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Clip‐off Chemistry is a synthetic strategy that our group previously developed to obtain new molecules and materials through selective cleavage of bonds. Herein, we report recent work to expand Clip‐off Chemistry by introducing into it a retrosynthetic analysis step that, based on virtual extension of the products through cleavable bonds, enables one to define the required precursor materials. As proof‐of‐concept, we have validated our new approach by synthesising and characterising four aldehyde‐functionalised Rh(II)‐based complexes: a homoleptic cluster; a cis‐disubstituted paddlewheel cluster; a macrocycle; and a crown. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) based on high-connected nets are generally very attractive due to their combined robustness and porosity. Here, we describe the synthesis of BCN-348, a new high-connected Zr-MOF built from an 8-connected (8-c) cubic Zr-oxocluster and an 8-c organic linker. BCN-348 contains a minimal edge-transitive 3,4,8-c eps net, and combines mesoporosity with thermal and hydrolytic stability. Encouraging results from preliminary studies on its use as a catalyst for hydrolysis of a nerve-agent simulant suggest its potential as an agent for detoxification of chemical weapons and other pernicious compounds. [ABSTRACT FROM AUTHOR]

Increasing the chemical complexity of metal–organic cages (MOCs) or polyhedra (MOPs) demands control over the simultaneous organization of diverse organic linkers and metal ions into discrete caged structures. Herein, we show that a pre-assembled complex of the archetypical cuboctahedral MOP can be used as a template to replicate such caged structure, one having a "triblock Janus-type" configuration that is both heterometallic and heteroleptic. [ABSTRACT FROM AUTHOR]

We have synthesised and characterised the two possible isomers of heteroleptic trigonal antiprismatic M12L6L′6 MOPs by screening reactions of rhodium acetate with different pairs of complementary dicarboxylate linkers. The resulting 12 new MOPs (eight of isomer A + four of isomer B) are microporous in the solid state, exhibiting Brunauer–Emmett–Teller (BET) surface areas as high as 770 m2 g−1. [ABSTRACT FROM AUTHOR]

Bond breaking is an essential process in chemical transformations and the ability of researchers to strategically dictate which bonds in a given system will be broken translates to greater synthetic control. Here, we report extending the concept of selective bond breaking to reticular materials in a new synthetic approach that we call Clip‐off Chemistry. We show that bond‐breaking in these structures can be controlled at the molecular level; is periodic, quantitative, and selective; is effective in reactions performed in either solid or liquid phases; and can occur in a single‐crystal‐to‐single‐crystal fashion involving the entire bulk precursor sample. We validate Clip‐off Chemistry by synthesizing two topologically distinct 3D metal‐organic frameworks (MOFs) from two reported 3D MOFs, and a metal‐organic macrocycle from metal‐organic polyhedra (MOP). Clip‐off Chemistry opens the door to the programmed disassembly of reticular materials and thus to the design and synthesis of new molecules and materials. [ABSTRACT FROM AUTHOR]

The plant‐specific class XI myosins (MyoXIs) play key roles at the molecular, cellular and tissue levels, engaging diverse adaptor proteins to transport cargoes along actin filaments. To recognize their cargoes, MyoXIs have a C‐terminal globular tail domain (GTD) that is evolutionarily related to those of class V myosins (MyoVs) from animals and fungi. Despite recent advances in understanding the functional roles played by MyoXI in plants, the structure of its GTD, and therefore the molecular determinants for cargo selectivity and recognition, remain elusive. In this study, the first crystal structure of a MyoXI GTD, that of MyoXI‐K from Arabidopsis thaliana, was elucidated at 2.35 Å resolution using a low‐identity and fragment‐based phasing approach in ARCIMBOLDO_SHREDDER. The results reveal that both the composition and the length of the α5–α6 loop are distinctive features of MyoXI‐K, providing evidence for a structural stabilizing role for this loop, which is otherwise carried out by a molecular zipper in MyoV GTDs. The crystal structure also shows that most of the characterized cargo‐binding sites in MyoVs are not conserved in plant MyoXIs, pointing to plant‐specific cargo‐recognition mechanisms. Notably, the main elements involved in the self‐regulation mechanism of MyoVs are conserved in plant MyoXIs, indicating this to be an ancient ancestral trait. [ABSTRACT FROM AUTHOR]

Use of preformed metal‐organic polyhedra (MOPs) as supermolecular building blocks (SBBs) for the synthesis of metal‐organic frameworks (MOFs) remains underexplored due to lack of robust functionalized MOPs. Herein we report the use of polycarboxylate cuboctahedral RhII‐MOPs for constructing highly‐connected MOFs. Cuboctahedral MOPs were functionalized with carboxylic acid groups on their 12 vertices or 24 edges through coordinative or covalent post‐synthetic routes, respectively. We then used each isolated polycarboxylate RhII‐MOP as 12‐c cuboctahedral or 24‐c rhombicuboctahedral SBBs that, upon linkage with metallic secondary building units (SBUs), afford bimetallic highly‐connected MOFs. The assembly of a pre‐synthesized 12‐c SBB with a 4‐c paddle‐wheel SBU, and a 24‐c SBB with a 3‐c triangular CuII SBU gave rise to bimetallic MOFs having ftw (4,12)‐c or rht (3,24)‐c topologies, respectively. [ABSTRACT FROM AUTHOR]

