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Three decades after A. P. de Silva's seminal paper introduced the concept of logic gates at the molecular level, the field of molecular logic gates (MLGs) has witnessed significant advancements. MLGs are devices designed to perform logical operations, utilizing one or more physical or chemical stimulus signals (inputs) to generate an output response. Notably, MLGs have found diverse applications, with optical detection of analytes emerging as a notable evolution of traditional chemosensors. Organic synthesis methods are pivotal in crafting molecular architectures tailored as optical devices capable of analyte detection through logical functions. This review delves into the fundamental aspects and physical–chemical properties of MLGs, with a particular emphasis on synthetic strategies driving their design. [ABSTRACT FROM AUTHOR]

The construction of diverse and distinctive self‐assembled structures in water, based on the control of the self‐assembly processes of artificial small molecules, has received considerable attention in supramolecular chemistry. Cage‐like perforated vesicles are distinctive and interesting self‐assembled structures. However, the development of self‐assembling molecules that can easily form perforated vesicles remains challenging. This paper reports a lower critical solution temperature (LCST) behavior‐triggered self‐assembly property of a 4‐aminoquinoline (4‐AQ)‐based amphiphile with a tetra(ethylene glycol) chain, in HEPES buffer (pH 7.4). This property allows to form perforated vesicles after heating at 80 °C (> LCST). The self‐assembly process of the 4‐AQ amphiphile can be controlled by heating at 80 °C (> LCST) or 60 °C (< LCST). After cooling to room temperature, the selective construction of the perforated vesicles and nanofibers was achieved from the same 4‐AQ amphiphile. Furthermore, the perforated vesicles exhibited slow morphological transformation into intertwined‐like nanofibers but were easily restored by brief heating above the LCST. [ABSTRACT FROM AUTHOR]

Coordination supramolecular chemistry provides a versatile entry into materials with functionalities of technological relevance at the nanoscale. Here, we describe how two different bis-pyrazolylpyridine ligands (L1 and L2) assemble with Co(II) ions into dinuclear triple-stranded helicates, in turn, encapsulating different anionic guests. These constructs are described as (Cl@[Co2(L1)3])3+, (SiF6@[Co2(L1)(L2)3])2+ and (ClO4@[Co2(L2)3])3+, as established by single-crystal X-ray diffraction. Extensive magnetic and calorimetric measurements, numerical treatments and theoretical calculations reveal that the individual Co(II) centers of these supramolecular entities exhibit field-induced slow relaxation of magnetization, dominated by direct and Raman mechanisms. While the small variations in the spin dynamics are not easily correlated with the evident structural differences among the three species, the specific heat measurements suggest two vibronic pathways of magnetic relaxation: one that would be associated with the host lattice and another linked with the guest. [ABSTRACT FROM AUTHOR]

This paper presents an efficient and practical protocol for the synthesis of rufinamide (anti-epileptic drugs) active pharmaceutical ingredient (API) and several process impurities by a 1,3-dipolar cycloaddition reaction, starting from commercially available benzyl bromides. The earlier reported syntheses of rufinamide had encountered challenges in isolating by-products from the mother liquor. In this work, the impurities were synthesized via the retrosynthesis route to serve as reference samples for assessing the purity level of drugs. These impurities, characterized by the presence of N-group and azole derivatives, find wide-range applications in academic and industrial settings, including organic synthesis, drug discovery, polymer chemistry, chemical biology, and supramolecular chemistry. The primary objective of this synthesis was to propose a reliable and pragmatic method for producing rufinamide and its impurities to address diverse scientific and industrial requirements. The protocol outlined in this research aims to contribute to the development of robust methodologies for the synthesis of pharmaceuticals and associated impurities, with potential implications for drug development and chemical research. [ABSTRACT FROM AUTHOR]

