Herein, we demonstrate how Cl, Br, and I substitutions influence supramolecular hydrogelation in glycosylated N-methylhalogenomaleimide amphiphiles. Bromine provides favourable intermolecular cohesion, yielding efficient and thermally robust hydrogels. Single-crystal X-ray analysis suggests cooperative hydrogen-bonding networks along with short Br⋯Br contacts, indicating that halogen bonds may serve as a tunable design element for functional soft materials.

ABSTRACT Three Gastrodin derivatives, each containing a fluorescent s ‐tetrazine moiety and alkyl chains with different lengths and branching structures, were newly synthesized to clarify how alkyl chain structure governs the formation of organized molecular films. s ‐Tetrazine derivatives possess the intriguing characteristic that their luminescence behavior changes sensitively in response to molecular packing; structural transitions may potentially reveal novel luminescent properties. Each derivative formed a stable monolayer on the water surface and exhibited systematic behavioral changes depending on the hydrophobic chain length and the presence or absence of branching. Although no significant differences were observed in the mesoscopic morphologies formed within monolayers, the variations in behavior on the water surface led to differences in the orderliness of the layer structures within the multilayers. Furthermore, the absorption and fluorescence behaviors of the two‐dimensional molecular films differed from those of the corresponding three‐dimensional solids. This result indicates that chemical structure and packing of alkyl chains play a key role in controlling molecular packing and photophysical behavior in organized films.

Applying vibrational circular dichroism (VCD) spectroscopy, we directly reveal hydrated-state supramolecular chirality in K+-responsive chiral supramolecular hydrogels. Combined VCD and induced circular dichroism measurements confirmed that K+-triggered self-assembly enables long-range chirality transfer from a chiral D- or L-alanine residue to an otherwise achiral supramolecular framework.

In this study, we developed glycosylated N-methylbromomaleimide-based supramolecular hydrogels exhibiting colour change along with gel-sol transition and found that the stereoisomerism of the saccharide residue affects their gelation ability. Single-crystal X-ray diffraction analysis revealed the molecular packing and hydrogen-bonding networks contributed by the saccharide residues. Interestingly, it was found that water molecules were incorporated into the hydrogen-bonding network in the crystals of the compounds that showed gelation ability.

We developed a novel benzo-15-crown-5 (B15C5)-based organic ligand containing an N-phenylchloromaleimide moiety. Two geometrically different potassium cation (K+) complexes with a B15C5/K+/B15C5 sandwich structure were prepared and characterised via single-crystal X-ray diffraction.

We developed a novel supramolecular hydrogelator possessing a benzo-15-crown-5 (B15C5) moiety. The hydrogelator can detect colourless potassium cations (K+) via easily readable gelation and colour change arising from a change in the molecular assembling ability through host-guest interactions between B15C5 and K+, which afford a B15C5/K+/B15C5 sandwich complex.

The multifunctionality of galectins helps regulate a broad range of fundamental cellular processes via cis ‐binding and trans ‐bridging activities and has gained widespread attention with respect to the importance of the natural specificity/selectivity of this lectin family to its glycoconjugate receptors. Combining galectin (Gal)‐1, −3, −4, and −9 variant test panels, achieved via rational protein engineering, and a synthetic α‐dystroglycan (DG) O ‐Mannosylated core M1 glycopeptide library, a detailed comparative analysis was performed, utilizing microarray experiments to delineate the design‐functionality relationships within this lectin family. Enhancement of prototype Gal‐1 and chimera‐type Gal‐3 cis ‐binding toward the prepared ligands is possible by transforming these lectins into tandem‐repeat type and prototypes, respectively. Furthermore, Gal‐1 variants demonstrated improved trans ‐bridging capabilities between core M1 α‐DG glycopeptides and laminins in microarray, suggesting the possible translational applications of these galectin variants in the treatment of some forms of α‐dystroglycanopathy.

64IV. Determination of the diastereoselectivity in the enantioselective addition of diethylzinc •VI. Detailed retrosynthetic analysis and final elaboration to the synthesis of sphingofungin E • ••••••••••

Seek a cell anchorage galectin bridge: Transforming the wildtype Galectin (Gal)-1 and -3 to a tandem-repeat type variant via rational protein engineering enhanced cis-binding activity with O-Mannosylated core M1 glycopeptides of α-dystroglycan (DG). Furthermore, the Gal-1 variants (but not Gal-3 variants) demonstrated trans-bridging activity with the prepared α-DG core-M1 glycoconjugates and laminins in situ via the carbohydrate-protein interactions. Thus, Gal-1 and its variants are exciting candidates for treating several forms of muscular dystrophy. More information can be found in the Research Article by H. Kaltner, H. Hinou, et al.

Enantioselective synthesis of the marine natural product (+)-agelasidine A has been achieved by taking advantage of [1,3]-chirality transfer from enantiomerically enriched α-silyl farnesol through a key thio-Claisen rearrangement. The optical rotation of the hydrochloride salt of the synthetic substance confirmed that natural (+)-agelasidine A has the S-configuration at its C-10 stereogenic center.

Supramolecular hydrogels formed by self-assembly of low-molecular-weight amphiphiles (hydrogelators) in water via multiple weak non-covalent interactions have attracted considerable attention as functional soft materials. Because the supramolecular hydrogels can immobilise artificial- or bio-molecules under semi-wet conditions without drying or troublesome chemical processes, their application as biomaterials has been actively attempted. In this field, saccharides have been considered as important components of hydrogelators, as they are biocompatible and not only function as hydrophilic groups but also serve as hydrogen bonding sites due to the several hydroxyl groups present in their structure. In this mini-review, recent advances in the use of saccharides in supramolecular hydrogels research are introduced.

