t–¹ for xylitol. Additionally, the scenario for co‐production of xylitol and XOS achieved the lowest MRSP of US$2182 t–¹. By‐products significantly contributed to 32.7%, 14.2% and 27.5% of the revenue generated in scenarios A, B and C, respectively. CONCLUSION: These results provide a good platform from which to develop the cost‐effective commercial production of XOS and xylitol from BSG. © 2021 Society of Chemical Industry

Brewers’ spent grains (BSG) make up to 85% of a brewery’s solid waste, and is either sent to landfill or sold as cheap animal feed supplement. Xylo-oligosaccharides (XOS) obtained from BSG are antioxidants and prebiotics that can be used in food formulations as low-calorie sweeteners and texturisers. The effect of extremely low acid (ELA) catalysis in liquid hot water (LHW) hydrothermal treatment (HTT) was assessed using BSG with dry matter contents of 15% and 25%, achieved by dewatering using a screw press. Batch experiments at low acid loadings of 5, 12.5 and 20 mg/g dry mass and temperatures of 120, 150 and 170 °C significantly affected XOS yield at both levels of dry mass considered. Maximum XOS yields of 76.4% (16.6 g/l) and 65.5% (31.7 g/l) were achieved from raw BSG and screw pressed BSG respectively, both at 170 °C and using 5 mg acid/g dry mass, after 15 min and 5 min, respectively. These XOS yields were obtained with BSG containing up to 63% less water and temperatures more than 20 °C lower than that reported previously. The finding confirms that ELA dosing in LHW HTT allows lowering of the required temperature that can result in a reduction of degradation products, which is especially relevant under high solid conditions. This substantial XOS production intensification through higher solid loadings in HTT not only achieved high product yield, but also provided benefits such as increased product concentrations and decreased process heat requirements.

The use of photoactivatable dyes in STED microscopy has so far been limited by two‐photon activation through the STED beam and by the fact that photoactivatable dyes are poorly solvable in water. Herein, we report ONB‐2SiR, a fluorophore that can be both photoactivated in the UV and specifically de‐excited by STED at 775 nm. Likewise, we introduce a conjugation and purification protocol to effectively label primary and secondary antibodies with moderately water‐soluble dyes. Greatly reducing dye aggregation, our technique provides a defined and tunable degree of labeling, and improves the imaging performance of dye conjugates in general., ONB‐2SIR, a photoactivatable dye resistant against two‐photon uncaging by 775 nm STED light is synthesized and used to perform STED microscopy before and after photoactivation without undesired activation by the STED light. The effects of the low water‐solubility of ONB‐2SIR on antibody conjugation was overcome by glycan labelling with defined degree of labelling (DOL) and a phase separation purification method.

Two novel Ru(II) photosensitisers sporting ethynyl-Nile Red chromophores are shown to absorb strongly in the visible region, and to have two distinct but weakly emissive states (1ILCT* and 3MLCT*). In addition a long-lived, lower energy ‘dark’ (non-emissive) triplet excited state is identified (3ILCT*) and successfully exploited for singlet oxygen generation.

Metal complexes at surfaces and interfaces play an important role in many areas of modern technology, including catalysis, sensors, and organic electronics. An important aspect of these interfaces is the possible exchange of the metal center, because this reaction can drastically alter the properties of the metal complex and thus of the interface. Here, we demonstrate that such metal exchange reactions are indeed possible and can proceed already at moderate temperatures even in the absence of solvents. Specifically, we studied the redox transmetalation of a monolayer of lead(ii)-tetraphenylporphyrin (PbTPP) with copper from a Cu(111) surface under ultrahigh-vacuum (UHV) conditions using multiple surface-sensitive techniques. Temperature-dependent X-ray photoelectron spectroscopy (XPS) reveals that the Pb/Cu exchange starts already below 380 K and is complete at 600 K. The identity of the reaction product, CuTPP, is confirmed by mass spectrometric detection in a temperature-programmed reaction (TPR) experiment. Scanning tunneling microscopy (STM) sheds light on the adsorbate structure of PbTPP at 300 K and uncovers the structural changes accompanying the transmetalation and side-reactions of the phenyl substituents. Moreover, individual free Pb atoms are observed as a product of the metal exchange.

