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Search for "supramolecular" in Full Text gives 526 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
A tribute to Carsten Schmuck
Beilstein J. Org. Chem. 2021, 17, 2795–2798, doi:10.3762/bjoc.17.190
- chemistry to advanced supramolecular chemistry, and he always had an open ear for the questions and concerns of students, both in his role as a professor and as the Dean of Chemistry. But he did not stop there: When he had the feeling that the current chemistry textbooks did not fully meet the needs of his
- development of the noncovalent and supramolecular recognition research in the European Research Area (ERA). His personal and scientific engagement was equally intensive with excellent, well-established scientists, and new groups from small scientific communities; for instance, starting collaboration in the
- , at which Carsten was the head of the work group WG0018/05, entitled “Guanidinium as an important anchor group in supramolecular recognition”. At that time, the focus of WG0018/05 was mostly on nonaqueous anion recognition systems and constructs, but during our several discussions and mutual visits
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
- 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
- the conditions for the assembly process, and are therefore often limited to specific materials. An alternative is the use of molecular motifs capable of forming directional supramolecular interaction forces, such as hydrogen bonds or π-interactions, to guide the one-dimensional (1D) assembly of
- established, commercial polymers in solution [17]. We recently reported the self-assembly of polyethylene oxide (PEO) polymers into cylindrical nanostructures, also called supramolecular polymer bottlebrushes (SPBs), based on the end group modification with hydrogen bond forming benzenetrisurea (BTU) and
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
- allowing syringe injectability [9]. It has been suggested that cryogels are more suitable for this application, as opposed to hydrogels, as a greater number of cells can be contained within the structure. With an exemption for injectable supramolecular hydrogel systems, which have been demonstrated to
In-depth characterization of self-healing polymers based on π–π interactions
Beilstein J. Org. Chem. 2021, 17, 2496–2504, doi:10.3762/bjoc.17.166
- of Photonic Technology (IPHT), e. V. Jena, Albert-Einstein-Straße 9, 07745 Jena, Germany 10.3762/bjoc.17.166 Abstract The self-healing behavior of two supramolecular polymers based on π–π-interactions featuring different polymer backbones is presented. For this purpose, these polymers were
- mechanical behavior was studied using rheology. The activation of the supramolecular interactions results in a breaking of these noncovalent bonds, which was investigated using IR spectroscopy, leading to a sufficient increase in mobility and, finally, a healing of the mechanical damage. This scratch-healing
- behavior was also quantified in detail using an indenter. Keywords: characterization of polymers; π–π-interactions; self-healing polymers; supramolecular polymers; Introduction Damage inflicted on different materials is omnipresent. Consequently, nature established a mechanism dealing with this problem
Halides as versatile anions in asymmetric anion-binding organocatalysis
Beilstein J. Org. Chem. 2021, 17, 2270–2286, doi:10.3762/bjoc.17.145
- a field. Thus, the use of the halide in the catalyst–anion complex as both a mere counter-anion spectator or an active nucleophile has been depicted, along with the new trends toward additional noncovalent contacts within the HB-donor catalyst and supramolecular interactions to both the anion and
- challenging to design small molecule catalysts that resemble anion-binding properties of enzymes. Hence, a major challenge of small organic receptors to mimic nature’s capability of binding to the targeted anions resides in the supramolecular properties of enzymes and co-factors to form exact matching binding
- anion coordination and supramolecular chemistry [7][8][9][10][11], this field of research has attracted more attention within the past two decades. Immense efforts were made to identify small molecules that are able to productively bind anions via noncovalent hydrogen bonding, from which cationic
Constrained thermoresponsive polymers – new insights into fundamentals and applications
Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138
- detail. According to the type of supramolecular interactions governing the thermoresponsive behavior UCST type polymers can be classified into two categories. Although various molecular forces such as van der Waals interactions and hydrophobic effects contribute to the thermoresponsiveness of polymers
Design, synthesis and photophysical properties of novel star-shaped truxene-based heterocycles utilizing ring-closing metathesis, Clauson–Kaas, Van Leusen and Ullmann-type reactions as key tools
Beilstein J. Org. Chem. 2021, 17, 1374–1384, doi:10.3762/bjoc.17.96
- macrocycles [31][32]. Moreover, polypyrrolic systems are of extensive interest in numerous areas namely optics, medicine, and supramolecular chemistry in addition to the materials sciences and technology. Fascinatingly, in luminescence as well as fluorescence-based sensors, pyrrole derivatives play a vital
Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring
Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92
- represents a family of materials where variety of synthetic routes can be applied to form photoactive matter with altered properties, i.e., monomer supramolecular assembly to attain a monomer complex prior to carbonization results in enhanced porosity and photoactivity since ordered structures are formed
- of this study, which is divided into two parts, the hydrogel denoted as HGCM was utilized as the main substrate for both sections. To prepare HGCM, firstly graphitic carbon nitride was synthesized from the thermal treatment of a cyanuric acid–melamine supramolecular complex (CM) [42]. The resulting
- , 95%, Sigma-Aldrich), sodium chloride (NaCl, 99%, Sigma-Aldrich), sodium hydroxide (1 M solution, Sigma-Aldrich). DMA, PEGDMA, PEGMEMA and were passed through basic alumina column prior to use. Synthesis of g-CN: g-CN was synthesized from cyanuric acid–melamine supramolecular complex as reported in
Structural effects of meso-halogenation on porphyrins
Beilstein J. Org. Chem. 2021, 17, 1149–1170, doi:10.3762/bjoc.17.88
- , Trinity College Dublin, The University of Dublin, Dublin 2, Ireland Van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands 10.3762/bjoc.17.88 Abstract The use of halogens in the crystal engineering of supramolecular porphyrin assemblies
- we were able to deduce the impact a meso halogen has on a porphyrin, for example, meso-halogenation is dependent on the type of alternate substituents present when forming supramolecular assemblies. Furthermore, we have designed a method to predict the conformation of halogenated porphyrins, without
- their relative versatility in areas such as directionality, the tunability of the σ-hole, hydrophobicity, and donor atom size [14]. These traits allow for the design of novel supramolecular architectures which are directive and reproducible, without relying on the hydrogen-bonding functionality which in
Synthesis of dibenzosuberenone-based novel polycyclic π-conjugated dihydropyridazines, pyridazines and pyrroles
Beilstein J. Org. Chem. 2021, 17, 719–729, doi:10.3762/bjoc.17.61
- ], and self-assembled supramolecular architectures [48]. On the other hand, many natural compounds that contain a pyrrole core, such as bilirubin, hemoglobin, chlorophyll a, and vitamin B12, are very important for life. In addition to being common in natural products and biological systems, the active
Identification of volatiles from six marine Celeribacter strains
Beilstein J. Org. Chem. 2021, 17, 420–430, doi:10.3762/bjoc.17.38
- between the sulfur and an ester oxygen. This phenomenon was first described in supramolecular structures by Gleiter [59] and later also used to explain the outcome of organocatalytic reactions [60]. The pure stereoisomers of 42 were isolated by preparative HPLC, for which the best separation was achieved
19F NMR as a tool in chemical biology
Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28
- understand their functions. However, because the formation of a stabilized G-quadruplex causes an overall reduction in the tumbling rates of the molecule, and thus a great decay of NMR signal sensitivity, analysis of these supramolecular structures by common NMR techniques has proved challenging. To overcome
- examples demonstrate that 19F NMR offers a suitable and non-perturbing approach by which to access detailed structural information of complex DNA and RNA folding topologies and sophisticated supramolecular assemblies. Metabolism studies Biotransformation of fluorinated xenobiotics Fluorine is present in a
Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies
Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17
- building blocks for the ternary electrostatic self-assembly, forming well-defined supramolecular assemblies with tunable sizes of 50 to 500 nm. Due to the network of possible chemical reactions for the anthocyanidin and the excited-state dissociation of the photoacid upon irradiation, different ways to
- particles, and information on the molecular structure was gained by UV–vis spectroscopy. Isothermal titration calorimetry (ITC) provided information on the thermodynamics and interaction forces in the supramolecular assembly formation. Keywords: electrostatic self-assembly; hydroxyflavylium
- ; multiswitchable; photoacid; polyelectrolyte; Introduction Supramolecular nanoscale assemblies responding to multiple stimuli are highly desirable in various fields including transport systems, sensors, and optoelectronic applications [1][2][3][4][5][6][7][8]. Self-assembly into supramolecular structures and
Insight into functionalized-macrocycles-guided supramolecular photocatalysis
Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15
- with various macrocyclic hosts as well as on the role of macrocyclic-hosts-assisted hybrid materials in energy transfer. To keep the clarity of this review, the macrocycles are categorized into the most commonly used supramolecular hosts, including crown ethers, cyclodextrins, cucurbiturils
