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Three new artificial transmembrane channel molecules have been designed and synthesized by attaching positively charged Arg-incorporated tripeptide chains to pillar[5]arene. Fluorescent and patch-clamp experiments revealed that voltage can drive the molecules to insert into and leave from a lipid bilayer and thus switch on and off the transport of K+ ions. One of the molecules was found to display antimicrobial activity toward Bacillus subtilis with half maximal inhibitory concentration (IC50) of 10 μ M which is comparable to that of natural channel-forming peptide alamethicin. [ABSTRACT FROM AUTHOR]

Three new artificial transmembrane channel molecules have been designed and synthesized by attaching positively charged Arg-incorporated tripeptide chains to pillar[5]arene. Fluorescent and patch-clamp experiments revealed that voltage can drive the molecules to insert into and leave from a lipid bilayer and thus switch on and off the transport of K+ ions. One of the molecules was found to display antimicrobial activity toward Bacillus subtilis with half maximal inhibitory concentration (IC50) of 10 μ M which is comparable to that of natural channel-forming peptide alamethicin. [ABSTRACT FROM AUTHOR]

The chemistry of imine bond formation from simple aldehyde and amine precursors is among the most powerful dynamic covalent chemistries employed for the construction of discrete molecular objects and extended molecular frameworks. The reversible nature of the C=N bond confers error-checking and proof-reading capabilities in the self-assembly process within a multi-component reaction system. This review highlights recent progress in the self-assembly of complex organic molecular architectures that are enabled by dynamic imine chemistry, including molecular containers with defined geometry and size, mechanically interlocked molecules, and extended frameworks and polymers, from building blocks with preprogrammed steric and electronic information. The functional aspects associated with the nanometer-scale features not only place these dynamically constructed nanostructures at the frontier of materials sciences, but also bring unprecedented opportunities for the discovery of new functional materials. This review highlights recent progresses in the self-assembly of complex organic molecular architectures that are enabled by dynamic imine chemistry, including molecular containers with defined geometry and size, mechanically interlocked molecules, and extended frameworks and polymers, from building blocks with preprogrammed steric and electronic information. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of three monomacrocycles and one bimacrocycle from two p-phenylene ethynylene frameworks. For two of the monomacrocycles, the two frameworks were linked by an amide unit and the macrocyclization involved the intramolecular formation of one imine bond. For another monomacrocycle and the bimacrocycle, the frameworks contained two and three amino or aldehyde units, respectively, and the macrocyclization involved the intermolecular formation of two and three imine bonds. [ABSTRACT FROM AUTHOR]

In this study, a series of H‐bonded arylamide foldamers bearing benzoselenadiazole ends with solvent‐responsive properties have been synthesized. In dichloromethane or dimethyl sulfoxide solvents, the molecules exhibit meniscus or linear structures, respectively, which can be attributed to the unique intramolecular hydrogen bonding behavior evidenced by 1D 1H NMR and 2D NOESY spectra. UV‐vis spectroscopy experiments show that the absorption wavelength of H‐bonded arylamide foldamers are significantly red‐shifted due to the presence of benzoselenadiazole group. In addition, the crystal structures reveal that effective intermolecular dual Se ⋅ ⋅ ⋅ N interactions between benzoselenadiazole groups induce further assembly of the monomers. Remarkably, supramolecular linear and double helices structures are constructed under the synergistic induction of intramolecular hydrogen bonding and intermolecular chalcogen bonding. Additionally, 2D DOSY diffusion spectra and theoretical modelling based on density functional theory (DFT) are performed to explore the persistence of intermolecular Se ⋅ ⋅ ⋅ N interactions beyond the crystalline state. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Actin filaments play important physiological functions, which have become potential targets of antitumor drugs. Using chemicals to intervene their polymerization‐depolymerization dynamics would generate new strategies for designing antitumor drugs. In this report, an artificial water channel appending acetazolamide moiety, a ligand that can selectively bind to carbonic anhydrase IX, has been prepared. We demonstrated that this conjugate can target colorectal cancer cells overexpressing carbonic anhydrase IX and trigger the depolymerization of actin filaments of the cancer cells by selectively mediating water transmembrane transport. Moreover, the conjugate‐promoted actin depolymerization led to tumor cell apoptosis and its high antitumor activity in vitro and in vivo against colorectal cancer. The method described herein represents a new and general strategy for designing antitumor drugs by using artificial channel‐mediated selective water transport to promote actin depolymerization. [ABSTRACT FROM AUTHOR]

Polypeptides, as natural polyelectrolytes, are assembled into tailored proteins to integrate chromophores and catalytic sites for photosynthesis. Mimicking nature to create the water‐soluble nanoassemblies from synthetic polyelectrolytes and photocatalytic molecular species for artificial photosynthesis is still rare. Here, we report the enhancement of the full‐spectrum solar‐light‐driven H2 production within a supramolecular system built by the co‐assembly of anionic metalloporphyrins with cationic polyelectrolytes in water. This supramolecular photocatalytic system achieves a H2 production rate of 793 and 685 μmol h−1 g−1 over 24 h with a combination of Mg or Zn porphyrin as photosensitizers and Cu porphyrin as a catalyst, which is more than 23 times higher than that of free molecular controls. With a photosensitizer to catalyst ratio of 10000 : 1, the highest H2 production rate of >51,700 μmol h−1 g−1 with a turnover number (TON) of >1,290 per molecular catalyst was achieved over 24 h irradiation. The hierarchical self‐assembly not only enhances photostability through forming ordered stackings of the metalloporphyrins but also facilitates both energy and electron transfer from antenna molecules to catalysts, and therefore promotes the photocatalysis. This study provides structural and mechanistic insights into the self‐assembly enhanced photostability and catalytic performance of supramolecular photocatalytic systems. [ABSTRACT FROM AUTHOR]

