is a medicinal plant used for the treatment of malaria, toothache, and stomach problems. The root parts of the plant are also used for healing liver disorders. Silica gel chromatography separation of CHCl/MeOH (1:1) and MeOH extracts of roots of result in the isolation of three compounds, namely, bergenin (), -sitosterol (), and epigallocatechin 3-gallate (), reported herein for the first time from the plant.
View Article and Find Full Text PDFEngl. plant is traditionally used in Ethiopia to treat various diseases. However, the biological and phytochemical properties of the leaves are not well documented.
View Article and Find Full Text PDFFunctional silanes are multifaceted cross-linkers, compatibilizers, coupling agents, and surface modifiers. Herein, we present organofunctional polysiloxane building blocks that offer great versatility in terms of molecular weight, degree of condensation, and the choice and loading of organic substituent groups. The organofunctional polyethoxysilanes (funPEOS) are prepared in a one-pot, two-step process: synthesis of the PEOS carrier/substrate, followed by grafting a functional silane "shell", both based on condensation with acetic anhydride.
View Article and Find Full Text PDFis a therapeutic plant traditionally used to treat rabies, snake bite, diarrhea, and wound healing. To address the bioactive compounds exhibiting these activities, we performed a comprehensive study on the roots of the plant. Thus, the present study aims to inspect the antioxidant and antibacterial efficacies of compounds isolated from the combined dichloromethane : methanol (1 : 1) and methanol extracts of along with the study of their interaction with selected protein targets.
View Article and Find Full Text PDFThermal stability of solid electrolytes and their compatibility with battery electrodes are key factors to ensure stable cycling and high operational safety of all-solid-state batteries. Here, we study the compatibility of a hydroborate solid electrolyte Na(BH)(BH) with 3 V-class cathode active materials: NaCrO, NaMnO, and NaFeO. Among these layered sodium transition metal oxide cathodes, NaCrO shows the highest thermal compatibility in contact with the hydroborate solid electrolyte up to 525 °C in the discharged state.
View Article and Find Full Text PDFUreido-functionalized compounds play an indispensable role in important biochemical processes, as well as chemical synthesis and production. Isocyanates, and KOCN in particular, are the preferred reagents for the ureido functionalization of amine-bearing compounds. In this study, we evaluate the potential of urea as a reagent to graft ureido groups onto amines at relatively low temperatures (<100 °C) in aqueous media.
View Article and Find Full Text PDFShortwave infrared (SWIR) optical sensing and imaging are essential to an increasing number of next-generation applications in communications, process control or medical imaging. An all-organic SWIR upconversion device (OUC) consists of an organic SWIR sensitive photodetector (PD) and an organic light-emitting diode (OLED), connected in series. OUCs directly convert SWIR to visible photons, which potentially provides a low-cost alternative to the current inorganic compound-based SWIR imaging technology.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
June 2021
Water-in-salt electrolytes have successfully expanded the electrochemical stability window of aqueous electrolytes beyond 2 V. Further improvements in stability can be achieved by partially substituting water with either classical organic solvents or ionic liquids. Here, we study ternary electrolytes composed of LiTFSI, water, and imidazolium ionic liquids.
View Article and Find Full Text PDFSupported ruthenium was used in the liquid phase catalytic transfer hydrogenation of furfural. To improve the stability of Ru against leaching, phosphorous was introduced on a Ru/AlO based catalyst upon impregnation with ammonium hypophosphite followed by either reduction or calcination to study the effect of phosphorous on the physico-chemical properties of the active phase. Characterization using X-ray diffraction, solid state P nuclear magnetic resonance spectroscopy, X-ray absorption spectroscopy, temperature programmed reduction with H, infrared spectroscopy of pyridine adsorption from the liquid phase and transmission electron microscopy indicated that phosphorous induces a high dispersion of Ru, promotes Ru reducibility and is responsible for the formation of acid species of Brønsted character.
View Article and Find Full Text PDFBiotransformation plays a crucial role in regulating the bioaccumulation potential and toxicity of organic compounds in organisms but is, in general, poorly understood for emerging contaminants. Here, we have used diclofenac as a model compound to study the impact of biotransformation on the bioaccumulation potential and toxicity in two keystone aquatic invertebrates: and . In both species, diclofenac was transformed into several oxidation products and conjugates, including two novel products, that is, diclofenac taurine conjugate (DCF-M403) and unexpected diclofenac methyl ester (DCF-M310.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2020
Design and synthesis of nanostructured responsive gels have attracted increasing attention, particularly in the biomedical domain. Polymer chain configurations and nanodomain sizes within the network can be used to steer their functions as drug carriers. Here, a catalyst-free facile one-step synthesis strategy is reported for the design of pH-responsive gels and controlled structures in nanoscale.
View Article and Find Full Text PDFIn this article, we report the synthesis of 2,4,6-substituted -triazine-based organophosphorus compounds via a two-step process, which enables their production in high yields, and with a high purity as solids. In the first step, a Michaelis-Arbuzov rearrangement of cyanuric chloride with triethyl phosphite afforded 2,4,6-trisdiethoxyphosphinyl-1,3,5-triazine (HEPT). Subsequently, the nucleophilic substitution reaction on the triazine carbon was achieved, owing to the electron-withdrawing ability of the phosphonate groups.
