Themed collection Supramolecular chemistry in OBC

This paper presents an overview of synthetic approaches for fluorene-based cyclic compounds by examining four different connection models of fluorenes, involving 2,7-, 3,6-, 9,9-, and 2,9-linked patterns.

In this review, recent researches on triptycene-based macrocyclic arenes, organic cages, porous materials and TADF materials are summarized.

This review compiles selected relevant examples of synthetic receptors defining a closed three-dimensional cavity (cages) with applications in chemical biology and biomedicine.

This review lays emphasis on background concept and summarizes the recent developments of various competitive IDAs. Moreover, current challenges relating to the development of new IDAs and potential future perspectives revealing the fate of IDAs have also been given.

This review features the recent advancement made in phosphorus-containing POPs, highlighting different synthetic techniques for their preparation and application in organic synthesis.

In this review, we will fully discuss the synthesis/preparation and applications of crown ether–pillararene hybrid macrocyclic systems/compounds.

This review outlines challenges faced in recognition and detection of dicarboxylic acids and dicarboxylates and strategies used to obtain effective and observable interactions in the period from 2014 to 2020.

Synthetic methodologies towards the preparation of oligomeric and polymeric mechanically interlocked molecules are described, including both covalent strategies and self-assembly approaches.

Recent progress regarding the combination of porphyrins and pillararenes into hybrid compounds and supramolecular systems is summarized in this review.

This review summarizes recent developments in visible-light enantioselective photocatalysis reactions, which provide convenient and effective tools for asymmetric synthesis.

The emergence and applications of the C–H activation logic as a new paradigm in macrocyclization reactions are captured in this review.

The following review gives an overview about synthetic peptide–polymer conjugates as macromolecular building blocks and their self-assembly into a variety of supramolecular architectures, from supramolecular polymer chains, to anisotropic 1D arrays, 2D layers, and more complex 3D networks.

The chemistry of tetrathiafulvalene-calix[4]pyrrole is reviewed with focus on conformational behavior, receptor properties and ionically controlled electron transfer processes.

Recent progress in supramolecular vesicles based on pillar[n]arenes is reviewed.

28π antiaromatic macrocycles with benzene and azulene units and their effects on local and global (anti)aromaticity have been described. Experimental and computaionl studies confirmed strong diatropic ring current effects in their dicationic states, respectively.

Supramolecular bis(cholyl) ion channels with oxalamide and hydrazide as selectivity filters are reported. The hydrazide system showed superior chloride transport activity to oxalamide due to better anion recognition.

Multiply-carbonylated fullerene derivatives were found to work as one component in frustrated Lewis pairs which caused an Si–H bond activation in the presence of B(C₆F₅)₃, leading to the carbonyl hydrogenation in up to 99% yield.

Lactamisation of phenol-ester activated peptide esters is promoted by supramolecular Zn-TPP complex formation.

Through a combined crystallographic and computational analysis, we designed and investigated two novel host units for the recognition of neutral and charged guests inspired by a glutamate carboxypeptidase II system and its inhibitors.

The properties of three imidazolium based ionic liquids have been compared and used as solvents for the electrochemical oxidation of various anions.

Short lipopeptides, that self-assemble into supramolecular structures, show antimicrobial activity.

Liposomes equipped at the outer membrane with positively charged calixarenes show improved efficiency in cargo delivery. This is facilitated by the interaction between the macrocycle units and heparan sulfate proteoglycans surrounding the cell.

Isophthalamide (X = CH) and a dipicolinamide (X = N) derived dipyridyl ligands both form a [Pd₂L₄][BF₄]₄ cage in solution, but only the isophthalamide derived cage easily binds to glycosides and nitrate.

Supramolecular M- and P-helices are formed via intermolecular S⋯S and S⋯O chalcogen bonding of alanine-based azapeptides containing a β-turn structure and equipped with a thiophene group at the N- or C-terminus, respectively.