Polypeptides, as natural polyelectrolytes, are assembled into tailored proteins to integrate chromophores and catalytic sites for photosynthesis. Mimicking nature to create the water‐soluble nanoassemblies from synthetic polyelectrolytes and photocatalytic molecular species for artificial photosynthesis is still rare. Here, we report the enhancement of the full‐spectrum solar‐light‐driven H2 production within a supramolecular system built by the co‐assembly of anionic metalloporphyrins with cationic polyelectrolytes in water. This supramolecular photocatalytic system achieves a H2 production rate of 793 and 685 μmol h−1 g−1 over 24 h with a combination of Mg or Zn porphyrin as photosensitizers and Cu porphyrin as a catalyst, which is more than 23 times higher than that of free molecular controls. With a photosensitizer to catalyst ratio of 10000 : 1, the highest H2 production rate of >51,700 μmol h−1 g−1 with a turnover number (TON) of >1,290 per molecular catalyst was achieved over 24 h irradiation. The hierarchical self‐assembly not only enhances photostability through forming ordered stackings of the metalloporphyrins but also facilitates both energy and electron transfer from antenna molecules to catalysts, and therefore promotes the photocatalysis. This study provides structural and mechanistic insights into the self‐assembly enhanced photostability and catalytic performance of supramolecular photocatalytic systems. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry combines the strength of molecular assembly via various molecular interactions. Hydrogen bonding facilitated self-assembly with the advantages of directionality, specificity, reversibility, and strength is a promising approach for constructing advanced supramolecules. There are still some challenges in hydrogen bonding based supramolecular polymers, such as complexity originating from tautomerism of the molecular building modules, the assembly process, and structure versatility of building blocks. In this review, examples are selected to give insights into multiple hydrogen bonding driven emerging supramolecular architectures. We focus on chiral supramolecular assemblies, multiple hydrogen bonding modules as stimuli responsive sources, interpenetrating polymer networks, multiple hydrogen bonding assisted organic frameworks, supramolecular adhesives, energy dissipators, and quantitative analysis of nano-adhesion. The applications in biomedical materials are focused with detailed examples including drug design evolution for myotonic dystrophy, molecular assembly for advanced drug delivery, an indicator displacement strategy for DNA detection, tissue engineering, and self-assembly complexes as gene delivery vectors for gene transfection. In addition, insights into the current challenges and future perspectives of this field to propel the development of multiple hydrogen bonding facilitated supramolecular materials are proposed. [ABSTRACT FROM AUTHOR]

New acyclic cucurbit[n]urils (ACBs) with eight carboxylate groups were synthesized. These hosts are highly soluble in water, and can form stable inclusion complexes with cationic bitter compounds. ACBs are confirmed to be non‐toxic and biocompatible. Two‐bottle preference (TBP) tests on mice show that all ACBs are tasteless to mammals. ACBs are discovered to mask the bitterness of berberine and denatonium benzoate, but not quinine hydrochloride, due to different binding modes. [ABSTRACT FROM AUTHOR]

In this paper, two types of solid phase 2D and 3D XBOFs were selectively constructed from identical building blocks of tetraphenylmethane tetrapyridine derivative and 1,4-diiodotetrafluorobenzene by changing the crystallization solvent. This 3D XBOF is a novel hybrid supramolecular organic framework with the synergistic control of hydrogen and halogen bonds. [ABSTRACT FROM AUTHOR]

Review: [94 refs. [ABSTRACT FROM AUTHOR]

Conjugated polymers may be induced by intra- and/or intermolecular non-covalent forces to fold into helical conformations. Helices formed by aromatic amide, hydrazide, and urea polymers possess a well-organized cavity and depth, which is defined by their degree of polymerization. Driving forces may be intramolecular hydrogen bonding and/or solvophobicity, or guest induction. The resulting long helices represent a new class of unimacromolecular dynamic tubular architectures that exhibit unique properties or functions in, for example, molecular recognition, chirality transfer, and ion transporting. The recent advances are highlighted here. [ABSTRACT FROM AUTHOR]

Review: 215 refs. [ABSTRACT FROM AUTHOR]

Review: ca. 80 refs. [ABSTRACT FROM AUTHOR]

Review: 73 refs. [ABSTRACT FROM AUTHOR]

Chemotherapy is one of the main ways to treat breast cancer clinically. However, the multidrug resistance to anti-tumor drugs limits their clinical use. To overcome these drawbacks, development of drug delivery systems (DDSs) has attracted more and more attention in cancer therapy. At present, the preparation and purification process are complicated for many reported DDSs, while clinic calls for new DDSs that are more convenient for preparation. Here, a new pH-responsive supramolecular organic framework drug delivery complex loading doxorubicin (DOX) is fabricated. Anti-tumor activity of the system in vitro was investigated by cell cytotoxicity, uptake assay, and cell apoptosis analysis. The anti-tumor activity in vivo was investigated by inspecting nude mice body weight, tumor volume, and weight, also a preliminary mechanism probe was conducted by HE and TUNEL staining. The DOX@SOF displayed high stability, good biocompatibility, and pH regulated drug release. At acid condition, the hydrazone bonds would be broken, which result in the dissociation of SOF, and then the drugs would be released from the system. Furthermore, DOX@SOF enhanced cellular internalization. Both in vitro and in vivo experiments reflected that DOX@SOF could enhance the anti-tumor activity of DOX for the MCF-7/ADR tumor cells and tumors. This study provides a highly efficient strategy to prepare stimulus-responsive supramolecular drug delivery complex for treatment of drug-resistant cancer, the results presented inspiring scientific interests in exploring new drug delivery strategy and reversing multi-drug resistance for clinical chemotherapy. [ABSTRACT FROM AUTHOR]