A series of fifteen tetravalent thorium phases were prepared. The compounds were isolated from acidic aqueous nitrate solutions using protonated nitrogen heterocycles of varying hydrogen-bond donation strength. Structural analysis via single crystal X-ray diffraction showed that the structures are built from pentanitrato, [Th(NO3)5(H2O)2]1−, and hexanitrato, [Th(NO3)6]2−, molecular units, with the latter being far more prevalent in the solid state. The vibrational properties of the compounds were examined using Raman and IR spectroscopy; the spectra are dominated by stretches characteristic of nitrate and the organic ions. The relative energetics of nitrate complexation was examined using electronic structure theory. These results confirmed that there are clear thermodynamic sinks for the penta- and hexanitrato structural units that were observed experimentally. Additionally, electrostatic surface potentials (ESPs) were calculated in an effort to better understand the counterion stabilization of the complexes. The ESP surfaces showed that the position of the water and nitrate molecules and the coordination geometry of the metal complex had a clear effect on the polarizability of the two structural motifs. Despite limited speciation of the Th–nitrate structural units, the compounds exhibit rich supramolecular chemistry resulting from hydrogen bonding of the Th complexes with the organic N–H donors and π–π stacking interactions from the protonated N-heterocycles. [ABSTRACT FROM AUTHOR]

The use of hierarchically structured materials as catalysts has been finding increasing application in the past years. For these catalytic systems, not only the nano‐scale matters: a high degree of order across multiple length scales, along with its control and analytical assessment, is of paramount importance to obtain innovative properties that can find application in catalysis. Most reviews dealing with hierarchically structured materials are concerned with the "bottom‐up" transfer of structural information along the different length scales, with special emphasis on the transmission of chirality. Due to their mesoscale size together with their complex behaviour, these systems are often susceptible to feel the effects of macroscopic forces, that can exert a "top‐down" control of their catalytic properties, so that an external stimulus, acting at the level of the supramolecular architecture of the catalyst, can ultimately determine the outcome of the catalyzed reaction at the molecular level. We review in this paper some recent reports that deal with the experimental implementation of this concept, either by using a mechanical force in a full range direct transmission to the reaction coordinate, or by means of a stepwise relay transmission from the macroscopic level (purely supramolecular chirality) to the nanoscopic one. We focus in this review on these multi‐length scale communication control effects, identifying the different mechanisms that are affecting the catalytic activity. [ABSTRACT FROM AUTHOR]

This paper investigates the structural properties of 2,5‐bis(3‐bromophenyl)furan polymorphs, focusing on the halogen interactions and their influence on crystal mechanical properties. In this study, three different polymorphic modifications were obtained which crystallize in the orthorhombic system. Two of the polymorphs possess halogen interactions but only one exhibits elastic properties. Through X‐ray diffraction, crystallographic analysis and computational modelling, intricate bromine‐based halogen interactions and their impact on the packing arrangement and stability were revealed. The correlation between these interactions and crystal properties, including molecular arrangement and intermolecular forces, is explored. Understanding these relationships is vital for materials design and supramolecular chemistry, enabling the rational synthesis of tailored materials. [ABSTRACT FROM AUTHOR]

The controllable synthesis of non-classical nucleobase pairs that can mimic partial biological behavior is very important for the in-depth study of DNA or RNA. Here, three different interaction modes of uracil–uracil base pairs (U-motif) have been explored in the coordination complexes of 2′-deoxyuracil 5′-monophosphate (dUMP) and uracil 5′-monophosphate (UMP) with transition metal ions by single crystal structural analysis and DFT calculations for the first time. The results indicate that the structural diversity of non-classical nucleobase pairs may be a bank of supramolecular interactions, which will contribute to the study of supramolecular chemistry and biochemistry. [ABSTRACT FROM AUTHOR]

