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The quest for effective technologies to reduce SO2 pollution is crucial due to its adverse effects on the environment and human health. Markedly, removing a ppm level of SO2 from CO2‐containing waste gas is a persistent challenge, and current technologies suffer from low SO2/CO2 selectivity and energy‐intensive regeneration processes. Here using the molecular building blocks approach and theoretical calculation, we constructed two porous organic polymers (POPs) encompassing pocket‐like structures with exposed imidazole groups, promoting preferential interactions with SO2 from CO2‐containing streams. Markedly, the evaluated POPs offer outstanding SO2/CO2 selectivity, high SO2 capacity, and an easy regeneration process, making it one of the best materials for SO2 capture. To gain better structural insights into the notable SO2 selectivity of the POPs, we used dynamic nuclear polarization NMR spectroscopy (DNP) and molecular modelling to probe the interactions between SO2 and POP adsorbents. The newly developed materials are poised to offer an energy‐efficient and environment‐friendly SO2 separation process while we are obliged to use fossil fuels for our energy needs. [ABSTRACT FROM AUTHOR]

Inverse sandwich complexes of Yb and Sm stabilized by a bulky β‐diketiminate (BDI) ligand have been prepared: (BDI)Ln(η6,η6‐C6H6)Ln(BDI); Ln=lanthanide. Coordinated benzene ligands can be neutral, di‐anionic or, often controversially discussed, even tetra‐anionic. The formal charge on benzene is correlated to assignment of the metal oxidation state which generally poses a problem. Herein, we take advantage of the structural similarities found when comparing CaII with YbII, and SrII with SmII complexes. In this work, we found an excellent overlap of the Ca/Yb inverse sandwich structures but a striking difference for the Sr/Sm pair. The much shorter Sm−N and Sm‐C6H6 distances are strong evidence for a SmIII‐benzene−4‐SmIII assignment. This was further supported by NMR spectroscopy, magnetic susceptibility, reactivity and comprehensive computational investigation. [ABSTRACT FROM AUTHOR]

Inverse sandwich complexes of Yb and Sm stabilized by a bulky β‐diketiminate (BDI) ligand have been prepared: (BDI)Ln(η6,η6‐C6H6)Ln(BDI); Ln=lanthanide. Coordinated benzene ligands can be neutral, di‐anionic or, often controversially discussed, even tetra‐anionic. The formal charge on benzene is correlated to assignment of the metal oxidation state which generally poses a problem. Herein, we take advantage of the structural similarities found when comparing CaII with YbII, and SrII with SmII complexes. In this work, we found an excellent overlap of the Ca/Yb inverse sandwich structures but a striking difference for the Sr/Sm pair. The much shorter Sm−N and Sm‐C6H6 distances are strong evidence for a SmIII‐benzene−4‐SmIII assignment. This was further supported by NMR spectroscopy, magnetic susceptibility, reactivity and comprehensive computational investigation. [ABSTRACT FROM AUTHOR]

This work concerns the isomerization of the product obtained by dimerization of methyl 4‐nitrocinnamate. Subsequent isomerization was performed using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as a base to obtain the corresponding ζ‐ and δ‐truxinate derivatives. The process was monitored by 1H NMR spectroscopy in different deuterated solvents with a wide range of dielectric constants, acetonitrile‐d3, acetone‐d6, tetrahydrofuran‐d8, and benzene‐d6. Each solvent was found to have a distinct influence on the reaction's rate constant k, with acetone‐d6 yielding the highest ratio of ζ‐truxinate derivative. Kinetic analysis of the reaction provided valuable information about the mechanism involved in the isomerization process. [ABSTRACT FROM AUTHOR]

While π‐complexes of C=C bonds are ubiquitous in organometallic chemistry, analogous complexes of the isoelectronic but strongly polarized B=N double bond of aminoboranes are extremely scarce. To address this gap, a diphosphine‐aminoborane ligand (PhDPBAiPr) is introduced and its coordination with group 10 metals is investigated. The B=N bond does not coordinate to the metal in Pt(0) and Pd(II) complexes. In contrast, side‐on coordination of the B=N bond is observed in the Ni(0) complex (PhDPBAiPr)Ni(NCPh), and the X‐ray crystal structure reveals B−N bond elongation compared to the free ligand. The choice of co‐ligand strongly influences the presence or absence of side‐on coordination at Ni(0) as evidenced by NMR spectroscopy. While the B=N π‐complex is geometrically similar to C=C analogues, a bonding analysis reveals that the interaction of the B=N motif with the electron‐rich Ni(0) center is best described as 3c4e hyperbond, in which Ni and N are competing for the empty orbital on B. [ABSTRACT FROM AUTHOR]

Chemical activation of the nuclear singlet state of dihydrogen, para‐hydrogen, can dramatically increase the sensitivity of magnetic resonance spectroscopy and imaging. Here, we show that the highly reversible activation of para‐hydrogen by an iridium pyridylpyrrolide complex is capable of producing this hyperpolarisation effect. Bound alkene ligands exhibit signal enhancement without reduction to alkanes, which is in contrast to the most widely used hyperpolarisation catalysts. The complex is recoverable due to the highly reversible binding and release of H2, and result in enhanced hydride signals in a wide range of coordinating and non‐coordinating deuterated solvents. Synthetic modification of the ligand substituents and the addition of co‐ligands show a strong dependence of chemical structure on reactivity, which reveals an untapped potential to exploit pyridylpyrrolides as ligands in the development of tunable para‐hydrogen induced hyperpolarisation catalysts or molecular probes. [ABSTRACT FROM AUTHOR]

A series of rigid polystyrene‐based photoelastomers, named sty‐PM‐x, with bionic catechol pendants were synthesized through atom transfer radical polymerization (ATRP) and deprotection techniques. These polymers were characterized using nuclear magnetic resonance spectroscopy, gel permeation chromatography, and thermogravimetric analysis. Additionally, photophysical properties of the polymers were investigated using UV‐visible absorption spectroscopy and fluorescence emission spectroscopy. Mechanical properties were evaluated through tensile tests, while interfacial adhesion was determined through cross‐cut tests. Experimental results reveal that photoelastomers, sty‐PM‐x, exhibit excellent photophysical properties, stretchability, and interfacial adhesion. This discovery provides a new perspective for the preparation of stretchable organic electroluminescent materials. [ABSTRACT FROM AUTHOR]

Dynamic nuclear polarization (DNP) offers significant signal enhancement compared to conventional nuclear magnetic resonance (NMR) in measuring the nuclear Overhauser effect. Owing to this enhancement, DNP enables the quantitative analysis of solvent–solute interactions, which are typically challenging to assess using standard NMR techniques. However, current experimental setups generally require the use of samples with relatively high solute concentrations because of large dilution factors. This limits the studies on solvent–solute interactions for bio‐related molecules, particularly those with low solubility. In such cases, the concentration of solute post‐dilution often falls below the detection limits. Herein, we introduce a novel dual injection system designed to considerably increase the dilution factor, thereby enabling the use of samples with lower solute concentrations while maintaining detectable signal levels. The effectiveness of this system was demonstrated in experiments using trifluoroacetic acid at concentrations 50 times lower than those used in the conventional method. [ABSTRACT FROM AUTHOR]