A supramolecular organic framework‐type photocatalyst, named TM‐SOF, is constructed by the self‐assembly of cucurbit[8]uril and a tetra‐arm monomer containing four N, N'‐dimethyl 2,5‐bis(4‐pyridinium)thiazolo[5,4‐d]thiazole (MPT) moieties. Benefiting from the multivalent assembly, a photocatalytically active supramolecular MPT dimer can be stably formed in TM‐SOF. In addition, TM‐SOF exhibits better stability against temperature, substrate, and light irradiation. As a result, TM‐SOF shows a significantly improved performance for the photocatalytic aerobic oxidation of aryl boronic acids and thioethers. It is anticipated that this line of research will provide a facile approach for fabricating high‐performance supramolecular photocatalysis systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • A mesoporous 3D- fjh covalent organic framework is prepared and characterized. • Molecular chromophore and redox active components are incorporated into 3D COF. • Visible-light responsive and redox activity metal-free 3D COF photocatalyst. • Generation of reactive radical species to induce visible-light photoredox catalysis. • Highly efficient photoredox catalysis is demonstrated using 3D COF photocatalyst. Visible-light photoredox catalysis has been emerged as prominent methodology for efficient chemical synthesis. However, the relying use of soluble noble-metal photoredox catalysts suffer from long-term supply, inefficient separation, and could pos serious threats to the environment. Development of recyclable metal-free photoredox catalyst is thus highly significance. Herein, suitable molecular chromophore and redox units are condensed into photo- and redox active mesoporous 3D COF (3D TAPPy-TFPA) that enable highly efficient photoredox catalysis. The 3D COF displayed high crystallinity, mesoporous channel, and excellent structural stability. Optical and electrochemical studies revealed the excellent light harvesting, redox activity and effective generation of reactive radical species to induce photoredox catalysis. As proof-of-concept, 3D TAPPy-TFPA efficiently catalyzed the visible-light induced photoredox thiol-ene cross coupling and thiol radical mediated acylation of amines with activities surpassing most of the reported soluble photoredox catalysts. Beside recoverable, 3D TAPPy-TFPA showcased the previously inaccessible diacylation of amine into di-amide with high selectivity. This report shows robust design of outstanding and low-cost photoredox catalyst and paves the development of functional 3D COFs. [ABSTRACT FROM AUTHOR]

Selective preparation of two‐dimensional polymers (2DPs) and supramolecular polymers (2DSPs) with defined thickness is crucially important for controlling and maximizing their functions, yet it has remained as a synthetic challenge. In the past decade, several approaches have been developed to allow selective preparation of discrete monolayer 2DPs and 2DSPs. Recently, crystal exfoliation and self‐assembly strategies have been employed to successfully prepare bilayer 2DP and 2DSP, which represent the first step towards the controlled "growth" of 2D polymers from the thinnest monolayers to thicker few‐layers along the third dimension. This Concept review discusses the concept of accurate synthesis of 2D polymers with defined layers. Advances in this research area will pave the way to rational synthetic strategies for 2D polymers with controlled thickness. [ABSTRACT FROM AUTHOR]

Four compounds M1 , M2 , M3 , M4 , and one polymer P1 containing tetrathiafulvalene (TTF) units have been synthesized by the condensation of TTF-derived aldehyde and acylhydrazine precursors. UV–vis absorption and electron paramagnetic resonance spectroscopy as well as scanning electron microscopy reveal that the TTF + stacking of the polymer is considerably enhanced compared to that of the shorter compounds in polar solvents. [ABSTRACT FROM AUTHOR]

In host–guest chemistry, a larger hostmolecule selectivelyand noncovalently binds to a smaller guest molecule or ion. Earlystudies of host–guest chemistry focused on the recognitionof spherical metal or ammonium ions by macrocyclic hosts, such ascyclic crown ethers. In these systems, preorganization enables theirbinding sites to cooperatively contact and attract a guest. Althoughsome open-chain crown ether analogues possess similar, but generallylower, binding affinities, the design of acyclic molecular recognitionhosts has remained challenging. One of the most successful exampleswas rigid molecular tweezers, acyclic covalently bonded preorganizedhost molecules with open cavities that bind tightly as they stiffen. [ABSTRACT FROM AUTHOR]

