Hannamejer8337

An efficient domino process is developed for the synthesis of diversely substituted 2,3-dihydrobenzo[b]thiophenes from 2-iodoketones using a Cu-catalyst and easily available xanthate as a sulfur surrogate in good yields. This domino method has been expanded for the synthesis of 2-acylbenzo[b]thiophenes using in situ generated iodine (I2) from by-product KI in high yields. Treatment of xanthate with the copper(ii)-catalyst reduced it to a Cu(i)-catalyst, which initiates the catalytic cycle. A possible mechanism has been proposed based on the results from XPS-analysis, an iodine color test and several other control experiments.We have investigated the self-assembly of a strong dipolar molecule (LDipCC) on the semiconducting Si(111)-B surface with scanning tunneling microscopy (STM), density functional theory (DFT) calculations and STM simulations. Although the formation of an extended two-dimensional network was clearly revealed by STM under ultra-high vacuum, the assignment of a specific STM signature to the different terminal groups from the LDipCC molecular unit required a complete analysis by numerical simulations. The overall observed assembly is explained in terms of STM contrasts associated with the molecular structure of LDipCC and the molecule-surface interactions. To distinguish the relative arrangement of the dipolar molecules within the assembly, a rational combination of experimental results and electronic structure calculations allows us to identify a single adsorbed LDipCC phase in which the molecular dipoles are homogeneously arranged into a parallel fashion on the Si(111)-B surface.Electrochemical sensors are used by millions of patients and health care providers every year, yet these measurements are hindered by compounds that also exhibit inherent redox activity. Acetaminophen (APAP) is one such interferent that falls into this extensive class. In this work, an osmium-based redox polymer was used for electrochemical detection in a sensor that was operated at a decreased voltage, allowing for decreased interference. These sensors demonstrated better selectivity (40-fold for glucose and 200-fold for lactate) for their respective analyte over APAP, possessed higher sensitivity (0.350 ± 0.006 μA mM-1 for glucose and 2.00 ± 0.05 μA mM-1 for lactate) over a broad range of analyte concentrations (50 μM-10 mM for glucose and 2-324 μM for lactate), and displayed similar operational stability (26% decrease for glucose and 29% decrease for lactate) over 7 days compared to first-generation sensors. To test this platform under biologically-relevant conditions, glucose metabolism was monitored in a model liver cell line, Alpha Mouse Liver 12 (AML12) after treatment with APAP and/or insulin. This work represents a high-resolution electrochemical biosensor for microphysiological monitoring of glucose and lactate in the presence of APAP.Evaluating nanomaterial uptake and association by cells is relevant for in vitro studies related to safe-by-design approaches, nanomedicine or applications in photothermal therapy. However, standard analytical techniques are time-consuming, involve complex sample preparation or include labelling of the investigated sample system with e.g. fluorescent dyes. selleck chemicals Here, we explore lock-in thermography to analyse and compare the association trends of epithelial cells, mesothelial cells, and macrophages exposed to gold nanoparticles and multi-walled carbon nanotubes over 24 h. The presence of nanomaterials in the cells was confirmed by dark field and transmission electron microscopy. The results obtained by lock-in thermography for gold nanoparticles were validated with inductively coupled plasma optical emission spectrometry; with data collected showing a good agreement between both techniques. Furthermore, we demonstrate the detection and quantification of carbon nanotube-cell association in a straightforward, non-destructive, and non-intrusive manner without the need to label the carbon nanotubes. Our results display the first approach in utilizing thermography to assess the carbon nanotube amount in cellular environments.Interpreting the impedance response of perovskite solar cells (PSCs) is significantly more challenging than for most other photovoltaics. This is for a variety of reasons, of which the most significant are the mixed ionic-electronic conduction properties of metal halide perovskites and the difficulty in fabricating stable, and reproducible, devices. Experimental studies, conducted on a variety of PSCs, produce a variety of impedance spectra shapes. However, they all possess common features, the most noteworthy of which is that they have at least two features, at high and low frequency, with different characteristic responses to temperature, illumination and electrical bias. The impedance response has commonly been analyzed in terms of sophisticated equivalent circuits that can be hard to relate to the underlying physics and which complicates the extraction of efficiency-determining parameters. In this paper we show that, by a combination of experiment and drift-diffusion (DD) modelling of the ion and charge carrier transport and recombination within the cell, the main features of common impedance spectra are well reproduced by the DD simulation. Based on this comparison, we show that the high frequency response contains all the key information relating to the steady-state performance of a PSC, i.e. it is a signature of the recombination mechanisms and provides a measure of charge collection efficiency. Moreover, steady-state performance is significantly affected by the distribution of