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The confinement effects within coordination cages present powerful tools in modern chemistry, particularly for the synthesis and manipulation of complex molecules. This concept article reviews the use of coordination cages to stabilize and tune the properties of polyoxometalates (POMs), a class of nano-sized metallic clusters, expanding the focus beyond traditional organic reactions. The article provides a brief overview of coordination cages, POM chemistry and discusses the encapsulation of POMs in coordination cages, highlighting how these cages provide a confinement effect that enhances the stability and reactivity of POMs. Additionally, the concept of cavity-directed synthesis is explored as a method for creating labile POMs, which are often unstable in aqueous conditions, underlining its implications for supramolecular catalysis. Future research will focus on expanding the structures and applications of encapsulated POMs, as well as improving cage designs to unlock new cluster architectures., (© 2024 Wiley-VCH GmbH.)

Supramolecular functional materials can be used to overcome some of the most challenging tasks in materials science, where the dynamic nature of supramolecular interactions can be leveraged to fine-tune the properties of the material for a given task. The Lindqvist hexavanadate family of polyoxometalates (POMs) have emerged as particularly interesting candidates to be used in supramolecular materials due to their redox and Lewis acid properties that enable their application in the fields of energy conversion/storage or catalysis. Despite their promising potential, hexavanadate clusters are underrepresented in the field of supramolecular materials, mainly due to the synthetic challenges related to their inherent reactivity. In this work, pillar[5]arene was successfully grafted onto a Lindqvist hexavanadate and the resulting structure was confirmed by single crystal X-ray diffraction (SC-XRD), presenting the first example of a crystal structure of a POMcovalently functionalized with a pillar[5]arene. By introducing a ditopic guest molecule that could interlink pillar[5]arene moieties, host-guest interactions were leveraged as the driving force for the formation of supramolecular assemblies incorporating hexavanadate clusters in a controlled manner. The enhanced catalytic performance of the resulting aggregates confirmed their potential application as functional catalytic materials. This novel approach for developing hexavanadate-based catalysts reported here showcases the potential of using host-guest interactions as a means to introduce catalytically active metal-oxo clusters into supramolecular frameworks., (© 2024 Wiley-VCH GmbH.)

The artificial microenvironments inside coordination cages have gained significant attention for performing enzyme-like catalytic reactions by facilitating the formation of labile and complex molecules through a "ship-in-a-bottle" approach. Despite many fascinating examples, this approach remains scarcely explored in the context of synthesizing metallic clusters such as polyoxometalates (POMs). The development of innovative approaches to control and influence the speciation of POMs in aqueous solutions would greatly advance their applicability and could ultimately lead to the formation of elusive clusters that cannot be synthesized by using traditional methods. In this study, we employ host-guest stabilization within a coordination cage to enable a novel cavity-directed synthesis of labile POMs in aqueous solutions under mild conditions. The elusive Lindqvist [M 6 O 19 ] 2- (M=Mo or W) POMs were successfully synthesized at room temperature via the condensation of molybdate or tungstate building blocks within the confined cavity of a robust and water-soluble Pt 6 L 4 (NO 3 ) 12 coordination cage. Importantly, the encapsulation of these POMs enhances their stability in water, rendering them efficient catalysts for environmentally friendly and selective sulfoxidation reactions using H 2 O 2 as a green oxidant in a pure aqueous medium. The approach developed in this paper offers a means to synthesize and stabilize the otherwise unstable metal-oxo clusters in water, which can broaden the scope of their applications., (© 2024 Wiley‐VCH GmbH.)

Although anti-rheumatoid arthritis (RA) 33 antibodies have been reported to be present in various connective tissue diseases (CTDs), the clinical significance of anti-RA33 in CTDs is still obscure. This study was performed to explore the clinical significance of anti-RA33 in CTDs, especially systemic lupus erythematosus (SLE). A total of 565 patients with positive anti-nuclear antibodies who had been tested for anti-RA33 were included in this study and were further classified into RA33-positive and RA33-negative groups. The association between anti-RA33 and the clinical features of CTDs was examined. Receiver operating characteristic (ROC) analysis was performed to explore the diagnostic value of anti-RA33 in SLE and SLE-related organ involvement. The results showed that SLE was the most common disease in CTD patients positive for anti-RA33 (48.8%). Compared with the RA33-negative group, higher proportions of SLE-associated antibodies and SLE patients with a high disease activity as well as lower levels of serum complement components were observed in the RA33-positive group (all p < 0.05). Furthermore, CTD patients with positive anti-RA33 were more likely to suffer from mucocutaneous and hematological involvement as well as interstitial lung disease (all p < 0.05). ROC analysis revealed an area under the curve value of 0.634 (95% confidence interval: 0.587-0.681) for anti-RA33 in the diagnosis of SLE, with a specificity and sensitivity of 92.9% and 13.5%, respectively. Taken together, this study reveals a significant association between anti-RA33 and the clinical features of CTDs, especially SLE, indicating a potential clinical significance of anti-RA33 in the management of SLE.