Ab-initio, anatase titanium dioxide (TiO2) nanotubes were prepared from pristine anatase titanium dioxide (TiO2) nanoparticles via a low temperature modified stirring-hydrothermal technique. Scanning electron microscope (SEM) characterization of the as-synthesized sample depicted uniformly distributed one-dimensional nanotubular morphology, with an average length, thickness and diameter of ∼ 4 μ m , 17 nm and 20 nm, respectively. N 2 physisorption of the sample revealed two distinct peaks at mesopore and macropore scales of 3 nm and 100 nm, respectively. The specific surface area of the materials was observed to have increased from 8 m2 g−1 for the pristine to 62 m2 g−1 for the nanotubes. X-ray diffraction analysis indicated a tetragonal symmetry for the anatase TiO 2 nanotubes sample, which is similar to those reported in the literature. Core levels and elemental analyses showed the presence of titanium and oxygen in good proportion. Electrochemical performances of the TiO 2 nanotubes electrode offered good cyclic stability, good rate capability and a fairly large capacity of 160 mA h g−1 at a specific current of 36 mA g−1.

Catalyst encapsulation is examined as a means of increasing the productivity of olefin metathesis catalysts. Commercially available, cationic ruthenium metathesis catalysts were incorporated into a supramolecular resorcin[4]arene capsule. Encapsulation increased catalyst stability in water-saturated toluene, delivering higher metathesis yields than the parent, non-encapsulated Hoveyda catalyst in the same reaction medium.

The unique reactivity profile of the dinuclear PdI complex [PdI(μ-Br)tBu3P]2 as an isomerization cocatalyst has enabled orthogonal tandem processes ranging from styrene syntheses to biodiesel refin...

In pancreatic ductal adenocarcinoma (PDAC), the extracellular matrix (ECM) surrounding cancer cells forms a barrier that often limits the ability of chemotherapeutic drugs and cytotoxic immune subsets to penetrate and eliminate tumors. The dense stromal matrix protecting cancer cells, also known as desmoplasia, results from the overproduction of major ECM components such as collagens and hyaluronic acid (HA). Although candidate drugs targeting ECM components have shown promise in increasing penetration of chemotherapeutic agents, severe adverse effects associated with systemic depletion of ECM in peripheral healthy tissues limits their use at higher, more effective doses. Currently, few strategies exist that preferentially degrade ECM in tumor tissue over healthy tissues. In light of this, we have developed an attenuated, tumor-targeting Salmonella typhimurium (ST) expressing functional bacterial hyaluronidase (bHs-ST), capable of degrading human HA deposited within PDAC tumors. Our data show that bHs-ST (i) targets and colonizes orthotopic human PDAC tumors following systemic administration and (ii) is efficiently induced in vivo to deplete tumor-derived HA, which in turn (iii) significantly increases diffusion of Salmonella typhimurium within desmoplastic tumors. BHs-ST represents a promising new tumor ECM–targeting strategy that may be instrumental in minimizing off-tumor toxicity while maximizing drug delivery into highly desmoplastic tumors.