We developed glycolipid-type amphiphiles with a small anilinochloromaleimide-based luminogen, H-AAC-C6-Ph-MS (monosaccharide, MS=alpha or beta-D-glucose (Glc), alpha or beta-D-galactose (Gal), or alpha-D-mannose (Man)) exhibiting aggregation-induced emission (AIE) features. Interestingly, the AIE properties of the amphiphiles depend on the epimerism of MS moiety. For instance, H-AAC-C6-Ph-alpha Man did not show fluorescence in the aggregate state, whereas the other amphiphiles exhibited fluorescence in the aggregate state. The findings strongly suggest that the design of molecular packing is important to control the AIE features.

Dystroglycan (DG), which constitutes a part of the dystrophin–glycoprotein complex, connects the extracellular matrix to the cytoskeleton. The matriglycans presented by the extracellular α-DG serve as a contact point with extracellular matrix proteins (ECM) containing laminin G-like domains, providing cellular stability. However, it remains unknown whether core M1 (GlcNAcβ1-2Man) structures can serve as ligands among the various O -Mannosylated glycans. Therefore, based on the presence of N -acetylLactosamine (LacNAc) in this glycan following the core extension, the binding interactions with adhesion/growth-regulatory galectins were explored. To elucidate this process, the interaction between galectin (Gal)-1, -3, -4 and -9 with α-DG fragment 372 TRGAIIQTPTLGPIQPTRV 390 core M1-based glycopeptide library were profiled, using glycan microarray and nuclear magnetic resonance studies. The binding of galectins was revealed irrespective of its modular architecture, adding galectins to the list of possible binding partners of α-DG core M1 glycoconjugates by cis -binding (via peptide- and carbohydrate-protein interactions), which can be abrogated by α2,3-sialylation of the LacNAc units. The LacNAc-terminated α-DG glycopeptide interact simultaneously with both the S- and F-faces of Gal-1, thereby inducing oligomerization. Furthermore, Gal-1 can trans-bridge α-DG core M1 structures and laminins, which proposed a possible mechanism by which Gal-1 ameliorates muscular dystrophies; however, this proposal warrants further investigation.

Supramolecular hydrogels formed by self-assembly of low-molecular-weight amphiphiles (hydrogelators) have attracted significant attention, as smart and soft materials. However, most of the observed stimuli-responsive behaviour of these supramolecular hydrogels are limited to gel–sol transitions. In this study, we present bola-amphiphilic glycosylated lipopeptide-type supramolecular hydrogelators that exhibit reversible thermochromism along with a gel–sol transition. The bola-amphiphiles have mono-, di-, tri- or tetra-phenylalanine (F) as a short peptide moiety. We investigate and discuss the effects of the number of F residues on the gelation ability and the morphology of the self-assembled nanostructures.

The first protecting group-free synthesis of N-glycosyl carbamates has been developed through reaction of Dglucose with n-butyl carbamate in acidic aqueous media. The structures of the N-glucosyl carbamates were unambiguously determined by comparison with authentic samples, prepared using the isocyanide method. With this protective group-free method for synthesis of N-glycosyl carbamates in hand, an anomeric pair of N-xylopyranosyl carbamates were prepared and used to assess the anomeric effect of nitrogen in the carbamate group.

Glucose is a key biomedical analyte, especially relevant to the management of diabetes. Current methods for glucose determination rely on the enzyme glucose oxidase, requiring specialist instrumentation and su ff ering from redox-active interferents. In a new approach, a powerful and highly selective achiral glucose receptor is mixed with a sample, L -glucose is added, and the induced CD spectrum is measured. The CD signal results from competition between the enantiomers, and is used to determine the D -glucose content. The involvement of L -glucose doubles the signal range from the CD spectrometer and allows sensitivity to be adjusted over a wide dynamic range. It also negates medium e ff ects, which must be equal for both enantiomers. The method has been demonstrated with human serum, pre- fi ltered to remove proteins, giving results which closely match the standard biochemical procedures, as well as a cell culture medium and a beer sample containing high (70 mM) and low (0.4 mM) glucose concentrations respectively.

We diversified the structures of bola-amphiphilic glycolipid-type supramolecular hydrogelators that exhibited reversible thermochromism along with a gel-sol transition. The hydrogelators were designed and synthesized to have homo- or hetero-saccharides on each end of their molecules. Herein, the effects of the saccharides' structure on the gelation ability are discussed.

Nanoemulsions (NEs) comprising Labrafac WC (R) as an inner oil and Cremophor (R) ELP as an outer surfactant are promising organic nanoparticles for biomedical applications due to their characteristics, such as a low toxicity, good structural robustness, and a high capacity to encapsulate hydrophobic contrasting agents or drugs. However, NEs present a limited ability to undertake surface functionalization, resulting in uncontrollable cellular uptake or the poor targeting of specific biomolecules and cells. To address this drawback, we herein developed the Cremophor (R) ELP-derivative (Crem-N-3), which possesses multiple azides. Remarkably, the surfaces of NEs formulated from Crem-N-3 were easily modified with dibenzocyclooctyne derivatives through a copper-free azide-alkyne cycloaddition reaction known as a bioorthogonal click reaction. Forster resonance energy transfer analysis revealed that these surface-modified NEs possess the desired dispersibility and integrity. Furthermore, NEs that were functionalized with a cell-penetrating peptide, namely octaalginine (R8), were rapidly internalized into cancer cells, unlike NEs containing no R8. Based on our results, we believe that NEs composed of Crem-N-3 as a cosurfactant are advanced NEs that allow flexible functionalization in response to targeted applications, such as vivo diagnostic applications that require a probe with minimum toxicity and specificity toward biological substances.