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Search for "polymer" in Full Text gives 607 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors
Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14
- through either (i) the cationic nature of the CD such as poly-β-CD-C6 or (ii) coating of non-ionic 6-O-capro-β-CD with the cationic polymer chitosan (CS). Uncoated 6-O-capro-β-CD negatively charged NPs were used as control formulation. Results and Discussion Fabrication and in vitro characterization of
- the relaxation of the polymer chain begins and accelerates the release in SIF. When a further evaluation was made for the CS-(6-O-capro-β-CD), which showed a high correlation between the two models, the diffusional exponent values of the Korsmeyer–Peppas and Peppas–Sahlin models were calculated as
- 1.039 and 0.450, respectively. Similarly, the n value of Korsmeyer–Peppas above 0.85 indicates that the release mechanism is realized by super case II [44]. This value was interpreted as indicative of the release seen with the erosion of the nanoparticle material and the initiation of polymer relaxation
Nostochopcerol, a new antibacterial monoacylglycerol from the edible cyanobacterium Nostochopsis lobatus
Beilstein J. Org. Chem. 2023, 19, 133–138, doi:10.3762/bjoc.19.13
- , antifoamers, preservatives, antistatic agents, polymer lubricants, and mold-releasing agents for the production of foods, cosmetics, ointments, paints, and plastics [33]. Compound 1 exhibited antibacterial activity, evaluated by a microculture method, with MIC 50 μg/mL against B. subtilis ATCC6633 and 100 μg
- ) to see the separation of activity at the top two and slow-eluting fractions. The top fraction was purified by repeated HPLC first on an ODS column (Cosmosil AR-II 1 × 25 cm) and second on a styrene-divinylbenzene polymer column (Hamilton PRP-1 1 × 25 cm) both eluted with MeCN/50 mM NaClO4 75:25 to
Inline purification in continuous flow synthesis – opportunities and challenges
Beilstein J. Org. Chem. 2022, 18, 1720–1740, doi:10.3762/bjoc.18.182
- chromatography system which utilizes multiple columns in parallel with a series of valves to stagger the injection of crude material to each of the column lines. The columns are filled with a diethylaminopropyl-functionalized polymer, followed by an UV–vis detector to identify and separate the different peaks
- heterogeneous fashion. This oftentimes leads to improved green credentials, safety, and sometimes efficiency, especially when it is applied to the downstream process. Commercially available resins, activated charcoal, polymer-supported species that trap spent reagents or side-products as well as related
Molecular and macromolecular electrochemistry: synthesis, mechanism, and redox properties
Beilstein J. Org. Chem. 2022, 18, 1505–1506, doi:10.3762/bjoc.18.158
- , polymer electrolyte membrane electrolysis technology, and new methods coupled with photoredox catalysts or transition metal catalysis, resulting in remarkable progress in organic electrosynthetic processes. Theoretical calculations have also led to a better understanding of the electron transfer behavior
Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface
Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156
- how available Cu-based electrosynthetic reactions can be used to calibrate electrochemical signals on a polymer-coated electrode array and delineate the factors to be considered when choosing a polymer surface for such a study. Keywords: calibration of binding curves; electrochemical signaling
- development of polymer-coated arrays that capitalize on the versatility of diblock copolymers as surface coatings (Figure 2) [17][18][19]. In the polymer, one of the blocks is used to place attachment sites for molecules above the electrodes (the arylbromide or arylborate block in the polymer shown), and the