An amide‐based covalent organic framework (COF) was successfully synthesized using the reaction between 1,3,5‐trimesoyl chloride and ethylenediamine. The structure and morphology of the COF were characterized using Fourier‐transform infrared spectra, nuclear magnetic resonance spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and Brunauer‐Emmett‐Teller surface area analysis. The COF was employed as a solid‐phase extraction adsorbent for the sampling and preconcentration of chlorophenols from industrial wastewater samples prior to high‐performance liquid chromatography with ultraviolet detection. The experimental parameters influencing the extraction efficiency including type and volume of eluent solvent, sample solution volume, salt concentration, sample flow rate, and sample solution pH were investigated and optimized using a response surface methodology employing Box‐Behnken‐design. Under optimized conditions, calibration curves exhibited good linearities over the range of 0.003–10 µg/mL with determination coefficients (R2) ranging from 0.9982 to 0.9999. The method's limits of detection ranged from 0.001 to 0.01 µg/mL. Good repeatability was achieved with relative standard deviations below 4.7%. The developed procedure utilizing the COF adsorbent was successfully applied to determine chlorophenols accurately and precisely in various industrial wastewater samples. [ABSTRACT FROM AUTHOR]

It has been assumed that exercise intensity variation throughout a cycling time trial (TT) occurs in alignment of various metabolic changes to prevent premature task failure. However, this assumption is based on target metabolite responses, which limits our understanding of the complex interconnection of metabolic responses during exercise. The current study characterized the metabolomic profile, an untargeted metabolic analysis, after specific phases of a cycling 4‐km TT. Eleven male cyclists performed three separated TTs in a crossover counterbalanced design, which were interrupted at the end of the fast‐start (FS, 600 ± 205 m), even‐pace (EP, 3600 ± 190 m), or end‐spurt (ES, 4000 m) phases. Blood samples were taken before any exercise and 5 min after exercise cessation, and the metabolomic profile characterization was performed using Nuclear Magnetic Resonance metabolomics. Power output (PO) was also continually recorded. There were higher PO values during the FS and ES compared to the EP (all p < 0.05), which were accompanied by distinct metabolomic profiles. FS showed high metabolite expression in TCA cycle and its related pathways (e.g., glutamate, citric acid, and valine metabolism); whereas, the EP elicited changes associated with antioxidant effects and oxygen delivery adjustment. Finally, ES was related to pathways involved in NAD turnover and serotonin metabolism. These findings suggest that the specific phases of a cycling TT are accompanied by distinct metabolomic profiles, providing novel insights regarding the relevance of specific metabolic pathways on the process of exercise intensity regulation. Highlights: Untargeted metabolomic profile analysis may reveal unexplored bioenergetic pathways activated throughout a self‐paced cycling time trial.Exercise intensity variations throughout a cycling time trial are accompanied by different blood serum metabolomic profiles.The current new insights may encourage future investigation on the underpinning mechanisms of specific metabolomic profiles according to each time trial phase. [ABSTRACT FROM AUTHOR]

In this work, it is proposed the development of organic semiconductors (OS) based on uranyl(VI) complexes. The above by means of the synthesis and the characterization of the complexes by Infrared spectroscopy, Nuclear magnetic resonance spectroscopy, mass spectrometry, and X‐ray diffraction. Films of these complexes were deposited and subsequently, topographic and structural characterization was carried out by Scanning Electron Microscopy, X‐ray diffraction, and Atomic Force Microscopy. Additionally, the nanomechanical evaluation was performed to know the stiffness of uranyl films using their modulus of elasticity. Also, the optical characterization took place in the devices and their bandgap value ranges between 2.40 and 2.93 eV being the minor for the film of the uranyl complex with the N on pyridine in position 4 (2 c). Finally, the electrical behavior of the uranyl(VI) films was evaluated, and important differences were obtained: the uranyl complex with the N on pyridine in position 2 (2 a) film is not influenced by changes in lighting and its current density is in the order of 10−3 A/cm2. The film with uranyl complex with the N on pyridine in position 3 (2 b) and 2 c presents a greater current flow under lighting conditions and two orders of magnitude larger than in film 2 a. In these films 2 b and 2 c, ohmic behavior occurs at low voltages, while at high voltages the charge transport changes to space‐charge limited current behavior. [ABSTRACT FROM AUTHOR]

Performance fatigability is typically experienced as insufficient energy to complete daily physical tasks, particularly with advancing age, often progressing toward dependency. Thus, understanding the etiology of performance fatigability, especially cellular‐level biological mechanisms, may help to delay the onset of mobility disability. We hypothesized that skeletal muscle energetics may be important contributors to performance fatigability. Participants in the Study of Muscle, Mobility and Aging completed a usual‐paced 400‐m walk wearing a wrist‐worn ActiGraph GT9X to derive the Pittsburgh Performance Fatigability Index (PPFI, higher scores = more severe fatigability) that quantifies percent decline in individual cadence‐versus‐time trajectory from their maximal cadence. Complex I&II‐supported maximal oxidative phosphorylation (max OXPHOS) and complex I&II‐supported electron transfer system (max ETS) were quantified ex vivo using high‐resolution respirometry in permeabilized fiber bundles from vastus lateralis muscle biopsies. Maximal adenosine triphosphate production (ATPmax) was assessed in vivo by 31P magnetic resonance spectroscopy. We conducted tobit regressions to examine associations of max OXPHOS, max ETS, and ATPmax with PPFI, adjusting for technician/site, demographic characteristics, and total activity count over 7‐day free‐living among older adults (N = 795, 70–94 years, 58% women) with complete PPFI scores and ≥1 energetics measure. Median PPFI score was 1.4% [25th–75th percentile: 0%–2.9%]. After full adjustment, each 1 standard deviation lower max OXPHOS, max ETS, and ATPmax were associated with 0.55 (95% CI: 0.26–0.84), 0.39 (95% CI: 0.09–0.70), and 0.54 (95% CI: 0.27–0.81) higher PPFI score, respectively. Our findings suggested that therapeutics targeting muscle energetics may potentially mitigate fatigability and lessen susceptibility to disability among older adults. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of three families of coordination complexes synthesized from 4′‐phenyl‐2,2′:6′,2′′‐terpyridine (8, Ph‐TPY), 4′‐(4‐chlorophenyl)‐2,2′:6′,2′′‐terpyridine (9, ClPh‐TPY) and 4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine (10, MeOPh‐TPY) ligands with the divalent metals Co2+, Fe2+, Mn2+ and Ni2+ are reported. The compounds were synthesized from a 1:2 mixture of the metal and ligand, resulting in a series of complexes with the general formula [M(R‐TPY)2](ClO4)2 (where M = Co2+, Fe2+, Mn2+ and Ni2+, and R‐TPY = Ph‐TPY, ClPh‐TPY and MeOPh‐TPY). The general formula and structural and supramolecular features were determinated by single‐crystal X‐ray diffraction for bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)nickel(II) bis(perchlorate), [Ni(C21H15N3)2](ClO4)2 or [Ni(Ph‐TPY)2](ClO4)2, bis[4′‐(4‐methoxyphenyl)‐2,2′:6′,2′′‐terpyridine]manganese(II) bis(perchlorate), [Mn(C22H17N3O)2](ClO4)2 or [Mn(MeOPh‐TPY)2](ClO4)2, and bis(4′‐phenyl‐2,2′:6′,2′′‐terpyridine)manganese(II) bis(perchlorate), [Mn(C21H15N3)2](ClO4)2 or [Mn(Ph‐TPY)2](ClO4)2. In all three cases, the complexes present distorted octahedral coordination polyhedra and the crystal packing is determined mainly by weak C—H...π interactions. All the compounds (except for the Ni derivatives, for which FT–IR, UV–Vis and thermal analysis are reported) were fully characterized by spectroscopic (FT–IR, UV–Vis and NMR spectroscopy) and thermal (TGA–DSC, thermogravimetric analysis–differential scanning calorimetry) methods. [ABSTRACT FROM AUTHOR]