View Article and Find Full Text PDFAspartimide (Asi) formation is a notorious side reaction in peptide synthesis that is well characterized and described in literature. In this context, we observed significant amounts of chain termination in Fmoc-SPPS while synthesizing the N-terminal Xaa-Asp-Yaa motif. This termination was caused by the formation of piperazine-2,5-diones.
View Article and Find Full Text PDFThe role of various additives (emulsifier, anti-dripping agent) and formulation procedures (pre-dispersion of solid additives in polyol via milling) which influence the flame retardancy of 6,6'-[ethan-1,2-diylbis(azandiyl)]bis(6H-dibenzo[c,e][1,2]oxaphosphin-6-oxid) (EDA-DOPO) containing flexible polyurethane foams has been investigated in this work. For comparison, the flame retardancy of two additional structurally-analogous bridged 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based compounds, i.e.
View Article and Find Full Text PDFSynthesis of intermediate containing P()-Cl bonds is the key to converting P()-H bonds to P()-N. In this work we have performed chlorination reactions of different -phosphinates and -phosphonates using -chlorosuccinimide as an environmentally-benign chlorinating agent. The chlorination reaction showed high yield and high selectivity for transformation of P()-H bonds into P()-Cl analogues, resulting in an easily separable succinimide as the by-product.
View Article and Find Full Text PDFCoordination complexes of magnesium borohydride show promising properties as solid electrolytes for magnesium ion batteries and warrant a thorough microscopic description of factors governing their mobility properties. Here, the dynamics of Mg(BH)-diglyme on the atomic level are investigated by means of quasielastic neutron scattering supported by density functional theory calculations and IR and NMR spectroscopy. Employing deuterium labeling, we can unambiguously separate all the hydrogen-containing electrolyte components, which facilitate Mg transport, and provide a detailed analytical description of their motions on the picosecond time scale.
View Article and Find Full Text PDFStereochemical effects during two-dimensional crystallization of bisheptahelicene diastereomers on a Cu(111) surface have been studied with scanning tunnelling microscopy. The (M,M)- and (P,P)-enantiomers crystallize into a monolayer racemate lattice, whereas the (M,P)-diastereomers aggregate into their own monolayer phase.
View Article and Find Full Text PDFTransient activation of biochemical reactions by visible light and subsequent return to the inactive state in the absence of light is an essential feature of the biochemical processes in photoreceptor cells. To mimic such light-responsiveness with artificial nanosystems, polymersome nanoreactors were developed that can be switched on by visible light and self-revert fast in the dark at room temperature to their inactive state. Donor-acceptor Stenhouse adducts (DASAs), with their ability to isomerize upon irradiation with visible light, were employed to change the permeability of polymersome membranes by switching polarity from a nonpolar triene-enol form to a cyclopentenone with increased polarity.
View Article and Find Full Text PDFHybrid perovskite crystals with organic and inorganic structural components are able to combine desirable properties from both classes of materials. Electronic interactions between the anionic inorganic framework and functional organic cations (such as chromophores or semiconductors) can give rise to unusual photophysical properties. Cyanine dyes are a well known class of cationic organic dyes with high extinction coefficients and tunable absorption maxima all over the visible and near-infrared spectrum.
View Article and Find Full Text PDFLignin is the most abundant aromatic biopolymer, functioning as an integral component of woody materials. In its unmodified form it shows limited water solubility and is relatively unreactive, so biotechnological lignin valorisation for high-performance applications is greatly underexploited. Lignin can be obtained from the pulp and paper industry as a by-product.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
February 2018
Cellulose nanocrystals (CNCs) with >2000 photoactive groups on each can act as highly efficient initiators for radical polymerizations, cross-linkers, as well as covalently embedded nanofillers for nanocomposite hydrogels. This is achieved by a simple and reliable method for surface modification of CNCs with a photoactive bis(acyl)phosphane oxide derivative. Shape-persistent and free-standing 3D structured objects were printed with a mono-functional methacrylate, showing a superior swelling capacity and improved mechanical properties.
View Article and Find Full Text PDFPinoresinol is a dimer of two β-β'-linked coniferyl alcohol molecules. It is both a plant defense molecule synthesized through the shikimic acid pathway and a representative of several β-β-linked dimers produced during the microbial degradation of lignin in dead plant material. Until now, little has been known about the bacterial catabolism of such dimers.
View Article and Find Full Text PDFIndole or indazole-based synthetic cannabinoids (SCs) bearing substituents derived from valine or tert-leucine are frequently abused new psychoactive substances (NPS). The emergence of 5F-MDMB-PICA (methyl N-{[1-(5-fluoropentyl)-1H-indol-3-yl]carbonyl}-3-methylvalinate) on the German drug market is a further example of a substance synthesized in the context of scientific research being misused by clandestine laboratories by adding it to 'legal high' products. In this work, we present the detection of 5F-MDMB-PICA in several legal high products by gas chromatography-mass spectrometry (GC-MS) analysis.
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