- other block is used to provide a site for cross-linking the polymer in order to render the surface more stable once it is coated onto an array (the cinnamate block is used to make a polymer network through photochemical cross-linking). The use of the borate ester surface provides a tunable surface that
1,4,6,10-Tetraazaadamantanes (TAADs) with N-amino groups: synthesis and formation of boron chelates and host–guest complexes
Beilstein J. Org. Chem. 2022, 18, 1424–1434, doi:10.3762/bjoc.18.148
- dynamic covalent libraries [25]. TAAD can be covalently bound to a polymer matrix through the nucleophilic nitrogen N(1) that was used to prepare scavengers of boronic acids [25]. Also, TAAD was demonstrated to serve as a scorpionate-type ligand for manganese and iron leading to complexes with the metal
Computational model predicts protein binding sites of a luminescent ligand equipped with guanidiniocarbonyl-pyrrole groups
Beilstein J. Org. Chem. 2022, 18, 1322–1331, doi:10.3762/bjoc.18.137
- electrostatic potential grid into energy grids suitable for the Hamiltonian, chemically relevant polymer fragments were used as molecular probes in Epitopsy [26]. Epitopsy is a tool designed to calculate the electrostatic energy of a protein–ligand system from the protein potential grid and ligand charge
- in the context of polymer studies [33][34][35]. Our model is a chain of five beads, GCP-Lys-AIE-Lys-GCP, with each pair of neighbors in the chain connected by a harmonic spring potential (Figure 1b). Given the symmetry of 1, there are two types of springs, GCP-Lys and Lys-AIE. The spring parameters
Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells
Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136
- where the emissive layer also contained an inorganic salt and a conducting polymer. Recently, a step-change in device performance were achieved by He et al. who employed a cationic TADF compound that possesses low-lying through-space and through-bond charge transfer excited states [23]. The LEEC showed
Make or break: the thermodynamic equilibrium of polyphosphate kinase-catalysed reactions
Beilstein J. Org. Chem. 2022, 18, 1278–1288, doi:10.3762/bjoc.18.134
- ; Introduction Polyphosphate (polyP, Figure 1) is a linear polymer of up to thousands of phosphate residues connected by phosphate anhydride bonds. It serves as a phosphate storage molecule and plays a crucial role in biofilm formation and stress responses of cells [1]. So far polyP has been detected in every
Polymer and small molecule mechanochemistry: closer than ever
Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128
- (mechanochemistry) can be accomplished through various experimental strategies. Among them, ultrasonication of polymeric matrices and ball milling of reaction partners have become the two leading approaches to carry out polymer and small molecule mechanochemistry, respectively. Often, the methodological differences
- between these practical strategies seem to have created two seemingly distinct lines of thought within the field of mechanochemistry. However, in this Perspective article, the reader will encounter a series of studies in which some aspects believed to be inherently related to either polymer or small
- molecule mechanochemistry sometimes overlap, evidencing the connection between both approaches. Keywords: ball milling; mechanochemistry; mechanophore; polymer; pulsed ultrasonication; Introduction In the past two decades, the growth in popularity of mechanochemistry has been unmistakable. During this
From amines to (form)amides: a simple and successful mechanochemical approach
Beilstein J. Org. Chem. 2022, 18, 1210–1216, doi:10.3762/bjoc.18.126
- assistance with the generation of the 1H, 13C NMR, and GC–MS spectroscopic data. Funding This research was funded by MIUR Italy, PRIN 2017 project (grant number: 2017B7MMJ5_001) “MultIFunctional poLymer cOmposites based on groWn matERials (MIFLOWER) and Fondazione di Sardegna (FdS, F72F20000230007).