Interestin two-dimensional (2D) polymers has increased rapidly since the isolationof graphene. However, approaches to the preparation of graphene-likematerials still face great challenges. Herein we report a facile methodto prepare single molecular thick 2D polymers by simply running thepolymerization reaction in a flask without the aid of any templatesand postmodification techniques. The strategy is to use the triptycenescaffold, a rigid three-dimensional skeleton, as one monomeric unitto substantially suppress the interlayer interaction between the as-formedpolymeric 2D monolayers. The new individual monolayered 2D polymersfloat freely in solution and can be further transferred onto solidsurface for characterization. It is also found that the resulting2D polymeric monolayers can further evolve into monolayered or multilayeredhollow spheres, which might be regarded as a model for the transformationof graphene to fullerene. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) have attracted increasing attention and emerged as a new research area in polymer chemistry. During the past decade, the intense desirability for application in aqueous scenarios has spawned the development of a specific class of POPs, i.e., water-soluble or dispersible porous organic polymers (WS-POPs) that can allow the implementation of porosity-based functions in aqueous media. In this Tutorial Review, aiming at providing a practical guide to this area, we will discuss recent advances in the preparation of WS-POPs through covalent/dynamic covalent, coordination and supramolecular approaches. As a result of their intrinsic and well-defined porosity, diverse topological architectures as well as unique water-processable features, many water-soluble/dispersible POPs have been demonstrated to exhibit potential for various applications, which include drug, DNA and protein delivery, bioimaging, photocatalysis, explosive detection and membrane separation. We will also highlight the related function of the representative structures. Finally, we provide our perspective for the future research, with a focus on the development of new structures and biofunctions. [ABSTRACT FROM AUTHOR]

Accurate control of the layer number of orderly stacked 2D polymers has been an unsettled challenge in self‐assembly. Herein we describe the fabrication of a bilayer 2D supramolecular organic framework from a monolayer 2D supramolecular organic framework in water by utilizing the cooperative coordination of a rod‐like bipyridine ligands to zinc porphyrin subunits of the monolayer network. The monolayer supramolecular framework is prepared from the co‐assembly of an octacationic zinc porphyrin monomer and cucurbit[8]uril (CB[8]) in water through CB[8]‐encapsulation‐promoted dimerization of 4‐phenylpyridiunium subunits that the zinc porphyrin monomer bear. The bilayer 2D supramolecular organic framework exhibits structural regularity in both solution and the solid state, which is characterized by synchrotron small‐angle X‐ray scattering and high‐resolution transmission electron microscopic techniques. Atomic force microscopic imaging confirms that the bilayer character of the 2D supramolecular organic framework can be realized selectively on the micrometer scale. [ABSTRACT FROM AUTHOR]

Accurate control of the layer number of orderly stacked 2D polymers has been an unsettled challenge in self‐assembly. Herein we describe the fabrication of a bilayer 2D supramolecular organic framework from a monolayer 2D supramolecular organic framework in water by utilizing the cooperative coordination of a rod‐like bipyridine ligands to zinc porphyrin subunits of the monolayer network. The monolayer supramolecular framework is prepared from the co‐assembly of an octacationic zinc porphyrin monomer and cucurbit[8]uril (CB[8]) in water through CB[8]‐encapsulation‐promoted dimerization of 4‐phenylpyridiunium subunits that the zinc porphyrin monomer bear. The bilayer 2D supramolecular organic framework exhibits structural regularity in both solution and the solid state, which is characterized by synchrotron small‐angle X‐ray scattering and high‐resolution transmission electron microscopic techniques. Atomic force microscopic imaging confirms that the bilayer character of the 2D supramolecular organic framework can be realized selectively on the micrometer scale. [ABSTRACT FROM AUTHOR]

Abstract: Dimesogenic compounds 1a–c, 2a–i, and 3, that are composed of a hydrogen bonding-induced straight arylamide spacer and two appended cholesterol groups, have been designed and synthesized. The backbones of the rigid spacers of 1a–c, 2a–i, and 3 contain one, three, and five benzene units, which bear two, six, and ten alkoxyl (methoxyl, n-octoxyl, or n-dodecoxyl) groups, respectively. The thermal and optical properties of the compounds are investigated by using the differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and powder X-ray diffraction (PXRD) analysis. It is revealed that 1a–c exhibit one or two liquid crystalline (LC) phases, 2a–i exhibit no, one or two LC phases, while 3 exhibits one LC phase in a wide temperature range. Generally, the more and longer alkoxyl chains facilitate the formation of the LC phases at low temperature. Notably, compound 2g, which bears two methoxyl and four dodecoxyl groups, displays a blue-red color change during both the heating and cooling cycle. The result illustrates that dimesogens with large rigid spacers can exhibit different LC phases when long aliphatic chains are appended to balance the strong stacking of the rigid backbones. [ABSTRACT FROM AUTHOR]

Abstract: This Letter reports the evidences for intramolecular six-membered N–H···O hydrogen bonding in N-benzyl benzamides and five-membered N–H···N hydrogen bonding in N-(pyridin-2-ylmethyl) benzamide. Intramolecular six-membered N–H···X (X=O or F) hydrogen bonding in 2-methoxyl- or 2-fluorobenzamides is used to lock the amide proton from forming strong intermolecular N–H···On bonding. As a result, for the first time the new intramolecular hydrogen bonding patterns are observed in the crystal structures of nine amides, whereas the whole molecules give rise to a new class of three-center hydrogen bonding motif. 1H NMR study in chloroform-d also supports that this weak intramolecular hydrogen bonding pattern exists in solution. [Copyright &y& Elsevier]