Several series of novel biheterocyclic compounds have been synthesized starting from 3‐alkoxy‐1H‐pyrazole‐4‐carbaldehydes and employing different types of multicomponent reactions. The structures of the obtained 4‐(pyrazol‐4‐yl)pyrano[2,3‐c]pyrazole, 4‐(pyrazol‐4‐yl)pyrazolo[4′,3′:5,6]pyrano[2,3‐b]quinoline, 4‐(pyrazol‐4‐yl)pyridine, and 4‐[(pyrazol‐4‐yl)methylidene]‐1,2‐oxazole derivatives were thoroughly characterized and confirmed using detailed nuclear magnetic resonance spectroscopy (NMR), high‐resolution mass spectrometry (HRMS), infrared spectroscopy (IR), and X‐ray analysis. [ABSTRACT FROM AUTHOR]

A Pt‐ZSM5 catalyst, coked during propane dehydrogenation and regenerated with lean air, was studied by various in‐situ and ex‐situ methods. A newly developed isothermal ceramic flat‐bed reactor with inert surfaces is described and used in the experiments. Comparative measurements successfully demonstrated that temperature alone has no effect on the catalyst and that changes in conversion and selectivity are due to coke formation. Nuclear magnetic resonance (NMR) studies using triphenylphosphine probe molecules of activated and deactivated samples showed the localization of the Pt clusters inside and outside the zeolite pores. It was shown that the Pt clusters are mainly located inside the zeolites and that the mobilization of Pt by contact with oxygen leads to permanent aging. [ABSTRACT FROM AUTHOR]

Benchtop NMR provides improved accessibility in terms of cost, space, and technical expertise. In turn, this encourages new users into the field of NMR spectroscopy. Unfortunately, many interesting samples in education and research, from beer to whole blood, contain significant amounts of water that require suppression in 1H NMR in order to recover sample information. However, due to the significant reduction in chemical shift dispersion in benchtop NMR systems, the sample signals are much closer to the water resonance compared to those in a corresponding high‐field NMR spectrum. Therefore, simply translating solvent suppression experiments intended for high‐field NMR instruments to benchtop NMR systems without careful consideration can be problematic. In this study, the effectiveness of several popular water suppression schemes was evaluated for benchtop NMR applications. Emphasis is placed on pulse sequences with no, or few, adjustable parameters making them easy to implement. These fall into two main categories: (1) those based on Pre‐SAT including Pre‐SAT, PURGE, NOESY‐PR, and g‐NOESY‐PR and (2) those based on binomial inversion including JRS and W5‐WATERGATE. Among these schemes, solvent suppression sequences based on Pre‐SAT offer a general approach for easy solvent suppression for samples with higher analyte concentrations (sucrose standard and Redbull™). However, for human urine, binomial‐like sequences were required. In summary, it is demonstrated that highly efficient water suppression approaches can be implemented on benchtop NMR systems in a simple manner, despite the limited spectral dispersion, further illustrating the potential for widespread implementation of these approaches in education and research. [ABSTRACT FROM AUTHOR]

Benchtop diffusion nuclear magnetic resonance (NMR) spectroscopy was used to perform quantitative monitoring of enzymatic hydrolysis. The study aimed to test the feasibility of the technology to characterize enzymatic hydrolysis processes in real time. Diffusion ordered spectroscopy (DOSY) was used to measure the signal intensity and apparent self‐diffusion constant of solubilized protein in hydrolysate. The NMR technique was tested on an enzymatic hydrolysis reaction of red cod, a lean white fish, by the endopeptidase alcalase at 50°C. Hydrolysate samples were manually transferred from the reaction vessel to the NMR equipment. Measurement time was approximately 3 min per time point. The signal intensity from the DOSY experiment was used to measure protein concentration and the apparent self‐diffusion constant was converted into an average molecular weight and an estimated degree of hydrolysis. These values were plotted as a function of time and both the rate of solubilization and the rate of protein breakdown could be calculated. In addition to being rapid and noninvasive, DOSY using benchtop NMR spectroscopy has an advantage compared with other enzymatic hydrolysis characterization methods as it gives a direct measure of average protein size; many functional properties of proteins are strongly influenced by protein size. Therefore, a method to give protein concentration and average size in real time will allow operators to more tightly control production from enzymatic hydrolysis. Although only one type of material was tested, it is anticipated that the method should be applicable to a broad variety of enzymatic hydrolysis feedstocks. [ABSTRACT FROM AUTHOR]

Fragility is commonly quantified as the magnitude of change in viscosity at a temperature close to the glass transition temperature (Tg). It is a critical characteristic of melts used in scientific and industrial applications. The fragility of silicate melts generally increases with the depolymerization of silicate anions upon the addition of alkali or alkaline earth oxides. However, the effects of oxide additives on the fragility of aluminosilicate melts remain unclear. In this study, the effect of CaO or K2O addition on the viscosity of the 36CaO–51SiO2–13Al2O3 (mol.%) melt for the wide viscosity range of 10−1–1012 Pa s was studied. The relationship between the logarithmic viscosity and Tg‐scaled temperature indicated that the melt fragility increased with the addition of CaO, whereas the addition of K2O reduced the fragility when the additive content of CaO or K2O was less than 10.8 mol.%. The effect of the addition of K2O on fragility cannot be explained by the depolymerization of silicate anions alone. Raman and 27Al nuclear magnetic resonance spectroscopies of the glasses indicated that a decrease in the level of distortion of the AlO4 tetrahedra decreased the fragility of the aluminosilicate melt. [ABSTRACT FROM AUTHOR]

In this research, a new Ag(I) complex, namely, [Ag(5‐chloro‐1H‐benzimidazole)2(NO3)], has been synthesized using the benzimidazole‐based ligand 5‐chloro‐1H‐benzimidazole (5ClBZ). Ag(I) complexes were characterized by elemental analysis, UV‐Vis, FT‐IR, and 1H NMR spectroscopy, and DFT analysis was used. The free ligand and its Ag(I) complexes were tried for their biochemical properties, including antioxidant and antidiabetic properties. To study the molecular structures of the title compounds, in silico ADME/Tox research was performed on the newly made complex and free ligand. The empirical guidelines relating to ADME were utilized to conduct molecular docking simulations and in‐depth drug‐likeness profiling. This was carried out to validate the conclusions and identify exact binding interactions. Based on the study's findings, it has been determined that these new compounds have significant potential as powerful therapeutic agents for controlling antioxidant and antidiabetic activities. [ABSTRACT FROM AUTHOR]