The development of efficient methods for the synthesis of mechanically interlocked compounds is currently considered a major challenge in supramolecular chemistry. Twofold vinylogous fumaramides, a class of conjugated bis(enaminones), successfully achieve the assembly of hydrogen-bonded amide-based rotaxanes, with a templating ability comparable to that of their parent fumaramide-based systems, showcasing full conversions and impressive yields up to 92%. Computational calculations offer a compelling explanation for the remarkable efficiency of these bis(enaminones) in driving the synthesis of unprecedented rotaxanes. The reactivity of these interlocked species was thoroughly investigated, revealing that a one-step double stopper-exchange process can be successfully performed while preserving the mechanical bond. This approach facilitates the formation of controllable rotaxanes, including a three-station molecular shuttle, whose assembly via a clipping methodology is highly unselective. The internal translational motion of this latter species has been successfully controlled in a reversible way by means of a cycloaddition/retrocycloaddition sequence. Many templates for accessing hydrogen-bonded amide-based rotaxanes have resulted in modest yields, but a novel templating method has shown significant promise. Conjugated bis(enaminones) serve as an effective template for the formation of rotaxanes, and a post-synthetic double stopper-exchange method further enables the preparation of versatile and complex rotaxane structures. [ABSTRACT FROM AUTHOR]

Light-driven rotary molecular motors are among the most promising classes of responsive molecular machines and take advantage of their intrinsic chirality which governs unidirectional rotation. As a consequence of their dynamic function, they receive considerable interest in the areas of supramolecular chemistry, asymmetric catalysis and responsive materials. Among the emerging classes of responsive photochromic molecules, multistate first-generation molecular motors driven by benign visible light remain unexplored, which limits the exploitation of the full potential of these mechanical light-powered systems. Herein, we describe a series of all-visible-light-driven first-generation molecular motors based on the salicylidene Schiff base functionality. Remarkable redshifts up to 100 nm in absorption are achieved compared to conventional first-generation motor structures. Taking advantage of all-visible-light-driven multistate motor scaffolds, adaptive behaviour is found as well, and potential application in multistate photoluminescence is demonstrated. These functional visible-light-responsive motors will likely stimulate the design and synthesis of more sophisticated nanomachinery with a myriad of future applications in powering dynamic systems. First-generation light-driven rotary molecular motors received considerable interest in various areas of chemistry, but those driven by benign visible light remain less explored. Here the authors describe all-visible-light-driven first-generation molecular motors which show an adaptive behaviour and explore application in multistate photoluminescence. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry encompasses critical aspects found throughout the chemical sciences. Despite its ubiquity, the concept of supramolecular chemistry as a defined field of research is relatively young, although its roots run deep. Moving from strength to strength, the Royal Society of Chemistry’s MASC meeting has grown from a local, UK-based conference to a truly international event. The 2023 edition of MASC was held at the University of Birmingham, where nearly 250 participants from across four continents were brought together by their mutual interest in scientific discovery. There are many challenges still facing our community, both scientific and societal. By building on the successes of the past, recognising fantastic achievements in the present, and always looking to what we might accomplish in the future, the global MASC community will continue to flourish for years to come. [ABSTRACT FROM AUTHOR]

The oxime functional group is pivotal in chemistry, finding extensive applications in medical science, catalysis, organic functional group transformations, and the recognition of essential and toxic analytes. While the coordination chemistry of oxime derivatives has been thoroughly explored and several reviews have been published on this topic in reputable journals, a comprehensive review encompassing various aspects such as crystal engineering, cation and anion recognition, as well as coordination chemistry activities, is still in demand. This feature article highlights the diverse applications of oxime derivatives across multiple domains of chemistry, including medicine, agriculture, crystal engineering, coordination chemistry, and molecular recognition studies. Each of the oxime derivatives in this feature article are meticulously described in terms of their medicinal applications, crop protection, crystal engineering attributes, analyte recognition capabilities, and coordination chemistry aspects. By providing a comprehensive overview of their versatile applications, this article aims to inspire researchers to explore and develop novel oxime-based derivatives for future applications. [ABSTRACT FROM AUTHOR]