Heterogeneous metallaphotoredox catalysis in a continuous-flow packed-bed reactor
Beilstein J. Org. Chem. 2022, 18, 1123–1130, doi:10.3762/bjoc.18.115
- colour of the polymer in the packed bed turned rapidly black (see Supporting Information File 1, Figure S4), and lower yields were observed (Table 1, entries 6 and 7). The catalyst deactivation could be due to the formation of nickel-black [28], or via (photo-)thermal degradation of the polymer. Packed
Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials
Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94
- example, ITIC (10), is shown in Figure 4. ITIC [17], in combination with polymer 11, achieved a power conversion efficiency (PCE) of 6.8%, which was the best value for NFA organic solar cells at the time of publication. Fluorination of ITIC, obtaining IT-4F (12), shown in Figure 5, reduced ELUMO. Combined
- with the donor polymer 13, PCEs up to 17% were achieved [8]. More recently, another fused-thiophene containing NFA was published, Y6 (14), shown in Figure 6 [30]. Y6 held the record for the highest value of an OPV with PCEs up to 18% upon blending with polymer 15 [31]. This has now been surpassed; in
- 2021, Hou et al. reported a ternary OPV, using a mixture of the novel PBQx-TF (16) donor polymer and the non-fullerene acceptor eC9-2Cl (17), shown in Figure 7. In addition, a third material, F-BTA3 (18) was blended in [32]; all three materials are fused thiophene systems. The resulting OPV achieved a
Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons
Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83
- . In 2002, Monkman reported the addition of camphor sulfonic acid (CSA) to the fluorescent polymer poly{2,5-pyridylene-co-1,4-[2,5-bis(2-ethylhexyloxy)]phenylene} (compound 1 in Figure 2) containing pyridine groups led to the protonation effect [26]. CSA has strong acidity and low volatility, which is
- (C6F5)3 (BCF) to bind to nitrogen atoms at the basic site a of π-conjugated polymer, providing a simple strategy to regulate the optical properties of the A–D–A chromophore with charge transfer excited state properties [28]. In 2019, Wang et al. constructed a novel exciplex system by using the Lewis
- substituents on the benzene rings of B(C6F5)3 is responsible for its stronger Lewis acidity compared to B(C6H5)3, and reacted efficiently with the basic fluorescent materials. In 2011, Hayashi investigated the modification of pyridyl-conjugated polymer films with the Lewis acid BF3 [31]. Through repeated acid
A trustworthy mechanochemical route to isocyanides
Beilstein J. Org. Chem. 2022, 18, 732–737, doi:10.3762/bjoc.18.73
- Ricerca d'Ateneo) core facility of the University of Cagliari and Dr. Sandrina Lampis for assistance with the generation of the 1H and 13C NMR spectroscopic data. Funding This research was funded by MIUR Italy, PRIN 2017 project (grant number: 2017B7MMJ5_001) “MultIFunctional poLymer cOmposites based on
BINOL as a chiral element in mechanically interlocked molecules
Beilstein J. Org. Chem. 2022, 18, 508–523, doi:10.3762/bjoc.18.53
- the axle, placing it away from the polymer backbone. By N-acylation of the ammonium group, a shuttling of the macrocycle towards the ester moiety is achieved, placing the chiral information of the macrocycle in closer proximity to the polymer backbone (polymers 33). The influence of the chiral BINOL
- unit on the helicity of the polyacetylene was investigated by CD spectroscopy. Here, no chiral induction was observed for the ammonium species 32, while the N-acylated polymers 33 showed clear Cotton effects in the absorption range of the polymer main chain (490 nm), demonstrating an effective
Substituent effect on TADF properties of 2-modified 4,6-bis(3,6-di-tert-butyl-9-carbazolyl)-5-methylpyrimidines
Beilstein J. Org. Chem. 2022, 18, 497–507, doi:10.3762/bjoc.18.52
- toluene solutions as well as 1 wt % PMMA (poly(methyl methacrylate)) films. The solid-state samples were prepared by dissolving the compounds and polymer or host material at appropriate ratios in toluene solution and then wet-casting the solutions on quartz substrates. The absorption spectra were recorded
Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions
Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31
- polymer) (Co@imine-POP) has been synthesized by immobilizing cobalt onto a nitrogen-rich porous organic polymer (Scheme 20) [35]. Using scanning electron microscopy, the surface morphology of the catalyst was evaluated. Nowadays, covalent organic frameworks (COF) were found to be a suitable support in
- reaction (Scheme 31). Non-nanoparticle-based protocols Nanoparticles are materials with sizes around nanometer scales. The used nanoparticles are environmentally friendly magnetic cross-linked chitosan fibers which is a natural polysaccharide polymer. In this regard the use of such polymers is promising
Green synthesis of C5–C6-unsubstituted 1,4-DHP scaffolds using an efficient Ni–chitosan nanocatalyst under ultrasonic conditions