In the present study, cellulose@SP@catechin@Fe3O4 nanocomposite underwent synthesis and characterization employing various analytical techniques, including Fourier transform‐infrared spectroscopy (FT‐IR), field‐emission scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller analysis, thermogravimetric analysis, vibrating sample magnetometry, X‐ray powder diffraction, and X‐ray spectroscopy. This reusable and efficient nanocomposite facilitated the synthesis of azo‐linked 4‐arylidene‐benzodiazepine, resulting in products with high yields. Characterization of these products was conducted utilizing 1H nuclear magnetic resonance (NMR), 13C NMR, and FT‐IR spectral data alongside mass analyses. Additionally, their antioxidant activities were assessed via 1,1‐diphenyl‐2‐picrylhydrazyl analysis. [ABSTRACT FROM AUTHOR]

Redox‐switchable catalysis is an efficient process to modulate the activity and/or selectivity in the polymerization with greater polymerization control and precision. In this work, the ferrocenyl‐functionalized diarylamines 4‐Fc‐C6H4NHC6H5 (HL1), 4‐Fc‐C6H4NH(2,6‐Me2C6H3) (HL2), and 2,6‐iPr2–4‐Fc‐C6H2NHC6H5 (HL3) were prepared and used as pro‐ligands to obtain the arylamido‐ligated rare‐earth metal complexes. Treatment of RE (CH2C6H4NMe2‐o)3 with 1 equiv. of HL1–3 in toluene afforded the ferrocenyl‐functionalized‐arylamido rare‐earth metal bis(o‐dimethylaminobenzyl) complexes L1Sc(CH2C6H4NMe2‐o)2 (1), L2RE(CH2C6H4NMe2‐o)2 (RE = Sc (2), Y (3)), and L3Y(CH2C6H4NMe2‐o)2 (4) in good yields. The compositions of these complexes were verified by NMR spectroscopy and elemental analysis. HL1 and HL3 were subjected to single‐crystal X‐ray diffraction. Electrochemical and NMR studies indicated that 4 could be oxidized with AgBF4 to generate the corresponding oxidized species 4ox, which could be facilely reduced back to 4 by use of CoCp2 as the reductant. The redox‐reversible ability between 4 and 4ox gave the chance to modulate the reactivity by switching the oxidized and reduced forms of one complex. For a controlled polymerization of ε‐caprolactone, 4 was active, and the polymerization process could be easily "on/off" switched by the redox reaction occurred on the ferrocenyl moiety. [ABSTRACT FROM AUTHOR]

Rational design of unnatural amino acid building blocks capable of stabilizing predictable secondary structures similar to protein fragments is pivotal for foldamer chemistry/catalysis. Here, we introduce novel β‐amino acid building blocks: [1S,2R,4R]exoCDA and [1S,2S,4R]endoCDA, derived from the abundantly available R(+)‐camphor, which is traditionally known for its medicinal value. Further, we demonstrate that the homooligomers of exoCDA adopt 6‐strand conformation, which switches to a robust 10/12‐helix simply by inserting flexible β‐hGly spacer at alternate positions (1 : 1 β‐hGly/exoCDA heterooligomers), as evident by DFT‐calculations, solution‐state NMR spectroscopy and X‐ray crystallography. To the best of our knowledge, this is the first example of crystalline‐state structure of left‐handed 10/12‐mixed helix, that is free from the conventional approach of employing β‐amino acids of either alternate chirality or alternate β2/β3 substitutions, to access the 10/12‐helix. The results also show that the homooligomers of heterochiral exoCDA don′t adopt helical fold, instead exhibit banana‐shaped strands, whereas the homodimers of the other diastereomer endoCDA, nucleate 8‐membered turns. Furthermore, the homo‐exoCDA and hetero‐[β‐hGly‐exoCDA] oligomers are found to exhibit self‐association properties with distinct morphological features. Overall, the results offer new possibilties of constructing discrete stable secondary and tertiary structures based on CDAs, which can accommodate flexible residues with desired side‐chain substitutions. [ABSTRACT FROM AUTHOR]

Hyperpolarization techniques provide a dramatic increase in sensitivity of nuclear magnetic resonance spectroscopy and imaging. In spite of the outstanding progress in solution‐state hyperpolarization of spin‐1/2 nuclei, hyperpolarization of quadrupolar nuclei remains challenging. Here, hyperpolarization of quadrupolar 14N nuclei with natural isotopic abundance of >99 % is demonstrated. This is achieved via pairwise addition of parahydrogen to tetraalkylammonium salts with vinyl or allyl unsaturated moieties followed by a subsequent polarization transfer from 1H to 14N nuclei at high magnetic field using PH‐INEPT or PH‐INEPT+ radiofrequency pulse sequence. Catalyst screening identified water‐soluble rhodium complex [Rh(P(m‐C6H4SO3Na)3)3Cl] as the most efficient catalyst for hyperpolarization of the substrates under study, providing up to 1.3 % and up to 6.6 % 1H polarization in the cases of vinyl and allyl precursors, respectively. The performance of PH‐INEPT and PH‐INEPT+ pulse sequences was optimized with respect to interpulse delays, and the resultant experimental dependences were in good agreement with simulations. As a result, 14N NMR signal enhancement of up to 760‐fold at 7.05 T (corresponding to 0.15 % 14N polarization) was obtained. [ABSTRACT FROM AUTHOR]

In‐situ NMR spectroscopy can provide valuable insight into chemical reactions, including detailed information on reaction kinetics and thus mechanism. The application of in‐situ NMR techniques to heterogeneous reactions has so far been limited by the requirement for efficient mixing, which is challenging within the confines of a standard NMR spectrometer. We report an automated plunger‐based device for the mixing of heterogeneous solid‐liquid reactions conducted within a 5 mm tube in a standard NMR probe, allowing reaction kinetics and speciation to be monitored in‐situ. The system has been tested by measuring the kinetics for three diverse reactions and comparison of these with the reaction velocities measured by routine ex‐situ analysis after sampling. The effect of key parameters including plunger design, plunger velocity, solid settling time, and mixing‐to‐acquisition time ratio are explored to determine the optimum parameters for combining efficient mixing with spectral quality. With adaptation, the device may also be suitable for benchtop NMR. [ABSTRACT FROM AUTHOR]

Hyperpolarization techniques provide a dramatic increase in sensitivity of nuclear magnetic resonance spectroscopy and imaging. In spite of the outstanding progress in solution‐state hyperpolarization of spin‐1/2 nuclei, hyperpolarization of quadrupolar nuclei remains challenging. Here, hyperpolarization of quadrupolar 14N nuclei with natural isotopic abundance of >99 % is demonstrated. This is achieved via pairwise addition of parahydrogen to tetraalkylammonium salts with vinyl or allyl unsaturated moieties followed by a subsequent polarization transfer from 1H to 14N nuclei at high magnetic field using PH‐INEPT or PH‐INEPT+ radiofrequency pulse sequence. Catalyst screening identified water‐soluble rhodium complex [Rh(P(m‐C6H4SO3Na)3)3Cl] as the most efficient catalyst for hyperpolarization of the substrates under study, providing up to 1.3 % and up to 6.6 % 1H polarization in the cases of vinyl and allyl precursors, respectively. The performance of PH‐INEPT and PH‐INEPT+ pulse sequences was optimized with respect to interpulse delays, and the resultant experimental dependences were in good agreement with simulations. As a result, 14N NMR signal enhancement of up to 760‐fold at 7.05 T (corresponding to 0.15 % 14N polarization) was obtained. [ABSTRACT FROM AUTHOR]