Attaining precise control over molecular arrangements is of paramount importance for numerous applications in nanotechnology, particularly in constructing molecular templates to accurately immobilize target materials on surfaces. A strategic combination of supramolecular and interfacial chemistry may serve to build a well‐organized molecular network, enabling the subsequent location of target molecules on specific positions of a surface. A supramolecular complex (compound 1) comprised of a melamine unit forming hydrogen bonds with dendritic arms terminated in a coumarin unit is utilized, which readily undergoes photodimerization. The research demonstrates the formation of well‐organized Langmuir films of compound 1 which can be transferred on substrates at low surface pressures adopting a lying‐flat orientation. Upon irradiation of the pristine films at 365 nm the coumarin units undergo photo‐cross linking, leading to the formation of a compact photo‐crosslinked film. Incubation of these photo‐crosslinked films in a solution containing 1‐hexanethiol results in the withdrawal of the melamine and the chemisorption of two thiol molecules per each melamine unit. The nanopores created by the removal of the melamine core are attributed to the disruption of hydrogen bonds in compound 1 by the thiols. This precisely defined molecular network holds significant promise as a template for orchestrating the arrangement of functional materials on surfaces. [ABSTRACT FROM AUTHOR]

Fluorine magnetic resonance imaging (19F-MRI) is particularly promising for biomedical applications owing to the absence of fluorine in most biological systems. However, its use has been limited by the lack of safe and water-soluble imaging agents with high fluorine contents and suitable relaxation properties. We report innovative 19F-MRI agents based on supramolecular dendrimers self-assembled by an amphiphilic dendrimer composed of a hydrophobic alkyl chain and a hydrophilic dendron. Specifically, this amphiphilic dendrimer bears multiple negatively charged terminals with high fluorine content, which effectively prevented intra- and intermolecular aggregation of fluorinated entities via electrostatic repulsion. This permitted high fluorine nuclei mobility alongside good water solubility with favorable relaxation properties for use in 19F-MRI. Importantly, the self-assembling 19F-MRI agent was able to encapsulate the near-infrared fluorescence (NIRF) agent DiR and the anticancer drug paclitaxel for multimodal 19F-MRI and NIRF imaging of and theranostics for pancreatic cancer, a deadly disease for which there remains no adequate early detection method or efficacious treatment. The 19F-MRI and multimodal 19F-MRI and NIRF imaging studies on human pancreatic cancer xenografts in mice confirmed the capability of both imaging modalities to specifically image the tumors and demonstrated the efficacy of the theranostic agent in cancer treatment, largely outperforming the clinical anticancer drug paclitaxel. Consequently, these dendrimer nanosystems constitute promising 19F-MRI agents for effective cancer management. This study offers a broad avenue to the construction of 19F-MRI agents and theranostics, exploiting self-assembling supramolecular dendrimer chemistry. [ABSTRACT FROM AUTHOR]

Developing synthetic molecular devices for controlling ion transmembrane transport is a promising research field in supramolecular chemistry. These artificial ion channels provide models to study ion channel diseases and have huge potential for therapeutic applications. Compared with self‐assembled ion channels constructed by intermolecular weak interactions between smaller molecules or cyclic compounds, metallacage‐based ion channels have well‐defined structures and can exist as single components in the phospholipid bilayer. A naphthalene diimide‐based artificial chloride ion channel is constructed through efficient subcomponent self‐assembly and its selective ion transport activity in large unilamellar vesicles and the planar lipid bilayer membrane by fluorescence and ion‐current measurements is investigated. Molecular dynamics simulations and density functional theory calculations show that the metallacage spans the entire phospholipid bilayer as an unimolecular ion transport channel. This channel transports chloride ions across the cell membrane, which disturbs the ion balance of cancer cells and inhibits the growth of cancer cells at low concentrations. [ABSTRACT FROM AUTHOR]