Objective: Anti-Ro60 and anti-Ro52 antibodies are associated with different connective tissue diseases (CTDs). However, the clinical significance of anti-Ro antibodies is not always consistent among different global regions. The aim of this study was to investigate the clinical characteristics of patients with anti-Ro antibodies., Methods: A total of 1596 inpatients with anti-Ro antibodies were included in the study. Demographic, clinical, and serological data were compared between individuals with different profiles of anti-Ro antibodies: patients with anti-Ro52 antibodies alone, patients with anti-Ro60 antibodies alone, and patients with combined anti-Ro52 and anti-Ro60 antibodies., Results: Of the 1596 patients, 1362 (85.3%) were female, the mean age was 45.5 years, and systemic lupus erythematosus (SLE) (46.0%) and Sjogren's syndrome (SS) (19.0%) were the most common CTD diagnoses. Among the patients with anti-Ro52 antibodies alone, idiopathic inflammatory myopathy (18.8%) and SLE (17.6%) were the most common CTD diagnoses. The coexistent autoantibodies of this group were significantly lower compared with those of the other two groups, while the presence of anti-Jo1 antibodies were significantly higher compared with those of the other two groups (3.7% vs. 0.6% vs. 1.9%, p = 0.029). In addition, the patients with isolated anti-Ro52 antibodies were more likely to suffer from interstitial lung disease (35.5% vs. 11.3% vs. 13.7%, p < 10 -4 ) and pulmonary arterial hypertension (10.1% vs. 5.3% vs. 3.6%, p = 0.001) compared with the other two groups of patients. Compared with patients with isolated anti-Ro52 or anti-Ro60 antibodies, the patients with combined anti-Ro52 and anti-Ro60 antibodies were more likely to suffer from xerophthalmia and xerostomia. Furthermore, hypocomplementemia, hyperglobulinemia, and proteinuria were particularly prevalent in patients with anti-Ro60 antibodies., Conclusion: Different profiles of anti-Ro antibodies were significantly associated with clinical phenotypic features in CTDs, indicating the potential diagnostic and prognostic value of these antibodies in clinical practice., Competing Interests: The authors have declared that they have no competing interests., (Copyright © 2023 Hai-Tao Yang et al.)

Diversification of the structures and the applications possible for foldamers rely on expansion of the building block library available for their synthesis. In this work, we describe the synthesis of a range of three dimensional heteroaromatic monomers, based on iptycene scaffolds, that are suitable for the synthesis of aromatic oligoamide foldamers. These units can be obtained in gram quantities in up to 80 % yield through [4+2] cycloaddition between diester, diamine, and amino acid derivatives of 1,8-diazaanthracenes and a variety of dienophiles. X-ray structural studies of the monomers and an oligomer show that the new motif orients the two heterocyclic rings and attached groups at an angle of approximately 120° to each other, opening new geometric considerations for the design of this class of foldamer., (© 2021 Wiley-VCH GmbH.)

Non-covalent interactions are important for directing protein folding across multiple intermediates and can even provide access to multiple stable structures with different properties and functions. Herein, we describe an approach for mimicking this behavior in the self-assembly of metal-organic cages. Two ligands, the bend angles of which are controlled by non-covalent interactions and one ligand lacking the above-mentioned interactions, were synthesized and used for self-assembly with Pd 2+ . As these weak interactions are easily broken, the bend angles have a controlled flexibility giving access to M 2 (L1) 4 , M 6 (L2) 12 , and M 12 (L2) 24 cages. By controlling the self-assembly conditions this process can be directed in a stepwise fashion. Additionally, the multiple endohedral hydrogen-bonding sites on the ligand were found to play a role in the binding and discrimination of neutral guests., (© 2020 Wiley-VCH GmbH.)

Luminescent supramolecular lanthanide edifices have many potential applications in biology, environments, and materials science. However, it is still a big challenge to improve the luminescent performance of multinuclear lanthanide assemblies in contrast to their mononuclear counterparts. Herein, we demonstrate that combination of intraligand charge transfer (ILCT) sensitization and coordination-driven self-assembly gives birth to bright Eu III tetrahedral cages with a record emission quantum yield of 23.1%. The ILCT sensitization mechanism has been unambiguously confirmed by both time-dependent density functional theory calculation and femtosecond transient absorption studies. Meanwhile, dual-responsive sensing toward both anions and cations has been demonstrated making use of the ILCT transition on the ligand. Without introduction of additional recognition units, high sensitivity and selectivity are revealed for the cage in both turn-off luminescent sensing toward I - and turn-on sensing toward Cu 2+ . This study offers important design principles for the future development of luminescent lanthanide molecular materials.

We report here the first example of concentration-triggered helicate-to-tetrahedron transformation in supramolecular lanthanide edifices, along with their highly efficient and selective luminescence sensing properties toward PA at the ppb level.

The purpose of this study was to explore variations in how contemporary couples from five different Asian regions negotiate disagreements. Video recordings of 50 couples (10 each from Japan, Korea, Mainland China, Taiwan, and Hong Kong) discussing unresolved disagreements provided raw data for quantitative and qualitative analyses. First, teams of coders from each region used a common protocol to make quantitative ratings of content themes and interaction patterns for couples from their own region. An interregional panel of investigators then performed in-depth qualitative reviews for half of these cases, noting cultural differences not only in observed patterns of couple behavior but also in their own perceptions of these patterns. Both quantitative and qualitative analyses revealed clear regional differences on dimensions such as overt negativity, demand-withdraw interaction, and collaboration. The qualitative results also provided a richer, more nuanced view of other (e.g., gender-linked) conflict management patterns that the quantitative analyses did not capture. Inconsistencies between qualitative and quantitative data and between the qualitative observations of investigators from different regions were most pronounced for couples from Korea and Japan, whose conflict styles were subtler and less direct than those of couples from the other regions., (© FPI, Inc.)