mobile ionic charge within the perovskite layer. Comparison between the electrical properties of different devices should therefore be made using high frequency impedance measurements performed in the steady-state voltage regime in which the cell is expected to operate.Four open-framework Ag-Sn-S compounds K2Ag2Sn2S6 (1); K2Ag2SnS4 (2); Rb2Ag2SnS4 (3); and Cs2Ag2SnS4 (4) have been synthesized using a solvothermal method. Compound 1 possesses a unique three-dimensional (3D) structure in which Ag+ ions are two-coordinated. Compounds 2-4 have the same layered structure in which Ag+ ions are tetrahedrally coordinated. Photocatalytic degradation properties of methylene blue have been investigated and compound 1 displays excellent photodegradation activities. The photoelectric response properties, optical properties, and theoretical calculations of these compounds have also been studied.In this work, a 3D-printed metal column was developed for micro gas chromatography (GC) applications and its properties and gas separation performances were characterized. By using a Ti6Al4V grade 23 powder, a square spiral one meter-long column (3D-column) was 3D-printed on a planar substrate of 3.4 × 3.3 × 0.2 cm and then perhydropolysilazane (PHPS) was deposited as a pre-treatment agent, followed by a coating of stationary phase (OV-1) onto the inner wall of the micro-channel. The 500 μm-diameter circular channel and two 800 μm-wide ports of the 3D-column were confirmed to be uniform by 3D X-ray microscopy without any distortion. The physical and thermal properties of the 3D-column were found to be very similar to that of the standard Ti6Al4V grade 23 alloy with near zero porosity (∼0.07%). The 3D-column with pre-treatment and stationary coating demonstrated efficient separation performance of gas mixtures containing alkanes, aromatics, alcohols, and ketones compared to a bare or only pretreated 3D-column in terms of the peak shape, broadening, and resolution (R > 1) within 2-3 min. The well-matched thermal responses to the target temperatures were demonstrated at the ramping rates of 10-20 °C min-1 upto 200 °C with uniform heat distribution over the 3D-column. In addition, the column bleed profiles showed that the 3D-column with PHPS had a 71% lower baseline intensity at 350 °C than that without PHPS. The 3D-column was then employed to separate a gas mixture of twelve alkanes (C9-C18, C22, C24) without any significant column bleeding and peak tailing. Therefore, the thermal responses and stability of the 3D-column promise its applicability in high temperature GC applications.The phase behaviour of various deep eutectic systems was analysed using concurrent synchrotron powder X-ray diffraction and differential scanning calorimetry. Deep eutectic systems containing the pharmaceuticals metacetamol, 2-ethoxybenzamide or benzamide as binary mixtures with phenol revealed new crystalline phases melting either before or with crystals of phenol, highlighting their lower stabilities. Furthermore, in the phenol  2-ethoxybenzamide system it was shown that multiple metastable phases can form, highlighting the potential for the separation of a hierarchy of crystal structures with differing stabilities from eutectic systems. Through these experiments, we strengthen the idea that eutectic systems can be described by understanding the formation and stabilities of metastable co-crystalline structures. These novel results lead to a deeper understanding of the structure and thermodynamics of deep eutectic solvents, with relevance for analagous systems across materials science.The development of strategies to minimise the adverse side-effects of non-steroidal anti-inflammatory drugs (NSAIDs) remains a challenge for medicinal chemists. One such strategy is the development of NSAID-peptide prodrug conjugates and this conjugation to a peptide often confers the additional property of hydrogelation. This review summarises the work published by our research group, alongside other research groups, on supramolecular hydrogels consisting of short peptides conjugated to NSAIDs. Generally, supramolecular low molecular weight hydrogels (LMWHs) are composed of amphiteric molecules, usually consisting of short peptides attached to an aromatic capping group. When the aromatic capping group is switched for an NSAID to afford hybrid gelators, some conjugates exhibit retained or improved anti-inflammatory properties of the parent drug, and sometimes new and unexpected biological activities are observed. Conjugation to peptides often provides selective COX-2 inhibition over COX-1 inhibtion, which is key to retaining the anti-inflammatory benefits of NSAIDs whilst minimising gastric side-effects. Naproxen is the most commonly employed NSAID capping group, partly due to its similarity in structure to commonly employed naphthalene capping groups. Biomimetic approaches, where canonical amino acids are switched for non-natural amino acids such as d-amino acids or dehydroamino acids, are often employed, to tune the stability. The future direction for this area of research is discussed.A highly enantioselective [3+2] annulation of isatin-derived Morita-Baylis-Hillman (MBH) carbonates and 3-nitroindoles was enabled by a chiral DMAP-thiourea bifunctional catalyst, affording the corresponding polycyclic spirooxindoles bearing three consecutive stereocenters with good to excellent yields and enantioselectivities. Transformations of the annulation product were subsequently elaborated and the preliminary biological assays demonstrated that these artificial spirooxindoles potentially inhibited pancreatic lipase in a dose-dependent manner.