Non-covalent interactions involving element-hydrogen contacts are a central part in supramolecular chemistry and play essential roles in biomolecular structure. Reported here is a systematic computational analysis of such interactions within XHn---YHm dimers, where X and Y are C, Si, N, P, O, S, F and Cl, respectively. Two functionals are employed – the widely used BP86 and the M06-2X functional especially designed for describing noncovalent interactions. The interaction energies are found to be correlated with charge separation to a degree of 80%, suggesting that these noncovalent interactions can be reasonably explained/predicted by their electrostatic component. Energy decomposition analyses on the other hand suggest that correlation effects are the underlying root of the interaction. The rarely discussed intermolecular vibrations are also analyzed and noted to sometimes intercede in the typical observation windows for molecular spectroscopy. Moreover, in some cases notable effects of the non-covalent interactions are noted upon internal vibrations of the partners. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) have attracted extensive interest for the next‐generation batteries, which, however, are facing great challenges due to the poor reversibility of zinc (Zn) anodes and side reactions of water decomposition. Herein, we demonstrated a strategy that the solvation sheath of Zn ions could be facilely regulated by supramolecular coordination chemistry by adding small amounts of cyclodextrins (CDs) and, hence, inhibited the side reactions and side products, widened the electrochemical window, facilitated the homogenous deposition of Zn ions, refined the Zn grains, and enhanced the stability of Zn anodes. Importantly, we demonstrated that compared with α‐ and β‐CD, the γ‐CD showed the best regulation effect of the solvation sheath of Zn ions either at the same molar ratio or at the same mass concentration, which could be ascribed to their difference in supramolecular coordination chemistry and the strongest interaction of γ‐CD with Zn ions. As a result, with γ‐CD, the Zn//Zn symmetric cells showed ultrahigh stability with a cycling lifespan of over 2400 h at a current density of 1 mA/cm2. These results highlight the regulation of solvation sheath by supramolecular coordination chemistry for highly stable Zn anodes and pave a new way to realize high‐performance ZIBs. [ABSTRACT FROM AUTHOR]

Different from most of the conventional platforms with dissatisfactory theranostic capabilities, supramolecular nanotheranostic systems have unparalleled advantages via the artful combination of supramolecular chemistry and nanotechnology. Benefiting from the tunable stimuli-responsiveness and compatible hierarchical organization, host–guest interactions have developed into the most popular mainstay for constructing supramolecular nanoplatforms. Characterized by the strong and diverse complexation property, cucurbit[8]uril (CB[8]) shows great potential as important building blocks for supramolecular theranostic systems. In this review, we summarize the recent progress of CB[8]-based supramolecular theranostics regarding the design, manufacture and theranostic mechanism. Meanwhile, the current limitations and corresponding reasonable solutions as well as the potential future development are also discussed. [ABSTRACT FROM AUTHOR]

The successful synthesis of the pentazolate anion (cyclo-...) has been a great breakthrough in the field of energetic materials. However, the detection methods for these energetic materials based on the pentazolate anion are quite rare. Herein, two fluorescent probes for cyclo-... anion were designed. Sensor 1 (TPE2N) was synthesized with a tetraphenylethylene functionalized by two cationic groups which can generate strong electrostatic interactions with pentazolate anion and result in specific fluorescent changes. Sensor 2 was designed based on sensor 1 and supramolecular cucurbit[7]uril (CB[7]). The unique structural features of CB[7] provide sites for the interaction between the cations and ... anion in its cavity, which would generate a platform for the detection and enhance the recognition performance. Isothermal titration calorimetry (ITC) experiment and fluorescence titration experiment indicate the binding molar ratio between sensor 1 with CB[7] is 1:2. Both sensors display typical aggregation-induced emission (AIE) features and good water-solubility. The sensors demonstrate excellent sensitivity to pentazole hydrazine salt with high enhancement constant (sensor 1: 1.34 x 106; sensor 2: 3.78 x 106) and low limit of detection (LOD: sensor 1 ¼ 4.33 mM; sensor 2 ¼ 1.54 mM). The formation of an AIE-based supramolecular sensor effectively improves the sensitivity to ... anion. In addition, the probes also have good selectivity of ... anion salts. The research would shed some light on the design of novel fluorescent sensors to detect pentazolate-based molecules and provides an example of supramolecular chemistry combined with fluorescent probes. [ABSTRACT FROM AUTHOR]