The field of coordination chemistry has evolved to intersect with organic chemistry and biochemistry, giving rise to the disciplines of organometallic and bioinorganic chemistry. Nuclear magnetic resonance (NMR) spectroscopy can be applied for characterizing transition metal complexes, spanning both diamagnetic and paramagnetic complexes prevalent in organometallic compounds and metalloproteins. This review offers a comprehensive overview of a wide variety of characterization techniques, ranging from basic 1H and 13C NMR spectroscopy to advanced methods such as heteronuclear experiments, polarization transfer techniques, relaxometry, and multidimensional NMR spectroscopy. The diverse array of NMR spectroscopic methods outlined here promises to enhance our comprehension of transition metal complexes, facilitating the development of innovative catalysts and therapeutics. [ABSTRACT FROM AUTHOR]

A novel class of diazonium salts is introduced for the photochemical aryl‐aryl coupling to produce (substituted) biphenyls. As common diazonium tetrafluoroborate salts fail, soluble and safe aryl diazonium trifluoroacetates are applied. In this mild synthesis route no catalysts are required to generate an aryl‐radical by irradiation with UV‐A light (365 nm). This reactive species undergoes direct C−H arylation at an arene, forming the product in reasonable reaction times. With the implementation of a continuous flow setup in a capillary photoreactor 13 different biphenyl derivatives are successfully synthesized. By integrating an inline 19F‐NMR benchtop spectrometer, samples are reliably quantified as the fluorine‐substituents act as a probe. Here, real‐time NMR spectroscopy is a perfect tool to monitor the continuously operated system, which produces fine chemicals of industrial relevance even in a multigram scale. [ABSTRACT FROM AUTHOR]

In this work, two new biscyclometalated Ir(III) complexes with diimine ligands were synthesized. The compounds were characterized by 1D and 2D NMR spectroscopy and HR ESI mass spectrometry. All complexes exhibit efficient phosphorescence with pronounced sensitivity to the presence of oxygen. The photophysical properties of the obtained compounds, including absorption, emission spectra, lifetimes and quantum yields of phosphorescence were measured in various aqueous and model biological media with variations in pH, temperature and at various O2 concentrations. The complexes exhibit a very good sensory response to the changes in oxygen concentration, resulting in an increase in quantum yields and lifetimes by 2.8–5.5 times upon oxygen removal from aerated aqueous solutions. Biological tests with CHO‐K1 cell line have shown that these compounds display low toxicity, rapid internalization into cells and localization predominantly in lysosomes. For the most promising complex the phosphorescence lifetime imaging experiments were conducted, revealing that this sensor markedly changes the phosphorescence lifetime values in cells from 1.8 to 4.1 μs upon transition from normoxia to simulated hypoxia. The obtained results indicate that this type of iridium chromophores can be effectively used for assessing the oxygen status of living objects by using time‐resolved luminescent microscopy. [ABSTRACT FROM AUTHOR]

The homogeneously catalyzed Guerbet upgrading of ethanol to butanol can be modulated by the application of partial H2 pressure before the reaction. Ruthenium(II) PNP pincer complexes with methylene‐extended acridine‐based ligands and singly‐chelated ruthenium(II) complexes with PN ligands perform best at very low catalyst loadings and upon the application of catalyst‐specific pre‐reaction partial H2 pressure. The combination of ruthenium(II) PNP pincer complexes and manganese(I) pincer complexes with MACHO‐type PNP ligands allows for even lower ruthenium loadings while retaining low base load and consumption, thus enabling high space‐time yields, catalyst productivity and recyclability. Mechanistically, Mn is proposed to stabilize coordinatively unsaturated Ru species and allow coordination of ethoxide to Ru instead of attacking the electrophilic ligand backbone based on NMR spectroscopy and X‐ray crystallography. [ABSTRACT FROM AUTHOR]

In order to explore more sustainable epoxy resins, a series of novel bio‐based epoxy resins with long silicone‐chain are synthesized from honokiol. First, honokiol epoxy (HOEP) is synthesized from honokiol. Then, the hydrogen‐containing siloxane (HS) is copolymerized with honokiol epoxy, and the bio‐based epoxy resins with long silicone‐chain are prepared through the hydrosilylation reaction. Before curing with methyl hexahydrophthalic anhydride (MHHPA), the structure of silicone honokiol epoxy (SIHOEP) is confirmed by Fourier‐transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H NMR). The molecular weight of SIHOEP is analyzed by gel permeation chromatography (GPC). The results show that the toughness of SIHOEP‐MHHPA is enhanced after curing, the maximum elongation at break reached 45.75%, and the glass transition temperature (Tg) is up to 92.9 °C. Long silicone‐chain segment can enhance the toughness of bio‐based epoxy. By adjusting the hydrogen content of long‐chain hydrogen‐containing siloxane and the reaction ratio, the overall performance of bio‐based epoxy silicone resins can be effectively controlled, which provides a valuable guide for the design of bio‐based epoxy materials with excellent mechanical properties. Meanwhile, the curing kinetics of bio‐based silicone/epoxy hybrid resins with methyl hexahydrophthalic anhydride (MHHPA) as curing agent is studied. [ABSTRACT FROM AUTHOR]

Summary: Iron (Fe) is crucial for metabolic functions of living organisms. Plants access occluded Fe through interactions with rhizosphere microorganisms and symbionts. Yet, the interplay between Fe addition and plant–mycorrhizal interactions, especially the molecular mechanisms underlying mycorrhiza‐assisted Fe processing in plants, remains largely unexplored.We conducted mesocosms in Pinus plants inoculated with different ectomycorrhizal fungi (EMF) Suillus species under conditions with and without Fe coatings. Meta‐transcriptomic, biogeochemical, and X‐ray fluorescence imaging analyses were applied to investigate early‐stage mycorrhizal roots.While Fe addition promoted Pinus growth, it concurrently reduced mycorrhiza formation rate, symbiosis‐related metabolites in plant roots, and aboveground plant carbon and macronutrient content. This suggested potential trade‐offs between Fe‐enhanced plant growth and symbiotic performance. However, the extent of this trade‐off may depend on interactions between host plants and EMF species. Interestingly, dual EMF species were more effective at facilitating plant Fe uptake by inducing diverse Fe‐related functions than single‐EMF species. This subsequently triggered various Fe‐dependent physiological and biochemical processes in Pinus roots, significantly contributing to Pinus growth. However, this resulted in a greater carbon allocation to roots, relatively reducing the aboveground plant carbon content.Our study offers critical insights into how EMF communities rebalance benefits of Fe‐induced effects on symbiotic partners. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Eight new guaiane‐type sesquiterpenoid trimers, artemsieverolactones A—H, possessing unprecedented scaffolds via biocatalyzed [4+2] Diels−Alder cycloaddition reactions were identified from Artemisia sieversiana. Their structures were determined by comprehensive spectroscopic data, single‐crystal X‐ray diffraction analyses, and ECD calculations. In terms of structure, artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane‐type sesquiterpenoid through four different [4+2] Diels−Alder cycloaddition models. Antihepatic fibrosis assay suggested that five compounds exhibited activity against HSC‐LX2 with IC50 values ranging from 37.8 to 117.1 μmol/L. The most active artemsieverolactone B (2) displayed significant inhibitory activity against HSC‐LX2 with IC50 value of 37.8 μmol/L, which was 3 times more active than the positive drug silybin (IC50, 139.7 μmol/L). Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen type I (Col I), human hyaluronic acid (HA), and human laminin (HL) with IC50 values of 40.4 μmol/L (Col I), 55.1 μmol/L (HL), 47.3 μmol/L (HA), which was 2 to 3‐fold more potent than silybin. [ABSTRACT FROM AUTHOR]