The encapsulation of discrete water molecules in flexible sheet-like aromatic oligoamide foldamers, as evidenced by structural and spectroscopic studies, stabilizes their structure.

A single substitution on p-sulfonatocalix[4]arene, away from its binding face, modifies its selectivity towards a smaller and less hydrophobic guest (dimethyllysine) without making direct contact with the guest.

A convenient approach for the synthesis of foldable redox-active flavin peptide conjugates was established.

The self-assembly of an A1/A2 disubstituted pillar[5]arene was used to construct a supramolecular brush polymer.

A Mukaiyama aldol reaction can be catalyzed by bidentate halogen bond donors with very high efficiency. The halogenated catalysts were stable over multiple consecutive runs, which supports the halogen-bond-based mode of catalysis.

We designed and synthesized a library of cryptand-like structures on the T7 phage; a strong binder for a cancer-related protein was selected from the library.

The aptameric protective group strategy is compatible with diverse reagents and reaction conditions for the synthesis of new neomycin B derivatives.

N-TIPS pyrrole and thiophene/selenophene dicarbinol: the two most promising and significant building blocks made for each other for constructing highly aromatic and NIR absorptive trans-doubly N-confused porphyrins.

Appendage of an amphiphilic chain by exploiting the nitrogen installed on the 6-aza-artemisinin imparted self-assembling properties. The fully synthetic 6-aza-artemisinin formed aggregates and exhibited increased in vitro anti-cancer activities.

We report a deprotection-induced aromaticity switching from nonaromatic to a 22π aromatic macrocycle of 3-oxypyripentaphyrin(0.1.1.1.0) with strong NIR absorption.

The elusive flavin semiquinone intermediate found in flavoproteins such as cryptochromes has been obtained in aqueous solution by single electron reduction of the natural FMN cofactor using sodium ascorbate.

Inversion of the amide connectivity of an azobenzene dyad, which self-assembles into chiral toroids and nanotubes, improves the thermal stability of the assemblies, however it negatively affects supramolecular chirality.

The investigation into the self-assembly formation of the glycan based 4-amino- and 4-bromo-1,8-naphthalimide (Nap) structures 1–3 is presented.

π-Conjugation patterns determine the association strengths of purine and pteridine quartets.

In contrast to sulfonato-calix[4]arene (sclx₄), which mediates close-packed assemblies, the higher charge carboxylate-containing sclx₄mc induced a crystalline framework of cytochrome c.

Single-handed quinoline oligoamide foldamer-based bisphosphine ligands that can coordinate with Rh(cod)₂BF₄ were used as a platform in asymmetric hydrogenation.

Asymmetric allylation of aldehydes was conducted inside the helical cavity of a helically folded π-conjugated polymer bearing pyridine N-oxide pendants.

For the first time the formation of hexameric pyridine[4]arene capsule has been observed in gas phase, in solution and in solid state. A thermodynamic balance between capsule formation was observed, showing favour to hexamer.

The synthesis of fluorene-based 3D-grid-FTPA, which shows excellent chemical, thermal, and photo-stabilities, has been developed using a one-pot Friedel–Crafts reaction.

meso-Aryl substituted highly stable single conformers of doubly mutant porphodimethenes.

Unidirectional binding between a pillar[4]arene[1]benzoquinoneoxime host and n-alkyl alcoholic guests was realized with the hydroxy heads of the guests in direct contact with the oxime group of the macrocyclic host.

Acid/base and base/acid-controllable molecular switches were constructed based on water-soluble anionic pillar[6]arene or cationic pillar[6]arene and a viologen ditosylate salt.

Upon protonation, a tren-capped hexaphyrin undergoes simple conformational exchanges between rectangular, Möbius and triangular shapes affording different aromaticities and cage environments, and ultimately leading to a host–guest complex.

Molecules that assemble through reversible covalent and noncovalent interactions achieve self-assembly at extreme levels of urea and NaCl.