Over the last 15 years, squaramide-based receptors have attracted the attention of supramolecular chemists working in the field of anion recognition. Herein, we highlight examples of squaramide-based receptors that are able to bind, sense, extract and transport anions. [ABSTRACT FROM AUTHOR]

Highlights: Recent advances and design strategies for molecular machines working as collectives in building smart responsive materials and micro/nanoscale operations are summarized in this review. The modulation of collective behaviors characteristics and properties is summarized in focus, including reversibility, amplification, anisotropy and reconfigurability of smart materials, as well as reconfigurability, orthogonality and logical control of swarming. Experiences and paradigms in the field of micro/nanorobotics in collective construction, control strategies, and model transformations are expected to provide guidance for molecular machines to build reconfigurable, multi-dimensional, and multi-modularity advanced collectives. Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work. During the last 60 years, designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research. Effective progress has been made, attributed to advances in various fields such as supramolecular chemistry, biology and nanotechnology, and informatics. However, individual molecular machines are only capable of producing nanometer work and generally have only a single functionality. In order to address these problems, collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm. In this review, we comprehensively discuss recent developments in the collective behaviors of molecular machines. In particular, collective behavior is divided into two paradigms. One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials. The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations. We discuss design strategies for both modes and focus on the modulation of features and properties. Subsequently, in order to address existing challenges, the idea of transferring experience gained in the field of micro/nano robotics is presented, offering prospects for future developments in the collective behavior of molecular machines. [ABSTRACT FROM AUTHOR]

Aim: To develop nanoemulsions (NEs) loading amphotericin B (AmB) and to evaluate the influence of different excipients on the stability and the supramolecular organization, retention and toxicity of AmB. Materials & methods: The NEs were developed from different oils, surfactants, external media and anionic lipids (disteaoryl phosphatidylglycerol [DSPG] and dioleoyl phosphatidylglycerol [DOPG]). Their impact on the size, pH, zeta potential, AmB encapsulation efficiency, AmB retention and hemolytic potential of the NEs was evaluated. Results & conclusion: The use of soybean oil (lipid matrix), Span 80 (surfactant), phosphate buffer (external phase) and DSPG or DOPG (hydrophobic ion pair) provided better NE stability, higher AmB retention within the NEs and a safer formulation profile in hemolysis tests. Disteaoryl phosphatidylglycerol and dioleoyl phosphatidylglycerol form a hydrophobic ion pair with amphotericin B in nanoemulsions, enhancing drug retention after dispersion and decreasing its toxicity. [ABSTRACT FROM AUTHOR]

1,4-Bis(diphenylhydroxymethyl)benzene (H), a host compound possessing wheel-and-axle geometry, was found to possess host ability for dioxane (DIO), morpholine (MOR) and piperidine (PIP), forming inclusion compounds with each one with 1:2 host:guest ratios. This observation prompted an investigation of the host behaviour in mixtures of these guest compounds but where pyridine (PYR) was also considered (PYR was reported earlier to also form a 1:2 complex with H). In mixtures, H demonstrated significant affinities for, more especially, MOR and PIP, while DIO and PYR were usually disfavoured guest species. Single crystal X-ray diffraction experiments revealed that MOR (a favoured guest species) interacted by means of three hydrogen bonds with both adjacent guest and host molecules, plausibly explaining the host preference for this guest species; each of DIO, PYR and PIP were involved in only one interaction of this type with H. Total energy calculations revealed that the host-guest molecular pairs involving preferred MOR and PIP possessed significantly lower energies than those with disfavoured DIO and PYR. Thermal analyses demonstrated that the complex containing the least favoured guest compound, H‧2(DIO), possessed the lowest thermal stability of the four complexes, but these experiments did not clearly explain the affinity of H for MOR. [ABSTRACT FROM AUTHOR]