- , calixarenes, and pillararenes. This minireview not only summarizes the role that macrocycles play in photocatalytic reactions but also clarifies the photocatalytic mechanisms. Finally, the future research efforts and new pathways to apply macrocycles and supramolecular hybrid materials in photocatalysis are
- also discussed. Keywords: host–guest chemistry; macrocycles; noncovalent interactions; supramolecular photocatalysis; Introduction Enzyme-catalyzed reactions are often carried out fantastically in nature via noncovalent interactions of a substrate [1][2]. Inspired by these natural processes, chemists
Tuning the solid-state emission of liquid crystalline nitro-cyanostilbene by halogen bonding
Beilstein J. Org. Chem. 2021, 17, 124–131, doi:10.3762/bjoc.17.13
- tuning of the fluorescence behaviour and mesomorphic properties of the assemblies. Keywords: fluorescence; halogen bonding; liquid crystal; Introduction Supramolecular chemistry has proven to be an efficient approach for the development of novel smart materials, since it relies on non-covalent
- supramolecular liquid crystals, especially hydrogen bonding and halogen bonding have gained considerable attention [3][4][5][6][7]. In 2004, Bruce and co-workers reported the first example of a halogen-bonded liquid crystal based on pentafluoroiodobenzene and 4-alkoxystilbazole [5]. Ever since, several other
- behaviour of halogen-bonded liquid crystals has been reported. In 2014, Tothadi and Desiraju reported on a new supramolecular synthon based on the non-covalent interaction between 1,4-dinitrobenzene and iodobenzene [13]. Their structural analysis of a series of ternary cocrystals revealed that the nitro
Supramolecular polymers with reversed viscosity/temperature profile for application in motor oils
Beilstein J. Org. Chem. 2021, 17, 105–114, doi:10.3762/bjoc.17.11
- , 64293 Darmstadt, Germany 10.3762/bjoc.17.11 Abstract We report novel supramolecular polymers, which possess a reversed viscosity/temperature profile. To this end, we developed a series of ditopic monomers featuring two self-complementary binding sites, either the guanidiniocarbonyl pyrrole carboxylic
- acid (GCP) or the aminopyridine carbonyl pyrrole carboxylic acid (ACP). At low temperatures, small cyclic structures are formed. However, at elevated temperatures, a ring–chain transformation leads to the formation of a supramolecular polymer. We demonstrate that this effect is dependent on the
- identification of one compound as a promising VII. Keywords: noncovalent interactions; polymers; ring-chain transformation; supramolecular chemistry; viscosity; Introduction Viscosity index improvers (VIIs) are used to counteract the loss of viscosity of working fluids (such as motor oils) at elevated
Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders
Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10
- ionic strength on the supramolecular polymerization was probed via circular dichroism spectroscopy and cryogenic transmission electron microscopy. Physiological salt concentrations efficiently screen the charges of the dendritic building block equipped with eight sulfate groups and trigger the formation
- of rigid supramolecular polymers. Since multivalent sulfated supramolecular structures mimic naturally occurring L-selectin ligands, the corresponding affinity was evaluated using a competitive SPR binding assay and benchmarked to an ethylene glycol-decorated supramolecular polymer. Keywords: L
- -selectin binders; multivalency; self-assembly in water; supramolecular polymers; Introduction Deciphering the interaction of artificial molecular building blocks with biological components is a key element on the way to understanding and selectively manipulating biological systems. Throughout nature
Circularly polarized luminescent systems fabricated by Tröger's base derivatives through two different strategies
Beilstein J. Org. Chem. 2021, 17, 52–57, doi:10.3762/bjoc.17.6
- the rac-TBPP/DGG co-gel, implying the formation of the ordered packing of rac-TBPP in supramolecular assemblies. At the molar ratio of rac-TBPP/DGG = 1:80, The FTIR spectrum was similar to that of the DGG gel, in which νC=O bonds at 1729, 1691, and 1645 cm−1 reveal that the carboxyl acid groups of DGG
- scanning electron microscope (SEM). At the molar ratio of rac-TBPP/DGG = 1:80, the co-gel shows belt-like nanofibers (Figure 3c), while the fibrous morphology could not be observed at the molar ratio of 1:16 (Figure 3d). It indicates that two different kinds of supramolecular assemblies were formed at the
- the co-assembly strategy. The cogels show significant CPL emission and stoichiometry-controlled inversion of chirality due to the hydrogen bonding interactions and packing modes in the supramolecular co-assemblies. Owing to TB special V-shaped structure, rigid conformation, and nitrogen stereogenic
Control over size, shape, and photonics of self-assembled organic nanocrystals
Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5
- . Funding This work was supported by grants from the Israel Science Foundation, Minerva Foundation, Schmidt Minerva Center for Supramolecular Architectures, and the Helen and Martin Kimmel Center for Molecular Design.