(1) Background: Sepsis still represents a major health care challenge, with mortality rates exceeding 25% in the western world. To further improve outcomes in this patient collective, new cardiovascular biomarkers present a promising opportunity as they target the paramount prognostic processes in sepsis: inflammation and ischemia. However, in contrast to cardiovascular diseases, a detailed analysis of novel biomarkers in sepsis is still lacking. (2) Objective: In this project, we aimed to perform a comparative analysis of biomarker levels in ischemic cardiovascular disease and sepsis. Analyzed markers comprised soluble suppression of tumorigenicity 2 (sST2; hemodynamics and inflammation), growth-differentiation factor 15 (GDF-15; injury, remodelling), soluble urokinase-type plasminogen activator receptor (suPAR; inflammation and remodeling) and heart-type fatty acid binding protein (H-FABP; myocardial ischemia). (3) Methods: In total, 311 patients were included in the study: 123 heart-failure (HF) patients, 60 patients with ST-segment elevation myocardial infarction (STEMI) and 53 sepsis patients. A total of 75 patients without coronary artery disease or signs of heart failure served as a control group. Plasma samples were analyzed by use of ELISA after informed consent. (4) Results: Patients with sepsis showed significantly increased plasma levels in all tested biomarkers compared to cardiovascular disease entities (sST2, suPAR, GDF-15: p < 0.001; H-FABP: compared to HF p < 0.001) and controls (sST2: 7.4-fold, suPAR: 3.4-fold, GDF-15: 6.5-fold and H-FABP: 15.3-fold increased plasma levels, p < 0.001). Moreover, in patients with sepsis, serum concentrations of sST2 and suPAR were significantly elevated in patients with HF and patients with STEMI (sST2: HF: 1.6-fold increase and STEMI: 2.5-fold increase, p < 0.001; suPAR: HF: 1.4-fold increase, p < 0.001 and STEMI: 1.4-fold increase, p < 0.01), whereas plasma levels of GDF-15 and H-FABP were markedly elevated in patients with STEMI only (GDF-15: 1.6-fold increase, H-FABP: 6.4-fold increase, p < 0.001). (5) Conclusions: All tested novel cardiac biomarkers showed significantly elevated levels in sepsis patients. Interestingly, a secretion pattern similar to STEMI was observed with regards to sST2 and HFABP. Thus, by providing an assessment tool especially covering the cardiovascular component of the disease, novel biomarkers offer a promising tool in sepsis patients.

The epithelial signaling pathways involved in damage and regeneration, and neoplastic transformation are known to be similar. We noted upregulation of argininosuccinate synthetase (ASS1) in hyperproliferative intestinal epithelium. Since ASS1 leads to de novo synthesis of arginine, an important amino acid for the growth of intestinal epithelial cells, its upregulation can contribute to epithelial proliferation necessary to be sustained during oncogenic transformation and regeneration. Here we investigated the function of ASS1 in the gut epithelium during tissue regeneration and tumorigenesis, using intestinal epithelial conditional Ass1 knockout mice and organoids, and tissue specimens from colorectal cancer patients. We demonstrate that ASS1 is strongly expressed in the regenerating and Apc-mutated intestinal epithelium. Furthermore, we observe an arrest in amino acid flux of the urea cycle, which leads to an accumulation of intracellular arginine. However, loss of epithelial Ass1 does not lead to a reduction in proliferation or increase in apoptosis in vivo, also in mice fed an arginine-free diet. Epithelial loss of Ass1 seems to be compensated by altered arginine metabolism in other cell types and the liver.

Halogen-bridged methylnaphthyl (MeNAP) palladium dimers are presented as multipurpose Pd-precursors, ideally suited for catalytic method development and preparative organic synthesis. By simply mixing with phosphine or carbene ligands, they are in situ converted into well-defined monoligated complexes. Their catalytic performance was benchmarked against state-of-the-art systems in challenging Buchwald-Hartwig, Heck, Suzuki and Negishi couplings, and ketone arylations. Their use enabled record-setting activities, beyond those achievable by optimization of the ligand alone. The MeNAP catalysts permit syntheses of tetra-ortho-substituted arenes and bulky anilines in near-quantitative yields at room temperature, allow mono-arylations of small ketones, and enable so far elusive cross-couplings of secondary alkyl boronic acids with aryl chlorides.

4-Oxobutenoic acids are useful as biologically active species and as versatile intermediates for further derivatisation. Currently, routes to their synthesis can be problematic and lack generality. Reaction conditions for the synthesis of 4-oxo-2-butenoic acid by microwave-assisted aldol-condensation between methyl ketone derivatives and glyoxylic acid have been developed. They provide the desired products in moderate to excellent yields for a wide range of substrates, by applying a simple procedure to accessible starting materials. The investigation revealed different conditions are required depending on the nature of the methylketone substituent, with aryl derivatives proceeding best using tosic acid and aliphatic substrates reacting best with pyrrolidine and acetic acid. This substituent effect is rationalised by frontier orbital calculations. Overall, this work provides methods for synthesis of 4-oxo-butenoic acids across a broad range of substrates.