7Li nuclear magnetic resonance (NMR) spectroscopy is an ideal tool to study hierarchically assembled helicates of the form Li[Li3L6Ti2]. Internally bound and external lithium ions can be well distinguished by solution‐ or solid‐state NMR spectroscopy and dimerization constants of the monomer/dimer equilibrium can be easily determined in solution. Averaged dimerization constants can be estimated in case of statistical mixtures of helicates formed from mixtures of ligands. [ABSTRACT FROM AUTHOR]

Molecules with nonplanar architectures are highly desirable due to their unique topological structures and functions. We report here the synthesis of two molecular containers (1 ⋅ 3Br− and 1 ⋅ 3Cl−), which utilize intramolecular cation‐π interactions to enforce macrocylic arrangements and exhibit high binding affinity and luminescent properties. Remarkably, the geometry of the cation‐π interaction can be flexibly tailored to achieve a precise ring arrangement, irrespective of the angle of the noncovalent bonds. Additionally, the C−H⋅⋅⋅Br− hydrogen bonds within the container are also conducive to stabilizing the bowl‐shaped conformation. These bowl‐shaped conformations were confirmed both in solution through NMR spectroscopy and in the solid state by X‐ray studies. 1 ⋅ 3Br− shows high binding affinity and selectivity: F−>Cl−, through C−H⋅⋅⋅X− (X=F, Cl) hydrogen bonds. Additionally, these containers exhibited blue fluorescence in solution and yellow room‐temperature phosphorescence (RTP) in the solid state. Our findings illustrate the utility of cation‐π interactions in designing functional molecules. [ABSTRACT FROM AUTHOR]

Molecules with nonplanar architectures are highly desirable due to their unique topological structures and functions. We report here the synthesis of two molecular containers (1 ⋅ 3Br− and 1 ⋅ 3Cl−), which utilize intramolecular cation‐π interactions to enforce macrocylic arrangements and exhibit high binding affinity and luminescent properties. Remarkably, the geometry of the cation‐π interaction can be flexibly tailored to achieve a precise ring arrangement, irrespective of the angle of the noncovalent bonds. Additionally, the C−H⋅⋅⋅Br− hydrogen bonds within the container are also conducive to stabilizing the bowl‐shaped conformation. These bowl‐shaped conformations were confirmed both in solution through NMR spectroscopy and in the solid state by X‐ray studies. 1 ⋅ 3Br− shows high binding affinity and selectivity: F−>Cl−, through C−H⋅⋅⋅X− (X=F, Cl) hydrogen bonds. Additionally, these containers exhibited blue fluorescence in solution and yellow room‐temperature phosphorescence (RTP) in the solid state. Our findings illustrate the utility of cation‐π interactions in designing functional molecules. [ABSTRACT FROM AUTHOR]

A novel and efficient procedure has been developed to synthesize furan‐2‐carboxylate derivatives through a one‐pot condensation of chloroacetate derivatives, 1,3‐diketones, and chloroform in the presence of magnetic sodium aluminate 40 wt. % (Aluminate NP‐40). The synthesized heterogeneous catalyst can be easily recovered from the reaction mixture by applying an external magnetic field. Magnetic aluminate NP catalysts provide a sustainable, environmentally friendly, and cost‐effective method for synthesizing furan‐2‐carboxylate derivatives. Additionally, the catalyst is stable and can be reused multiple times without losing its catalytic properties. High product yields in a short experimental time and easy workup are other advantages of the present method. All synthesized compounds were characterized by NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Existing modelling tools, developed to aid the design of efficient molecular wires and to better understand their charge‐transport behaviour and mechanism, have limitations in accuracy and computational cost. Further research is required to develop faster and more precise methods that can yield information on how charge transport properties are impacted by changes in the chemical structure of a molecular wire. In this study, we report a clear semilogarithmic correlation between charge transport efficiency and nuclear magnetic resonance chemical shifts in multiple series of molecular wires, also accounting for the presence of chemical substituents. The NMR data was used to inform a simple tight‐binding model that accurately captures the experimental single‐molecule conductance values, especially useful in this case as more sophisticated density functional theory calculations fail due to inherent limitations. Our study demonstrates the potential of NMR spectroscopy as a valuable tool for characterising, rationalising, and gaining additional insights on the charge transport properties of single‐molecule junctions. [ABSTRACT FROM AUTHOR]

We report on the synthesis and characterization of a series of (mostly) air‐stable diorganyl bis(pyridylimino) isoindolide (BPI) aluminum complexes and their chemistry upon visible‐light excitation. The redox non‐innocent BPI pincer ligand allows for efficient charge transfer homolytic processes of the title compounds. This makes them a universal platform for the generation of carbon‐centered radicals. The photo‐induced homolytic cleavage of the Al−C bonds was investigated by means of stationary and transient UV/Vis spectroscopy, spin trapping experiments, as well as EPR and NMR spectroscopy. The experimental findings were supported by quantum chemical calculations. Reactivity studies enabled the utilization of the aluminum complexes as reactants in tin‐free Giese‐type reactions and carbonyl alkylations under ambient conditions, which both indicated radical‐polar crossover behavior. A deeper understanding of the physical fundamentals and photochemical process was provided, furnishing in turn a new strategy to control the reactivity of bench‐stable aluminum organometallics. [ABSTRACT FROM AUTHOR]

Existing modelling tools, developed to aid the design of efficient molecular wires and to better understand their charge‐transport behaviour and mechanism, have limitations in accuracy and computational cost. Further research is required to develop faster and more precise methods that can yield information on how charge transport properties are impacted by changes in the chemical structure of a molecular wire. In this study, we report a clear semilogarithmic correlation between charge transport efficiency and nuclear magnetic resonance chemical shifts in multiple series of molecular wires, also accounting for the presence of chemical substituents. The NMR data was used to inform a simple tight‐binding model that accurately captures the experimental single‐molecule conductance values, especially useful in this case as more sophisticated density functional theory calculations fail due to inherent limitations. Our study demonstrates the potential of NMR spectroscopy as a valuable tool for characterising, rationalising, and gaining additional insights on the charge transport properties of single‐molecule junctions. [ABSTRACT FROM AUTHOR]