The fluorescence of a mercury probe based on osthol
Beilstein J. Org. Chem. 2021, 17, 22–27, doi:10.3762/bjoc.17.3
- Guangyan Luo Zhishu Zeng Lin Zhang Zhu Tao Qianjun Zhang Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, China 10.3762/bjoc.17.3 Abstract The ability of osthol (OST) to recognize mercury ions in aqueous solution was studied using
Chiral anion recognition using calix[4]arene-based ureido receptors in a 1,3-alternate conformation
Beilstein J. Org. Chem. 2020, 16, 2999–3007, doi:10.3762/bjoc.16.249
- most important branches of modern supramolecular chemistry, as can easily be demonstrated by an immense number of recent reviews [1][2][3][4][5][6] and books [7][8][9][10][11] devoted to this topic. Due to the omnipresence of anions in biological systems, their irreplaceable roles in cell functioning
- same time, the carbonyl groups from the neighbouring receptor urea moieties interacted with the C–H bonds of the DMSO methyl group (the C=O···H–C distances were 2.486 and 2.452 Å), thus forming the calixarene dimer with a head-to-tail mutual orientation. The overall supramolecular binding motif was
Selected peptide-based fluorescent probes for biological applications
Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247
- insulin Schmuck and co-workers reported a supramolecular ensemble in combination of a pyrene-tagged amphiphilic peptide beacon (6) and a macrocyclic host (cucurbit[8]uril, CB[8]) for ratiometric fluorescent detection of amino acid derivatives, specific peptides, and proteins in aqueous media (Figure 6
- Attribution 3.0 Unported Licence, https://creativecommons.org/licenses/by/3.0/. Published by The Royal Society of Chemistry. Acknowledgements The author would like to thank late Prof. Dr. Carsten Schmuck for his exceptional contribution to Supramolecular Chemistry and Peptide Chemistry research.
Naphthalonitriles featuring efficient emission in solution and in the solid state
Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246
- parallel (see Figure 2B), the centroid distance between the rings reaches up to 4.985 Å, suggesting that the intermolecular π–π interactions are absent. In addition to these interactions, there also exist weak supramolecular N–H interactions. Firstly, two Me units form dimeric structures that are connected
- generate one-dimensional supramolecular chain-like arrays with tolyl units distributed at the two sides of the chain (Figure 2C). These weak forces help the molecules to minimize the energy loss via non-radiative relaxation channels by rigidifying their conformation [25]. Photophysical characterization of
Construction of pillar[4]arene[1]quinone–1,10-dibromodecane pseudorotaxanes in solution and in the solid state
Beilstein J. Org. Chem. 2020, 16, 2954–2959, doi:10.3762/bjoc.16.245
- the further capping of the pseudorotaxanes to construct rotaxanes. Keywords: host–guest chemistry; pillar[4]arene[1]quinones; pillararenes; pseudorotaxanes; supramolecular chemistry; Introduction Relying on the research of basic science, supramolecular chemistry has become an important mean for
- constructing functional materials from the bottom up as well as an important way to create new substances with functions [1][2][3][4][5]. Through ingenious designs and the applications of molecular recognition and self-assembly strategies, many exquisite supramolecular architectures have been fabricated
- , including molecular switches, molecular logic gates, molecular machines, supramolecular polymers, etc. [6][7][8][9][10][11]. Pseudorotaxanes not only are used as the supramolecular precursors for the synthesis of rotaxanes and catenanes but also play an important role in the construction of supramolecular
UV resonance Raman spectroscopy of the supramolecular ligand guanidiniocarbonyl indole (GCI) with 244 nm laser excitation
Beilstein J. Org. Chem. 2020, 16, 2911–2919, doi:10.3762/bjoc.16.240
- , Universitätsstrasse 7, 45141 Essen, Germany 10.3762/bjoc.16.240 Abstract Ultraviolet resonance Raman (UVRR) spectroscopy is a powerful vibrational spectroscopic technique for the label-free monitoring of molecular recognition of peptides or proteins with supramolecular ligands such as guanidiniocarbonyl pyrroles
- (GCPs). The use of UV laser excitation enables Raman binding studies of this class of supramolecular ligands at submillimolar concentrations in aqueous solution and provides a selective signal enhancement of the carboxylate binding site (CBS). A current limitation for the extension of this promising
- selectivity for monitoring the CBS, but the resulting UVRR spectrum overlaps with the UV-excited autofluorescence from the aromatic binding partners. This necessitates the use of a laser excitation <260 nm for spectrally separating the UVRR spectrum of the supramolecular ligand from the UV-excited
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