Abstract: The capacity of sulfur to form intramolecular five- or six-membered S⋯H–N hydrogen bonding in aromatic amides is assessed. The five-membered S⋯H–N hydrogen bonding is observed in crystal structures of five compounds, whereas the six-membered S⋯H–N hydrogen bonding is revealed in crystal structures of three compounds. The trityl group has been used to promote formation of the weak hydrogen bonding because it efficiently inhibits the competition of the intermolecular CH–N hydrogen bonding. (2D) 1H NMR experiments indicate that both patterns also exist in chloroform. [Copyright &y& Elsevier]

Abstract: Intramolecular three-centered hydrogen bonding has been used to induce dipyridyl anthranilamide 5 and diphenylacetylene anthranilamide 11 to adopt rigid straight conformation. Compound 5 reacted with Pd(dppp)(OTf)2 ( 12a ) or Pt(dppp)(OTf)2 ( 12b ) in dichloromethane to afford square metallocyclophanes 13a and 13b in 70% and 40% yield, respectively. In contrast, the reaction of 11 with 12b in dichloromethane gave triangular metallocyclophane 14 in 15% yield. [Copyright &y& Elsevier]

A novel, simple and versatile synthetic approach that utilized natural renewable low-toxic gallic acid as an organocatalyst was developed for efficient aerobic oxidative cross-cyclocondensations of equimolar 2-aminophenols and 2-hydroxylphenols to afford various 2-hydroxy-phenoxazin-3-ones with moderate to high isolated yields at room temperature in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photosensitizers incorporated into tetrahedral monomer efficiently avoid the aggregation. • Photosensitizer incorporated SOF provides increased stability, regularity, and catalytic activity. • SOF as a visible light photoredox catalyst exhibits good recyclability. Due to the urgent demand for environmentally friendly synthetic methods, metal-free materials have gained increasing prominence in various photocatalytic organic transformations. The utilization of supramolecular organic frameworks (SOFs) as photocatalysts has gradually emerged in photo-induced organic reactions, which complements the widespread use of porous organic polymers and covalent organic frameworks. SOFs, which are constructed through noncovalent interactions, can function as heterogeneous catalysts due to their low solubility in typical organic solvents. The present study reports the application of a SOF for heterogeneous photocatalysis. A tetraphenylmethane-based monomer (TM) incorporating four 4,4′-(thiazolo[5,4- d ]thiazole-2,5-diyl)bis(1-methyl-1-pyridinium) units (MPT) has been synthesized and co-assemble with cucurbit[8]uril (CB[8]) to afford a photoactive three-dimensional supramolecular organic framework (TM-SOF) through the encapsulation of two MPT units by CB[8]. Various methods have been employed to characterize the optical and electronic properties of TM-SOF and reveal its exceptional light-absorbing properties that facilitate photoredox catalysis by generating reactive radical species. As a heterogeneous photocatalyst, TM-SOF efficiently catalyzes photoinduced reductive dichlorination of α-chloroacetophenones and acetylation of amines with thioacetate with high recyclability. Mechanistic studies were further conducted to reveal the effect of the framework on the photocatalytic efficiency of the MPT unit. [ABSTRACT FROM AUTHOR]

A series of peptide-appended bisresorcinarenes were synthesized, which adopted tubular conformation induced by intramolecular hydrogen bonds. The derivatives formed unimolecular artificial transmembrane channels in lipid bilayers to enable selective transport of monovalent cations. Importantly, the channels exhibited reversible ligand-gating behavior in response to alkyl amine and Cu2+. [ABSTRACT FROM AUTHOR]

Different supramolecular self‐assembly between 1‐dodecyl‐3‐carboxymethylbenzotriazole (Lc12), 1‐octyl‐3‐carboxymethylbenzotriazole (Lc8) and 1‐butyl‐3‐carboxymethylbenzotriazole (Lc4) in the solid state and in aqueous solution has been investigated. For Lc12@CB[8] system, 1 : 1 host‐guest complexes were formed in aqueous solution and 2 : 2 host‐guest complexes were formed in the solid state, and the dodecyl chains adopted contorted conformations when bound to CB[8] molecules. For Lc8@CB[8] system, 1 : 1 host‐guest complexes were formed both in aqueous solution and in solid state, and the alkyl chain and benzotriazole moiety of guest Lc8 were both squeezed into the cavity of the CB[8]. The Lc4@CB[8] system was similar to Lc8@CB[8], 1 : 1 host‐guest complexes were formed in aqueous solution, the alkyl chain and benzotriazole moiety of guest Lc4 were encapsulated into the cavity of the CB[8]. Isothermal titrations in water afforded high apparent association constants for complexes Lc12@CB[8], Lc8@CB[8]and Lc4@CB[8]. [ABSTRACT FROM AUTHOR]

A novel strategy for the synthesis of cis‐decalins by an ytterbium‐catalyzed asymmetric inverse‐electron‐demand Diels–Alder reaction of 2‐pyrones and silyl cyclohexadienol ethers is reported here. A broad range of synthetically important cis‐decalin derivatives with multiple contiguous stereogenic centers and functionalities are obtained in good yields and stereoselectivities. A full set of diastereomeric substituted cis‐decalin motifs are readily accessible by tuning the absolute configurations of substituted silyl cyclohexadienol ethers (R or S) as well as the ligands (R or S). The synthetic potential is showcased by the enantioselective total synthesis of 4‐amorphen‐11‐ol, and further demonstrated by the first total synthesis of cis‐crotonin. [ABSTRACT FROM AUTHOR]