The salt metathesis reaction of dipotassium germacyclopentadienediide with aluminum(III) dichlorides provides either half‐sandwich alumole complexes of germanium(II) or aluminylene germole complexes. Their molecular structure and the delocalized bonding situation, revealed by density functional theory (DFT) calculations, are equally described as isomeric aluminagerma[5]pyramidanes with either the germanium or the aluminum atom in the apical position of the pentagonal pyramid. The product formation and the selectivity of the reaction depends on the third substituent of the aluminum dichloride. Aryl‐substituents favor the formation of alumole complexes and Cp*‐substituents that of the isomeric germole complexes. With amino‐substituents at the aluminum atom mixtures of both isomers are formed and the positional exchange of the two heteroatoms is shown by NMR spectroscopy. The alumole complexes of germanium(II) undergo facile reductive elimination of germanium and form the corresponding alumoles. [ABSTRACT FROM AUTHOR]

Benchtop NMR spectroscopy is attractive for process monitoring; however, there are still drawbacks that often hamper its use, namely, the comparatively low spectral resolution in 1H NMR, as well as the low signal intensities and problems with the premagnetization of flowing samples in 13C NMR. We show here that all these problems can be overcome by using 1H‐13C polarization transfer methods. Two ternary test mixtures (one with overlapping peaks in the 1H NMR spectrum and one with well‐separated peaks, which was used as a reference) were studied with a 1 T benchtop NMR spectrometer using the polarization transfer sequence PENDANT (polarization enhancement that is nurtured during attached nucleus testing). The mixtures were analyzed quantitatively in stationary as well as in flow experiments by PENDANT enhanced 13C NMR experiments, and the results were compared with those from the gravimetric sample preparation and from standard 1H and 13C NMR spectroscopy. Furthermore, as a proxy for a process monitoring application, continuous dilution experiments were carried out, and the composition of the mixture was monitored in a flow setup by 13C NMR benchtop spectroscopy with PENDANT. The results demonstrate the high potential of polarization transfer methods for applications in quantitative process analysis with benchtop NMR instruments, in particular with flowing samples. [ABSTRACT FROM AUTHOR]

Efficient and robust analytical methods are needed to improve the identification and subsequent regulation of new psychoactive substances (NPS). NMR spectroscopy is a unique method able to determine the structure of small molecules such as NPS even in mixtures. However, high‐field NMR analysis is associated with expensive purchase and maintenance costs. For more than a decade, compact NMR spectrometers have changed this paradigm. It was recently shown that a dedicated analytical workflow combining compact NMR and databases could identify the molecular structure of NPS, in spite of the lower spectral dispersion and sensitivity of compact spectrometers. This approach relies on 1H‐13C HSQC to both recognize NPS and elucidate the structure of unknown substances. Still, its performance is limited by the need to compromise between resolution and experiment time. Here, we show that this strategy can be significantly improved by implementing non‐uniform sampling (NUS) to improve spectral resolution in the 13C dimension of HSQC at no cost in terms of experiment time. Gains in the range of 3 to 4 in resolution are achieved for pure NPS and for a mixture. Finally, 2D HSQC with NUS was applied to improve the identification of NPS with the assistance of databases. The resulting method appears as a useful tool for the characterization of NPS in mixtures, which is essential for forensic laboratories. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) is an established method to determine self‐diffusion coefficients in liquids with high precision. The development of benchtop NMR spectrometers makes the method accessible to a wider community. In most cases, 1H NMR spectroscopy is used to determine self‐diffusion coefficients due to its high sensitivity. However, especially when using benchtop NMR spectrometers for the investigation of complex mixtures, the signals in 1H NMR spectra can overlap, hindering the precise determination of self‐diffusion coefficients. In 13C NMR spectroscopy, the signals of different compounds are generally well resolved. However, the sensitivity of 13C NMR is significantly lower than that of 1H NMR spectroscopy leading to very long measurement times, which makes diffusion coefficient measurements based on 13C NMR practically infeasible with benchtop NMR spectrometers. To circumvent this problem, we have combined two known pulse sequences, one for polarization transfer from 1H to the 13C nuclei (PENDANT) and one for the measurement of diffusion coefficients (PFG). The new method (PENPFG) was used to measure the self‐diffusion coefficients of three pure solvents (acetonitrile, ethanol and 1‐propanol) as well as in all their binary mixtures and the ternary mixture at various compositions. For comparison, also measurements of the same systems were carried out with a standard PFG‐NMR routine on a high‐field NMR instrument. The results are in good agreement and show that PENPFG is a useful tool for the measurement of the absolute value of the self‐diffusion coefficients in complex liquid mixtures with benchtop NMR spectrometers. [ABSTRACT FROM AUTHOR]

Understanding environmental change is challenging and requires molecular‐level tools to explain the physicochemical phenomena behind complex processes. Nuclear magnetic resonance (NMR) spectroscopy is a key tool that provides information on both molecular structures and interactions but is underutilized in environmental research because standard "high‐field" NMR is financially and physically inaccessible for many and can be overwhelming to those outside of disciplines that routinely use NMR. "Low‐field" NMR is an accessible alternative but has reduced sensitivity and increased spectral overlap, which is especially problematic for natural, heterogeneous samples. Therefore, the goal of this study is to investigate and apply innovative experiments that could minimize these challenges and improve low‐field NMR analysis of environmental and biological samples. Spectral simplification (JRES, PSYCHE, singlet‐only, multiple quantum filters), selective detection (GEMSTONE, DREAMTIME), and heteronuclear (reverse and CH3/CH2/CH‐only HSQCs) NMR experiments are tested on samples of increasing complexity (amino acids, spruce resin, and intact water fleas) at‐high field (500 MHz) and at low‐field (80 MHz). A novel experiment called Doubly Selective HSQC is also introduced, wherein 1H signals are selectively detected based on the 1H and 13C chemical shifts of 1H–13C J‐coupled pairs. The most promising approaches identified are the selective techniques (namely for monitoring), and the reverse and CH3‐only HSQCs. Findings ultimately demonstrate that low‐field NMR holds great potential for biological and environmental research. The multitude of NMR experiments available makes NMR tailorable to nearly any research need, and low‐field NMR is therefore anticipated to become a valuable and widely used analytical tool moving forward. [ABSTRACT FROM AUTHOR]

Virus‐glycan interactions play a crucial role in the infection process of many viruses. NMR spectroscopy has emerged as a powerful tool for studying these interactions at the molecular level. In this article, we review several published papers and reports that have highlighted the application of NMR spectroscopy in understanding the complex questions of how viruses engage with and bind to receptor glycans. The use of saturation transfer difference (STD) NMR spectroscopy has demonstrated itself as highly advantageous in investigating the interaction between glycans and intact virions or virus‐like particles (VLPs). The broad NMR signal linewidth of virions and VLPs allows efficient saturation without affecting the glycan signals. The advantage of this approach is that the viral capsid environment in protein organization and function is not ignored and therefore provides a more biologically relevant model for exploring the interactions between the virus and the host cell glycans. We will review some examples of using NMR spectroscopy to study influenza cell tropism, rotaviruses, and noroviruses. [ABSTRACT FROM AUTHOR]