We can describe current contingency of supramolecular chemistry as "post-halogen bonding", with clear reference to the success of the σ-hole model and the halogen bond concepts. This phase is characterized by a strong push towards a new nomenclature for non-covalent interactions, a group-by-group one focusing on the electrophile. As such nomenclature increasingly meets IUPAC endorsement, its proposers report resistances to such ideas, especially in the inorganic and coordination chemistry communities. The whole issue has been generating considerable debate in the last decade. Herein we fully embrace such discussion in the hope of involving a larger share of the relevant communities. Alternative descriptions are here reevaluated, novel views reconnected with older ones, and it is ultimately questioned whether the introduction of such a nomenclature and its subtending ideas would be beneficial. The themes of appreciation of general trends in chemistry, of counterintuitive interactions, of positioning of novel nomenclature with respect to existing ones, and of the extension of group-by-group naming from main block to d-block elements – as key and currently unresolved issues – are discussed. Equivalent, alternative and arguably more comprehensive descriptions are tentatively given, in the hope to overcome controversies together in the pursuit of higher rewards: a comprehensive shared view of supramolecular forces and a common language to express it. [ABSTRACT FROM AUTHOR]

Five-membered pyrroline nitroxides with high-potential is fascinating as catholyte for aqueous organic redox flow batteries (AORFBs), however, it suffers from a primary deficiency of insufficient stability due to ring-opening side reaction. Herein we report a spatial structure regulation strategy by host-guest chemistry, encapsulating 3-carbamoyl-2,2,5,5-tetramethylpyrroline-1-oxyl (CPL) into hydrosoluble cyclodextrins (CDs) with an inclusion structure of N-O· head towards cavity bottom, to boost the solubility and cyclability of pyrroline nitroxides significantly. The armor-clad CPL (CPL⊂HP-β-CD) catholyte in 0.05-0.5 M presents a battery capacity fade rate as low as 0.002 %/cycle (0.233 %/day) compared to the sole CPL in 0.05 M (0.039 %/cycle or 5.23 %/day) over 500 cycles in assembled AORFBs. The optimized reclining spatial structure with N-O· head towards CD cavity bottom effectively inhibits the attack of Lewis base species on the hydrogen abstraction site in pyrroline ring, and thus avoids the ring-opening side reaction of pyrroline nitroxides. [ABSTRACT FROM AUTHOR]

Introduction and aim: At present, several microbial diseases are prominent and of concern worldwide. The intent of this study was to examine the antibacterial potential of newly synthesized tetradentate macrocyclic complexes against different bacterial strains. The macrocyclic scaffold has gained attention as a biologically active class of supramolecular chemistry due to its unique properties and ability to target various microorganisms. Thus, the goal of the present study was to develop a series of biologically active transition metal-based macrocycles. Material and methods: All macrocyclic compounds were synthesized by a template method and validated by molar conductivity, elemental studies, and spectral and magnetic studies. Antibacterial activities of all metal complexes were evaluated against Escherichia coli (MTCC 739) and Staphylococcus aureus (MTCC 731) bacterial strains by taking ampicillin as a standard reference drug. DNA photocleavage potential was explored using agarose gel electrophoresis. Results: Results revealed the formation of novel macrocyclic complexes via tetra nitrogen bond trapping of metals. Copper complexes have strong potential against S. aureus bacteria as copper and nickel both show good DNA photocleavage potential. Concusion: The findings endorse the biomedical relevance of these macrocyclic scaffolds, suggesting avenues for further exploration in targeted drug delivery and potential clinical applications. The proposed octahedral geometry for the complexes enhances our understanding of their structural aspects. This research contributes substantively to the field, laying the foundation for future investigations in advanced antimicrobial design and application. [ABSTRACT FROM AUTHOR]

Crystallography Reviews is a journal that publishes reviews on various topics in crystallography and crystal growth. It covers theoretical and applied aspects of biological, chemical, industrial, mineralogical, and physical crystallography. The journal has been published since 1987 and has seen an increase in article downloads over the years. The current issue includes articles on inclusion compounds, cocrystallization, organic crystal formation, and calcium oxalate crystals in plants. Additionally, the journal provides book reviews and welcomes submissions for review articles and book suggestions. [Extracted from the article]