A novel strategy for the synthesis of cis‐decalins by an ytterbium‐catalyzed asymmetric inverse‐electron‐demand Diels–Alder reaction of 2‐pyrones and silyl cyclohexadienol ethers is reported here. A broad range of synthetically important cis‐decalin derivatives with multiple contiguous stereogenic centers and functionalities are obtained in good yields and stereoselectivities. A full set of diastereomeric substituted cis‐decalin motifs are readily accessible by tuning the absolute configurations of substituted silyl cyclohexadienol ethers (R or S) as well as the ligands (R or S). The synthetic potential is showcased by the enantioselective total synthesis of 4‐amorphen‐11‐ol, and further demonstrated by the first total synthesis of cis‐crotonin. [ABSTRACT FROM AUTHOR]

Water‐soluble three‐dimensional (3D) polymers are structurally ideal for the construction of ordered porous materials for in‐situ and tunable loading and release of guests. For many years, studies on ordered porous materials have been confined to crystalline solids. Since 2014, self‐assembly has been developed as a robust strategy for the preparation of water‐soluble 3D polymers that possess defined and intrinsic porosity. Through the encapsulation of cucurbit[8]uril for aromatic dimers, ordered diamondoid supramolecular organic frameworks can be assembled from tetrahedral monomers. With [Ru(bipy)3]2+‐derived octahedral complexes as precursors, cubic supramolecular metal‐organic frameworks have been assembled. One supramolecular organic framework has also been utilized to prepare the first homogeneous covalent organic framework through the [2+2] alkene cycloaddition, whereas the quantitative formation of the hydrazone bonds can be utilized to synthesize flexible porous organic frameworks. The new water‐soluble ordered and flexible polymeric frameworks are able to include drugs and biomacromolecules to accomplish in situ loading and intracellular delivery and to enrich photosensitizers and catalysts to enhance discrete visible light‐induced reactions. This review highlights the advances. [ABSTRACT FROM AUTHOR]

Inspired by arylamide-based oligomeric foldermers that are stabilized by intramolecular hydrogen bonding, a series of polyamides with intramolecular hydrogen-bonding motifs were synthesized viapolycondensation reactions. These polymers can fold into helical conformation different from their linear control. The chirality of helical conformation can further be tuned viaacid–base complexation using chiral residues. [ABSTRACT FROM AUTHOR]

Two rigid porous organic polymers (Ir-POP-1 and Ir-POP-2) were prepared from the coupling reactions of tetraphenylmethane tetraborate and two [Ir(ppy)2(dtbbpy)]+-based bitopic linkers and applied as heterogeneous visible-light photocatalysts for organic transformations. Ir-POP-2 was found to exhibit high catalytic activity for a wide range of organic reactions, which include Smiles–Truce rearrangement of alkyliodides, desulfurative conjugate addition to Michael acceptors, and aerobic oxidations of sulfides and arylboronic acids. For all the transformations, Ir-POP-2 could achieve heterogeneous photocatalytic efficiency that rivals that of the homogeneous prototype iridium complexes. This remarkably high photocatalytic performance has been attributed to the large pore size of the conjugated backbone. The new heterogeneous photocatalyst was also highly stable to achieve good recyclability for all the studied reactions and could be reused eight to nineteen times. [ABSTRACT FROM AUTHOR]

A new design concept for pH-sensing supramolecular fluorescent probes is reported. Supramolecular fluorescent pH probes based on pro-guest are designed and prepared. Pro-guests are designed to degrade under acidic condition and convert to competitive guests to displace encapsulated dyes, which leads to a significant enhancement in fluorescence intensity. A library of potential fluorescent pH probes is generated and screened to discover workable probes. These probes are capable of detecting the acidic pH in solution phase. We confirm that these supramolecular probes could detect the acidic environment in endosomal compartments in live cells. [Display omitted] • A new design concept to rapidly generate a large library of potential probes, which could be quickly screened. • The probes are based on commercially-available dyes. • Multiple probes could be discovered from a single library screening, which possess different photophyscial characteristics. [ABSTRACT FROM AUTHOR]

Two hydrogen-bonded 3-mer arylamide foldamers 1 and 2, which bear two pyridine or iodobenzene subunits at the ends, have been designed and prepared. Compound 1 co-assembles with 1,4-diiodotetrafluorobenzene (3) to form 2 + 2 macrocycles through four (py)N…I halogen bonds, whereas compound 2 dimerizes into a macrocycle through two C=O…I hydrogen bonds. Macrocycles formed by 1 and 3 stack to produce a supramolecular tube, with two neighboring macrocycles encapsulating one molecule of 3 through two C=O…I halogen bonds. Through such a cross-layer connection, formally the two molecules also give rise to a new halogen-bonded supramolecular helix, and further stack alternately to afford a double helix. In contrast, the mixture of 1 and fumaric acid (5) did not produce a similar encapsulation-derived helix, even though they also formed a halogen-bonded 2 + 2 supramolecular macrocycle. [ABSTRACT FROM AUTHOR]