Therapeutic resistance in pancreatic ductal adenocarcinoma (PDAC) can be attributed, in part, to a dense extracellular matrix containing excessive collagen deposition. Here, we describe a novel Salmonella typhimurium (ST) vector expressing the bacterial collagenase Streptomyces omiyaensis trypsin (SOT), a serine protease known to hydrolyze collagens I and IV, which are predominantly found in PDAC. Utilizing aggressive models of PDAC, we show that ST-SOT selectively degrades intratumoral collagen leading to decreases in immunosuppressive subsets, tumor proliferation and viability. Ultimately, we found that ST-SOT treatment significantly modifies the intratumoral immune landscape to generate a microenvironment that may be more conducive to immunotherapy.

The role of prostaglandin (PG) F2α has been scarcely studied in cancer. We have identified a new function for PGF2α in ovarian cancer, stimulating the production of Prostate Transmembrane Protein, Androgen Induced 1 (PMEPA1). We show that this induction increases cell plasticity and proliferation, enhancing tumor growth through PMEPA1. Thus, PMEPA1 overexpression in ovarian carcinoma cells, significantly increased cell proliferation rates, whereas PMEPA1 silencing decreased proliferation. In addition, PMEPA1 overexpression buffered TGFβ signaling, via reduction of SMAD-dependent signaling. PMEPA1 overexpressing cells acquired an epithelial morphology, associated with higher E-cadherin expression levels while β-catenin nuclear translocation was inhibited. Notwithstanding, high PMEPA1 levels also correlated with epithelial to mesenchymal transition markers, such as vimentin and ZEB1, allowing the cells to take advantage of both epithelial and mesenchymal characteristics, gaining in cell plasticity and adaptability. Interestingly, in mouse xenografts, PMEPA1 overexpressing ovarian cells had a clear survival and proliferative advantage, resulting in higher metastatic capacity, while PMEPA1 silencing had the opposite effect. Furthermore, high PMEPA1 expression in a cohort of advanced ovarian cancer patients was observed, correlating with E-cadherin expression. Most importantly, high PMEPA1 mRNA levels were associated with lower patient survival.

The exopolysaccharide capsule of Streptococcus pneumoniae is an important virulence factor, but the mechanisms that regulate capsule thickness are not fully understood. Here, we investigated the effects of various exogenously supplied carbohydrates on capsule production and gene expression in several pneumococcal serotypes. Microscopy analyses indicated a near absence of the capsular polysaccharide (CPS) when S. pneumoniae was grown on fructose. Moreover, serotype 7F pneumococci produced much less CPS than strains of other serotypes (6B, 6C, 9V, 15, and 23F) when grown on glucose or sucrose. RNA-sequencing revealed carbon source-dependent regulation of distinct genes of WT strains and capsule-switch mutants of serotypes 6B and 7F, but could not explain the mechanism of capsule thickness regulation. In contrast, 31P NMR of whole-cell extract from capsule-knockout strains (Δcps) clearly revealed the accumulation or absence of capsule precursor metabolites when cells were grown on glucose or fructose, respectively. This finding suggests that fructose uptake mainly results in intracellular fructose 1-phosphate, which is not converted to CPS precursors. In addition, serotype 7F strains accumulated more precursors than did 6B strains, indicating less efficient conversion of precursor metabolites into the CPS in 7F, in line with its thinner capsule. Finally, isotopologue sucrose labeling and NMR analyses revealed that the uptake of the labeled fructose subunit into the capsule is

Ylide-functionalized phosphine (YPhos) ligands allow the palladium-catalyzed α-arylation of alkyl ketones with aryl chlorides with record setting activity. Using a cyclohexyl-substituted YPhos ligand, a wide range of challenging ketone substrates was efficiently and selectively monoarylated under mild conditions. A newly designed YPhos ligand bearing tert-butyl groups on the coordinating phosphorus atom is already active at room temperature. The synthetic potential was demonstrated by gram-scale reactions and the succinct synthesis of e-caprolactone derivatives.

A Ru-catalyzed selective and atom-economic ortho-C–H allylation of aromatic acids with vinylcyclopropanes is reported. The reaction proceeds with selective cleavage of both a C–H and a C–C bond. A ...

A catalytic annulation is presented that provides straightforward, modular synthetic access to 3-substituted indanones from benzoic acids and α,β-unsaturated ketones. It is catalyzed by a bimetalli...