A prodrug is encapsulated in CB[7] and is photochemically transformed into an active drug inside this supramolecular complex.

Photoexcitation of dibenzalacetones in homogeneous media and solid state yields a mixture of products with poor conversions. Reactivity of the substrate encapsulated within γ-cyclodextrin results in efficient 2 + 2 photocycloaddition between two reactants on both alkenes groups, yielding a single product with remarkable regio- and stereoselectivity at high conversions.

A hydrogen bonded luminescent supramolecular network from HTPE and CTPE can be further tuned.

Molecular tweezers using aromatic interactions for binding normally work best in polar instead of nonpolar solvents due to the strong solvophobic effect in the binding.

Chemical reactions in a confined nanospace can be very different from those in solution.

Intramolecularly enhanced flexible receptors outperformed traditional rigid receptors when the direct binding force was weakened by solvent competition.

Narcissistic chiral self-sorting prevailed in the assembly of molecular face-rotating polyhedra from a C_3h building block 5,5,10,10,15,15-hexabutyl-truxene-2,7,12-tricarbaldehyde and racemic mixtures of 1,2-diamines.

Large Co(II)-induced VCD signals provide a method for determining the enantiomeric excess of α-amino acids. This strategy can be followed for building new VCD protocols.

Various small molecules containing boronic acid and urea functionalities are shown to bind selectively to the bacterial lipid PG (phosphatidylglycerol) and exert antibacterial activity through a membrane-related mechanism.

Dendronization by click chemistry as a tool to improve the physicochemical properties of bioactive organic molecules toward biological applications.

Two positive charges generated by oxidation of a monopyrrolotetrathiafulvalene unit (green) raise an electrostatic barrier to decrease the speed of the deslipping of a tetracationic ring (blue) that take place in a [2]pseudorotaxane.

All 4 + 4 diastereomeric amine macrocycles derived from trans-1,2-diaminocyclopentane and 2,6-difromylpyridine have been synthesized. Chiral compounds exhibit chiral resolution towards 10-camphorsulfonic and tartaric acids.

The high enantioselective arylation was pseudo-biologically accererated by self-inclusion of the Rh complex bearing a γ-cyclodextrin.

We present a new luminescent europium(III)-based anion receptor that binds to PAP (adenosine-3′,5′-diphosphate). The increased emission intensity and lifetime of the receptor-PAP complex was used to develop the first real-time assay of heparan sulfotransferase activity.

Self-assembled/self-sorted hetero dimer capsules consisting of pairs of two- and four-armed porphyrins were constructed. Small and large aromatic guests were selectively recognized by two- and four-armed dimers, respectively.

π-face masking opens up a new pathway to control the location of acceptor along the donor backbone and consequently donor–acceptor binding interaction strength and percentage of acceptor ionization.

A fuel driven control of the shape and geometry of the calix[4]arene scaffold allows ON/OFF/ON dissipative fluorescence cycles.

Diamond-type nanogrids (DGs), can helically expand to form spiro-linked polymers. Herein, we designed and synthesized two types of DGs, DGs-1 (A₁B₁ mode) in 44–50% yields, and DGs-2 (A₂ + B₂ mode) in 64% yield.

The synthesis of four 2,6-bis(1,2,3-triazol-4-yl)pyridine(btp) olefin based ligands 3, 4, 11 and 12 is described and their formation of macrocyclic products using ring closing metatheses (RCM) reactions rather than mechanically interlocked molecules.

An efficient gold-catalyzed oxidative cyclization of amide-alkynes for the synthesis of functionalized γ-lactams is described.

The acridinone 1,9-bis(thio)urea scaffold was repurposed for application in anion transport by appending a variety of electron-withdrawing groups to the peripheral phenyl moieties. High levels of activity were achieved which facilitated strictly electroneutral transport.

We present a strategy for characterising and preventing the undesired folding between adjacent units in duplex-forming synthetic hetero-oligomers.