Abstract Two new monofunctional mono-metallic trans -Pt(II)(salicylaldimine)(pyridine)·BF 4 (C1) and supramolecular dimetallic trans -(Pt(II)(salicylaldimine)) 2 (4,4-bipyridine)·2BF 4 (C2) complexes were designed and synthesized through ancillary chloride ligand exchange strategy and structurally characterized by spectroscopic, spectrophotometric and single crystal X-ray analyses. The solid-state structure analyses revealed interactions between the coordination planes, inter-molecular H-bonding, bonding in the ligand hydrogen and BF 4 anions and supramolecular interactions with solvent molecules in crystal packing. The in vitro anticancer effect of these complexes was investigated in breast (MCF-7) and liver (HepG2) cancer cells. Both these complexes showed significant anticancer effect comparable to cisplatin. Similarly, the effect of these complexes on Escherichia coli (E. coli) growth retardation was also analyzed and the results revealed stronger growth retardation effect and elongated morphology of bacterial cells in similar fashion as observed for cisplatin. The DNA interaction of C1 and C2 was investigated by gel electrophoresis using pET28 as target DNA. These complexes retarded migration of DNA across the gel showing their interaction with DNA. Graphical abstract Unlabelled Image Highlights • Monofunctional Pt(II) complexes synthesis and structure • Supramolecular Pt(II) complexes • Anticancer effect of monofunctional Pt(II) complexes • E. coli growth retardation and morphology • DNA interaction study by gel electrophoresis [ABSTRACT FROM AUTHOR]

Abstract The current study unveils ONS-donor ligand based Pt(II) complexes with unusual anticancer potency showing higher anticancer effect as compared to cisplatin. This series of Pt(II)(R-salicylaldimine)Cl (C1a-C4a) (R = 5-H, 5-CH 3 , F, 3-CH 3 O) complexes were prepared in single step in good isolated yields from commercially available materials. The chloride ancillary ligand of "a" series (C1a-C4a) was replaced with 4-picoline and "b" series of four complexes Pt(II)(R-salicylaldimine)(4-picoline)BF 4 (C1b-C4b) (R = 5-H, 5-CH 3 , F, 3-CH 3 O) was obtained. All these complexes were characterized by different structure elucidation techniques. Among these, the structures of C1a , C2a , C2b and C3b were determined in solid state by single crystal X-ray analysis. We found quick aquation of "a" series of complexes in DMSO/water mixture that was well investigated by 1H NMNR, LCMS and ESI-MS, while "b" series of these complexes was quite stable over a month as described by the 1H NMNR in DMSO/D 2 O mixture. This ONS-donor ligand based class of Pt(II) complexes showed unusual anticancer potency in non-small cell lung cancer A549, colorectal cancer HT-29 and triple negative breast cancer MDA-MB-231 cells. These Pt(II) complexes induced PARP cleavage and significantly inhibited colony formation ability of cancer cells. Mechanistically, we found reduced aggressive growth of cancer cells by the induction of autophagic cell death via LC3-I/LC3-II expression and recruitment of LC3B to autophagosomal membrane. These complexes induced p21 expression, that suggested their potentials to suppress cell cycle progression. Significant activation of Caspase3/7-dependent apoptotic signaling was observed in cancer cells treated with these Pt(II) complexes. Morphological changes of cancer cells suggested their potentials to modulate epithelial-mesenchymal-transition (EMT) like features of cancer cells. Gel electrophoresis study revealed their interaction with plasmid DNA. Similarly, strong growth retardation effect and filamentous morphology was observed in Escherichia coli (E. coli). These ONS-donor Pt(II) complexes possessed strong anticancer effect in multiple human cancer cells via activation of multiple pathways for apoptotic and autophagic cell death. Graphical abstract Image 1 Highlights • ONS-donor Pt(II) complexes synthesis and structure study. • Aquation and stability of Pt(II) complexes. • Apoptosis via multiple genes activation pathways. • Autophagy induction. • E. coli growth retardation and filamentous morphology. [ABSTRACT FROM AUTHOR]

Halogen bonding has been used to glue together hydrogen‐bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2I or fluorinated iodobenzene group at the other end, engage in head‐to‐tail N⋅⋅⋅I halogen bonds to form one‐component supramolecular P and M helices, which stack to afford supramolecular double‐stranded helices. One of the double helices can dimerize to form a G‐quadruplex‐like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2CF2I through N⋅⋅⋅I halogen bonds to form two‐component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine‐bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine‐bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two‐dimensional space. Glued in place: Halogen bonds glue together short hydrogen‐bonded arylamide molecules to form either one‐ or two‐component helices. The helices stack to produce supramolecular quadruple and double helical structures. [ABSTRACT FROM AUTHOR]

Halogen bonding has been used to glue together hydrogen‐bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2I or fluorinated iodobenzene group at the other end, engage in head‐to‐tail N⋅⋅⋅I halogen bonds to form one‐component supramolecular P and M helices, which stack to afford supramolecular double‐stranded helices. One of the double helices can dimerize to form a G‐quadruplex‐like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2CF2I through N⋅⋅⋅I halogen bonds to form two‐component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine‐bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine‐bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two‐dimensional space. [ABSTRACT FROM AUTHOR]