Recent contaminant monitoring in boreal wetlands situated in Alberta's Athabasca oil sands region revealed increased concentrations of polycyclic aromatic compounds (PACs) in passive sampling devices deployed in wetlands close to bitumen surface mining operations. In this study, graded concentrations of semipermeable membrane device (SPMD) extracts, collected from 4 wetlands with variable burdens of PACs, were administered to chicken and double-crested cormorant (DCCO) embryonic hepatocytes to determine effects on 7-ethoxyresorufin-O-deethylase (EROD) activity and mRNA expression. Concentrations and composition of PACs detected in SPMDs varied among sites, and the proportion of alkyl PACs was greater than parent compounds at all sites. ΣPACs was the highest in SPMDs deployed within 10 km of mining activity (near-site wetland [5930 ng SPMD-1]) compared to those ∼50 km south (far-site wetland [689 ng SPMD-1]). Measures of EROD activity and Cyp1a4 mRNA expression allowed the ranking of wetland sites based on aryl hydrocarbon receptor-mediated end points; EROD activity and Cyp1a4 mRNA induction were the highest at the near-site wetland. ToxChip PCR arrays (one chicken and one DCCO) provided a more exhaustive transcriptomic evaluation across multiple toxicological pathways following exposure to the SPMD extracts. Study sites with the greatest PAC concentrations had the most genes altered on the chicken ToxChip (12-15/43 genes). Exposure of avian hepatocytes to SPMD extracts from variably contaminated wetlands highlighted traditional PAC-related toxicity pathways as well as other novel mechanisms of action. A novel combination of passive sampling techniques and high-throughput toxicity evaluation techniques shows promise in terms of identifying hotspots of chemical concern in the natural environment.

The formation, characterization, and dye sensitized solar cell application of nickel(II), zinc(II) and cadmium(II) ferrocenyl dithiophosphonate complexes were investigated. The multidentate monoanionic ligand [S2PFc(OH)]− (L1) was synthesized. The reaction between metal salt precursors and L1 produced Ni(II) complexes of the type [Ni{S2P(Fc)(OH)}2] (1) (molar ratio 1:2), and a tetranickel(II) complex of the type [Ni2{S2OP(Fc)}2]2 (2) (molar ratio (1:1). It also produced a Zn(II) complex [Zn{S2P(Fc)(OH)}2]2 (3), and a Cd(II) complex [Cd{S2P(Fc)(OH)}2]2 (4). Complexes 1–4 were characterized by 1H and 31P NMR, FTIR and elemental analysis, and complexes 1 and 2 were additionally analyzed by X-ray crystallography. The first examples of dye-sensitized solar cells (DSSCs) co-sensitized with ferrocenyl dithiophosphonate complexes 1–4 are reported. Co-sensitization with the ruthenium dye N719, produced the dye materials (3)-N719 (η=8.30%) and (4)-N719 (η=7.78%), and they were found to have a better overall conversion efficiency than the pure Ru N719 dye standard (η=7.14%) under the same experimental conditions. The DSSCs were characterized using UV/vis, cyclic voltammetry, electrochemical impedance spectroscopy (EIS), photovoltaic- (I−V curves), and performing incident photon-to-current efficiency (IPCE) measurements.

Background Leadless pacemaker technology is a promising upcoming field in clinical rhythmology. Today, the most commonly used system in the clinical setting is the Micra™ leadless pacemaker system (Medtronic). In autopsies of patients who witnessed non-pacemaker associated death, unexpected ingrowth/encapsulation within the wall of the right ventricle was reported. The occurrence of a complete encapsulation was not expected and the process of endothelialisation remains unclear. We hypothesized, that a local inflammatory response might be the cause of these findings. The aim of our experimental in-vitro study was to investigate the effect of the Micra™ system and its single components on inflammatory processes. Methods For this purpose, whole Micra™ pacemakers were incubated in heparin plasma from 25 healthy volunteers for 48 h at 37 °C. Furthermore, 1 g gold, steel, titanium, tungsten and nitinol wires were incubated in heparin plasma for 48 h at 37 °C as well (n = 10). To detect eventual inflammatory processes, interleukin- (IL) 1β, IL-6, and tumor necrosis factor alpha (TNF-α), the chemokine IL-8 were measured using enzyme-linked immunosorbent assay (ELISA). Additionally, the level of transforming growth factor beta 1 (TGF-β1) and vascular endothelial growth factor (VEGF) were analysed. Results ELISA analyses showed that the whole Micra system leads to a significant increase in the inflammatory cytokine IL-6 which correlates with the data gained by the incubation of whole blood with the different wires. In particular, 0.5 g of tungsten showed a significant rise of IL-6 which could also be found for IL-1β and IL-8. Conclusions The in vitro study of the Micra system showed that the material composition led to an onset of inflammatory processes in whole blood. Consequently, one may speculate that the composition of Micra pacemaker may have a local inflammatory, though subclinical, effects in patients implanted with a Micra™ pacemakers.