Background: X‐linked dystonia‐parkinsonism (XDP) is a rare movement disorder characterized by profound neurodegeneration in the basal ganglia. The molecular consequences and the bioenergetic state of affected individuals remain largely unexplored. Objectives: To investigate the bioenergetic state in male patients with XDP and female carriers using 31phosphorus magnetic resonance spectroscopy imaging and to correlate these findings with clinical manifestations. Methods: We examined the levels of high‐energy phosphorus‐containing metabolites (HEP) in the basal ganglia and cerebellum of five male patients with XDP, 10 asymptomatic female heterozygous carriers, and 10 SVA‐insertion‐free controls. Results: HEP levels were reduced in the basal ganglia of patients with XDP (PwXDP) compared to controls, but increased in the cerebellum of both male patients and female carriers. Conclusions: Our findings suggest a potential compensatory mechanism in the cerebellum of female carriers regardless of sex. Our study highlights alterations in HEP levels in PwXDP patients and female carriers. [ABSTRACT FROM AUTHOR]

There is a need to develop therapies for neonatal encephalopathy (NE) in low‐ and middle‐income countries (LMICs) where the burden of disease is greatest and therapeutic hypothermia (HT) is not effective. We aimed to assess the efficacy of melatonin following inflammation‐amplified hypoxia–ischaemia (IA‐HI) in the newborn piglet. The IA‐HI model accounts for the contribution of infection/inflammation in this setting and HT is not cytoprotective. We hypothesised that intravenous melatonin (5% ethanol, at 20 mg/kg over 2 h at 1 h after HI + 10 mg/kg/12 h between 24 and 60 h) is safe and associated with: (i) reduction in magnetic resonance spectroscopy lactate/N‐acetylaspartate (MRS Lac/sNAA); (ii) preservation of phosphorus MRS phosphocreatine/phosphate exchange pool (PCr/Epp); (iii) improved aEEG/EEG recovery and (iv) cytoprotection on immunohistochemistry. Male and female piglets underwent IA‐HI by carotid artery occlusion and reduction in FiO2 to 6% at 4 h into Escherichia coli lipopolysaccharide sensitisation (2 μg/kg bolus + 1 μg/kg/h over 12 h). At 1 h after IA‐HI, piglets were randomised to HI‐saline (n = 12) or melatonin (n = 11). There were no differences in insult severity between groups. Target melatonin levels (15–30 mg/L) were achieved within 3 h and blood ethanol levels were <0.25 g/L. At 60 h, compared to HI‐saline, melatonin was associated with a reduction of 0.197 log10 units (95% CrI [−0.366, −0.028], Pr(sup) 98.8%) in basal‐ganglia and thalamic Lac/NAA, and 0.257 (95% CrI [−0.676, 0.164], Pr(sup) 89.3%) in white matter Lac/NAA. PCr/Epp was higher in melatonin versus HI‐saline (Pr(sup) 97.6%). Melatonin was associated with earlier aEEG/EEG recovery from 19 to 24 h (Pr(sup) 95.4%). Compared to HI‐saline, melatonin was associated with increased NeuN+ cell density (Pr(sup) 99.3%) across five of eight regions and reduction in TUNEL‐positive cell death (Pr(sup) 89.7%). This study supports the translation of melatonin to early‐phase clinical trials. Melatonin is protective following IA‐HI where HT is not effective. These data guide the design of future dose‐escalation studies in the next phase of the translational pipeline. [ABSTRACT FROM AUTHOR]

Helicobacter pylori and Epstein–Barr Virus (EBV) are Group 1 carcinogens that can enhance gastric cancer progression. Bioactive substances extracted from plants can be effective therapeutic agents in cancer treatment. For example, Withania somnifera extract‐WSE reduces the Gankyrin oncoprotein, which is upregulated in the presence of H. pylori and EBV. The various biochemical and metabolic changes upon 24 hrs post‐infection followed by W. somnifera extract (WSE) treatment on gastric epithelial cells (AGS) can be studied using spectroscopic techniques. In the biomedical sciences, Raman and NMR spectroscopy have been extensively employed to interpret cellular alterations contributing to the onset of infection and the severity of gastric cancer. More specifically, alterations in cellular biochemical homeostasis are linked to the moieties of cholesterol, collagen, choline, carbohydrate, lipids, tyrosine, and phenylalanine. Further, we have found significantly elevated FWHM for carbohydrates, tumor associated protein, collagen, cholesterol, and cholesterol ester in the co‐infection model. We also looked into the potential correlation between these molecules using molecular network analysis and found several related factors that can be modulated through biomolecular levels. These molecules are crucial in several physiological functions, including cell division, cell proliferation, apoptosis, necrosis, cell migration, and lipid transport. Our study paves the pathway to study H. pylori and EBV co‐infection in human gastric epithelial cells and the therapeutic interventions of WSE in this scenario and highlights specific biomolecular alterations, which can be focused for further mechanistic investigations. [ABSTRACT FROM AUTHOR]

This research introduces an eco‐friendly and innovative technique for efficiently producing p‐tolylmethanol derivatives 4(a–k) using electro‐organic synthesis based on the Grignard reaction. By employing electrochemical methods, this approach offers several advantages, including enhanced reaction efficiency and reduced environmental impact. The process involves the electrochemical generation of the Grignard reagent, followed by its reaction with appropriate substrates to yield the desired p‐tolylmethanol derivatives. Our team optimized various reaction parameters like choice of solvent, electrode material, and reaction conditions to achieve high yields and selectivity. The developed electro‐organic method demonstrated outstanding efficiency and presents a fresh and environmentally conscious approach to synthesizing p‐tolylmethanol derivatives from benzaldehyde 1(a–e) and bromobenzene 2(a–h) via the Grignard reaction, yielding excellent results (85–93%). The resulting compounds were comprehensively characterized using melting point, 1H NMR spectroscopy, and CHN analysis to verify their structures. This electro‐organic approach holds significant potential as a sustainable strategy for synthesizing valuable organic compounds. [ABSTRACT FROM AUTHOR]

The current study explains the degradation behavior of Febuxostat API, a non‐purine xanthine oxidase inhibitor used to treat hyperuricemia. A degradation study was carried out as per the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines, and the study confirms that the Febuxostat is largely stable in thermal, photolytic, oxidative, and basic hydrolytic conditions and labile in acid hydrolysis conditions. There were four different degradation products (DPs) found during acid hydrolysis; of these, DPs 2, 3, and 4 are new and have never been reported before, while DP 1 is known and has already been published. All these DPs were identified using ultra‐high‐performance liquid chromatography‐mass spectrometry (UHPLC‐MS) analysis, purified by using preparative HPLC, and characterized using high‐resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy techniques. The formed DPs are by the hydrolysis of the cyano functional group of Febuxostat and the esterification of DP‐1 under acidic conditions. All DP's structural characterization was carried out using NMR spectroscopy and HRMS. The present study describes concrete confirmation of DP structures and it explains the stability behavior of the Febuxostat. The current method is also used to identify DPs with shorter runtime in the future. [ABSTRACT FROM AUTHOR]