Abstract 42 members supramolecular macrocycle (H 4 M) was synthesized in a simple one-step 2 + 2 condensation of 2,5‑diformyl hydroquinone with 4,7,10‑trioxa‑1,13‑tridecanediamine. The macrocycle was isolated in good yield by simple filtration and washing from the final reaction mixture. H 4 M has multiple salicylaldimine ON-donor sockets in the aromatic salicylaldimine part and six "O" atoms in ethylene glycol chains for transition or alkali metals or other cationic species binding. Preliminarily, this macrocycle was used in the synthesis of trans -tetra-platinum mono-chloride mixed ligand complex (M-4Pt(pyridine)Cl). The UV–vis analysis of this complex showed characteristic absorption around λ max = 593 nm visible region. Similarly a dimetallic quinone bridged control complex L-2Pt(pyridine)Cl bearing two Pt metals was prepared to better understand the structural orientation of the supramolecular macrocyclic complex (M-4Pt(pyridine)Cl). The structure of this control complex was determined by single crystal X-ray. Comparative UV analysis of M-4Pt(pyridine)Cl and L-2Pt(pyridine)Cl showed that the absorption of the same concentration of tetra-metallic macrocyclic complex was more than two times (ɛ = 7.0 × 10−3 mol−1 cm−1) to that observed for dimetallic control complex (ɛ = 3.1 × 10−3 mol−1 cm−1). The extremely simple productive synthetic and isolation procedure and the presence of multiple donor atoms promises to make this macrocycle an appealing platform in organometallic and supramolecular chemistry. Graphical abstract A 2 + 2 supramolecular 42 members macrocycle (H4M) was synthesized in a simple one step reaction in good isolated yield from commercially available precursors. This macrocycle was used in the synthesis of trans-tetra‑platinum chloride mixed ligand complex (M-4Pt(pyridine)Cl) having characteristic UV–vis absorption in visible region λ max = 593 nm. The extremely simple synthetic procedure and the presence of multiple donor atoms, promises to make this macrocycle an appealing platform in organometallic and supramolecular chemistry. Unlabelled Image Highlights • 42 members supramolecular macrocycle • Simple one step route for the synthesis of multi-functional macrocycle • Tetra-metallic Pt(II) complex • Enhance visible region absorption of multi-metal based Pt(II) complex • Solid state structure of quinone-bridged Pt(II) complex [ABSTRACT FROM AUTHOR]

A new acylhydrazone fluorescence probe, SPBH, was synthesized from salicylaldehyde and 4-(pyridin-4-yl)benzohydrazide (PBH). SPBH exhibited high selectivity and a sensitive fluorescence response towards Al3+, even in the presence of other competing metal ions in DMF/H2O (1 : 1, v/v) medium. And, the chemosensor can even detect Al3+ in the intracellular region of human non-small cell lung cancer H460 cells. The binding phenomenon of SPBH was investigated by 1H NMR spectroscopy and HR-MS. Mass spectrometry analysis showed a 1 : 1 complex formation of SPBH with Al3+. The Job plot also confirmed its 1 : 1 interaction. This SPBH/Al3+ complex exhibited excellent fluorescence “turn-off” properties towards the F− anion. Thus, SPBH acts as a sequential fluorescence “Off–On–Off” probe. The limits of detection for Al3+ and F− were calculated from the titration curve and found to be 1.1 × 10−7 M and 1.47 × 10−6 M, respectively. [ABSTRACT FROM AUTHOR]

Abstract A series of bis-salicylaldimine ligands bearing two ON-donor functions were reacted with dichloro(p -cymene)ruthenium(II) dimer in the presence of base (NaOAc) and a series of four dimetallic Ru(II) arene complexes (Ru(p -cymene)) 2 (bis-salicylaldimine)Cl 2 (C1 C4) were prepared. These complexes were obtained in excellent isolated yields and characterized in detail by using different spectroscopic techniques. The structure of C1 was also determined in solid state by single crystal X-ray analysis. These complexes were studied for their cytotoxic effect against three different types of human cancer cells including hepatocellular carcinoma (HepG2), non-small-cell lung cancer (A549) and breast cancer (MCF-7) cells by MTT assay. These complexes showed considerable cytotoxic effect in all the above-mentioned cell lines that was comparable to the effect of cisplatin. C1 and C2 showed moderate anticancer effect while C3 and C4 showed reasonable cytotoxicity. We found the cytotoxicity was increased in series from C1 to C4 representing the effect of ligand modification from small to bulky group at the amine functionality of the salicylaldimine. We selected C3 and C4 for mechanistic anticancer study in MCF-7 cells. The acridine orange/ethidium bromide and DAPI staining assays of MCF-7 cells treated with Ru(II) complexes showed apoptosis in cancer cells. Similarly, these complexes induced p53 protein expression in MCF-7 cells. Further, increased mRNA levels of p63, p73, PUMA, BAX and NOXA genes were observed in response to the treatment with C3 and C4 , while cyclinD1, MMP3 and ID1 gene expression was significantly reduced. We found reduced invasion ability in breast cancer cells treated with C3 and C4. Taken together, we demonstrated that bis-salicylaldimine based dimetallic Ru-(p -cymene) complexes exerts anticancer effects by p53 pathway, suggesting the promising chemotherapeutic potentials of these Ru(II) complexes for the treatment of cancer. This study may further pave for their in depth in vitro or in vivo anticancer investigations. Graphical abstract Dimetallic bis-salicylaldimine based Ru(II) arene complexes (Ru (p-cymene))2 (bis-salicylaldime)Cl2 were prepared and investigated as anticancer agents. Their in vitro cytotoxic effect on cancer cells was comparable to cisplatin. They induced p53, p63 and p73 genes expression and regulated PUMA, BAX and NOXA genes in MCF-7 breast cancer cells. Image 1 Highlights • Dimetallic ruthenium complexes. • Single crystal X-ray structure characterization. • Anticancer study of Ru(II) arene complexes. • Genes activation for efficient apoptosis in cancer cell. • p53 activation by Ru(II) complexes. [ABSTRACT FROM AUTHOR]