Commercial Pdx(dba)y from various suppliers was found to vary considerably in appearance, homogeneity, purity, and catalytic activity. The Buchwald–Hartwig amination of 4-bromoanisole (5) with anil...

A rare case of a parallel kinetic resolution of racemic 1,3-disubstituted allenes by means of a rhodium-catalyzed addition to 1,3-diketones furnishing enantiopure allylic 1,3-diketones is described. Mechanistic experiments demonstrate that the different allene enantiomers react in parallel to either the diastereomeric E- or Z-allylic 1,3-diketones with the same absolute configuration of the newly formed stereogenic center. A broad substrate scope demonstrates the synthetic utility of this new method.

The recently introduced (Aza-)BOIMPY scaffold (bis(borondifluoride)-8-imidazodipyrromethene) is equipped with electron-rich β-alkoxy/α-aryl-substituted pyrrole moieties to saturate the highly electron-depleted, benzimidazole- and tetrazole-bearing meso-positions of the (Aza-)BOIMPY core. The established push-pull system gives rise to a series of compact, red- and near-infrared absorbing dyes and fluorophores with inverted high polarity compared to the native borondipyrromethene motif. The extent of conjugation of the pyrrolic α-aryl fragments with the dipyrrin core is studied by density functional theory (DFT) computations and correlated with observed red-shifts, vibronic progressions, and emission properties. In the course of the stepwise red-shift induced by more compact, electron-rich α-aryl groups, quantum yields of fluorescence decrease dramatically despite mitigated excited state relaxations. Time-dependent DFT (TDDFT) computations reveal the modes of geometrical relaxations upon excitation and their influence on fluorescence quantum yields; they also provide background information for further structural refinements.

Herein, we report the functionalization of the β-positions of deutero- and protoporphyrin IX dimethyl esters. Initial halogenations were carried out on both deutero- and protoporphyrin IX dimethyl esters. Although previously reported, vastly optimized yields with respect to deuteroporphyrin halogenation were obtained. Methods were developed for the bromination of the vinyl groups of protoporphyin IX dimethyl ester. Subsequent palladium-catalyzed coupling reactions were utilized to modify the periphery of these naturally occurring porphyrin derivatives with a variety of functionalities. The described Suzuki, Sonogashira, and "Click" reactions demonstrate the ease at which these porphyrins may be manipulated and even interchangeable, as will be discussed for one example. X-ray crystallographic analysis successfully determined the structure of two derivatives synthesized. Results identified a unique head-to-tail stacking pattern for 3,8-diphenyldeuteroporphyrin IX dimethyl ester, most likely due to the presence of additional aromatic moieties on the periphery of the porphyrin.

Isomerizing olefin metathesis is currently undergoing a transformation from laboratory curiosity to powerful synthetic concept at the heart of orthogonal tandem catalysis. In this process, an isomerization catalyst continuously moves double bonds along carbon chains, while a metathesis catalyst scrambles the residues at the C-C double bonds. This cooperative action of two catalysts can be used to access single, defined products from a complex mixture of compounds. Alternatively, it enables the transformation of uniform starting materials into complex product blends with defined, tunable properties. This concept article highlights recent developments and potential applications of this fascinating reaction concept.

A complementing Pd- and Rh-catalyzed dynamic kinetic resolution (DKR) of racemic allenes leading to N-allylated pyrazoles is described. Such compounds are of enormous interest in medicinal chemistry as certified drugs and potential drug candidates. The new methods feature high chemo-, regio- and enantioselectivities aside from displaying a broad substrate scope and functional group compatibility. A mechanistic rational accounting for allene racemization and trans-alkene selectivity is discussed.