Beilstein J. Org. Chem. 2022, 18, 133–142, doi:10.3762/bjoc.18.14
- . Chitosan is one of the most abundant bio-based polymers in nature [9]. It is the N-deacetylated form of chitin found in industrial waste [10]. Chitosan is a broadly used natural polymer because of properties such as biocompatibility, low cost, and nontoxicity. It has diverse applications, such as drug
Study on the interactions between melamine-cored Schiff bases with cucurbit[n]urils of different sizes and its application in detecting silver ions
Beilstein J. Org. Chem. 2021, 17, 2950–2958, doi:10.3762/bjoc.17.204
- supermolecule polymer with TBT due to its larger cavity. Since Q[7] and TBT form a host–guest complex, the carboxyl group at the end of TBT and the carbonyl group of the Q[7] still have a strong ability to coordinate with metals. Therefore, Q[7]-TBT is selected for the detection of silver ions (Ag+) [32][33
Polymer chemistry: fundamentals and applications
Beilstein J. Org. Chem. 2021, 17, 2922–2923, doi:10.3762/bjoc.17.200
- Bernhard V. K. J. Schmidt School of Chemistry, University of Glasgow, G12 8QQ Glasgow, UK 10.3762/bjoc.17.200 Keywords: polymer chemistry; Ever since the introduction of the term macromolecule and the early days of polymer science [1], organic chemistry and polymer chemistry have been closely
- related [2]. It only seems to be a logical step to give room for a thematic issue on polymer chemistry in the Beilstein Journal of Organic Chemistry. The connection between organic and polymer chemistry has been highlighted frequently [3][4], up to the point where one can talk about macroorganic chemistry
- , where oligomers bring molecular precision from organic chemistry together with materials properties from polymer chemistry [5]. Especially in the challenge of transformation to a more sustainable polymer science, organic chemistry can give significant support in the development of greener polymer
A two-phase bromination process using tetraalkylammonium hydroxide for the practical synthesis of α-bromolactones from lactones
Beilstein J. Org. Chem. 2021, 17, 2906–2914, doi:10.3762/bjoc.17.198
- polymerization (ATRP) reactions and functional polymer synthesis [29][30][31][32][33][34]. Although α-bromo-γ-butyrolactone, which is a five-membered lactone, is easily accessible from the five-membered lactone by some bromination methods [35][36], the bromination method for the six-membered lactone, δ
Effect of a twin-emitter design strategy on a previously reported thermally activated delayed fluorescence organic light-emitting diode
Beilstein J. Org. Chem. 2021, 17, 2894–2905, doi:10.3762/bjoc.17.197
- other high molecular weight emitters can show at least some degree of orientation in solution-processed films. For instance, Senes et al. [23][24]. showed that the OPVn series of polymers exhibited higher horizontal orientation by increasing the length of the polymer chain, and by extension the molecule
Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches
Beilstein J. Org. Chem. 2021, 17, 2621–2628, doi:10.3762/bjoc.17.175
- University Jena, Philosophenweg 7, 07743 Jena, Germany 10.3762/bjoc.17.175 Abstract Controlling the length of one-dimensional (1D) polymer nanostructures remains a key challenge on the way toward the applications of these structures. Here, we demonstrate that top-down processing facilitates a
- straightforward adjustment of the length of polyethylene oxide (PEO)-based supramolecular polymer bottlebrushes (SPBs) in aqueous solutions. These cylindrical structures self-assemble via directional hydrogen bonds formed by benzenetrisurea (BTU) or benzenetrispeptide (BTP) motifs located within the hydrophobic
- methods represent an easily implementable technique toward 1D polymer nanostructures with an adjustable length in the range of interest for perspective biomedical applications. Keywords: distribution; dual centrifugation; filomicelles; self-assembly; ultrasonication; Introduction Cylindrical polymer
Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing
Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171
- ; Introduction Gels can be defined as polymer networks that are expanded throughout their whole volume by a fluid. In the case of hydrogels, the network component is a hydrophilic polymer, and the swelling agent is water [1]. However, their lack of interconnected macropores and elasticity, required properties
- solution is then cooled to below the freezing point of water, whereby ice crystals form. Importantly, here the solvent (water) solidifies (freezes) and forms solid solvent porogens within the structure allowing the polymer network to form around these crystals, templating the porous structure of the final
- properties Cryogels are macroporous hydrogels with interconnected porosity, with high swelling capacities and large surface areas. Ultimately, many of the final cryogel properties are dependent on the choice of polymer/monomer composition used. However, other factors such as crosslinking, pore size, wall
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