The addition of compounds to scavenge the radical species produced during biological small‐angle X‐ray scattering (BioSAXS) experiments is a common strategy to reduce the effects of radiation damage and produce better quality data. As almost half of the experiments leading to structures deposited in the SASBDB database used scavengers, finding potent scavengers would be advantageous for many experiments. Here, four compounds, three nucleosides and one nitrogenous base, are presented which can act as very effective radical‐scavenging additives and increase the critical dose by up to 20 times without altering the stability or reducing the contrast of the tested protein solutions. The efficacy of these scavengers is higher than those commonly used in the field to date, as verified for lysozyme solutions at various concentrations from 7.0 to 0.5 mg ml−1. The compounds are also very efficient at mitigating radiation damage to four proteins with molecular weights ranging from 7 to 240 kDa and pH values from 3 to 8, with the extreme case being catalase at 6.7 mg ml−1, with a scavenging factor exceeding 100. These scavengers can therefore be instrumental in expanding BioSAXS to low‐molecular‐weight and low‐concentration protein samples that were previously inaccessible owing to poor data quality. It is also demonstrated that an increase in the critical dose in standard BioSAXS experiments leads to an increment in the retrieved information, in particular at higher angles, and thus to higher resolution of the model. [ABSTRACT FROM AUTHOR]

This document, published in the journal Angewandte Chemie, discusses various research articles in the field of chemistry. One article explores the use of bond scission as a synthetic tool to design new molecules and materials, showcasing the synthesis of Rh(II)-based architectures through the disassembly of metal-organic polyhedra. Another article focuses on the incorporation of Pd nanoparticles into MOFs for high selectivity in CO esterification. Additionally, there is a report on the use of sulfonium salt reagents for introducing deuterated alkyl groups in drug discovery, and a study on adaptive catalysts that can switch selectivity in hydrogenation reactions. Lastly, the document mentions a research article on the photophysics of [Ru(bpy)3]2+, highlighting the importance of rate-determining states in understanding its behavior. [Extracted from the article]

This article discusses various research articles published in the journal Angewandte Chemie International Edition. One research article by Jorge Albalad, Inhar Imaz, Daniel Maspoch, et al. explores the use of bond scission as a synthetic tool to design new molecules and materials. They demonstrate this concept by obtaining unprecedented Rh(II)-based architectures through the disassembly of metal-organic polyhedra. Another research article by Weijie Yang, Hai-Long Jiang, et al. focuses on incorporating Pd nanoparticles into MOFs for high selectivity in CO esterification. Yoshinari Sawama, et al. report on sulfonium salt reagents for introducing deuterated alkyl groups in drug discovery, while Alexis Bordet, Walter Leitner, et al. discuss the adaptivity of a catalyst in the hydrogenation of heteroaromatics. Lastly, Leticia González, et al. investigate the photophysics of [Ru(bpy)3]2+ and propose a kinetic model for its behavior. [Extracted from the article]

Abstract: Supramolecular nanocapsule 1⋅(BArF)8 is able to sequentially and selectively entrap recently discovered U2@C80 and unprecedented Sc2CU@C80, simply by soaking crystals of 1⋅(BArF)8 in a toluene solution of arc‐produced soot. These species, selectively and stepwise absorbed by 1⋅(BArF)8, are easily released, obtaining highly pure fractions of U2@C80 and Sc2CU@C80 in one step. Sc2CU@C80 represents the first example of a mixed metal actinide‐based endohedral metallofullerene (EMF). Remarkably, the host–guest studies revealed that 1⋅(BArF)8 is able to discriminate EMFs with the same carbon cage but with different encapsulated cluster and computational studies provide support for these observations. [ABSTRACT FROM AUTHOR]

This chemistry is first used to synthesize two 3D metal-organic frameworks (MOFs) and a metal-organic macrocycle from precursor reticular materials. This chemistry is first used to synthesize two 3D metal-organic frameworks (MOFs) and a metal-organic macrocycle from precursor reticular materials. Cover Picture: Clip-off Chemistry: Synthesis by Programmed Disassembly of Reticular Materials (Angew. [Extracted from the article]

Short-peptide supramolecular (SPS) hydrogels are a class of materials that have been found to be useful for (bio)technological applications thanks to their biocompatible nature. Among the advantages reported for these peptides, their economic affordability and easy functionalization or modulation have turned them into excellent candidates for the development of functional biomaterials. We have recently demonstrated that SPS hydrogels can be used to produce high-quality protein crystals, improve their properties, or incorporate relevant materials within the crystals. In this work, we prove that hydrogels based on methionine and tyrosine are also good candidates for growing high-quality crystals of the three model proteins: lysozyme, glucose isomerase, and thaumatin. [ABSTRACT FROM AUTHOR]

Catalases are among the main scavengers of reactive oxygen species (ROS) present in the peroxisome, thereby preventing oxidative cellular and tissular damage. In human, multiple diseases are associated with malfunction of these organelles, which causes accumulation of ROS species and consequently the inefficient detoxification of cells. Despite intense research, much remains to be clarified about the precise molecular role of catalase in cellular homeostasis. Yeast peroxisomes and their peroxisomal catalases have been used as eukaryotic models for oxidative metabolism, ROS generation and detoxification, and associated pathologies. In order to provide reliable models for oxidative metabolism research, we have determined the high-resolution crystal structures of peroxisomal catalase from two important biotechnology and basic biology yeast models, Pichia pastoris and Kluyveromyces lactis. We have performed an extensive functional, biochemical and stability characterization of both enzymes in order to establish their differential activity profiles. Furthermore, we have analyzed the role of the peroxisomal catalase under study in the survival of yeast to oxidative burst challenges combining methanol, water peroxide, and sodium chloride. Interestingly, whereas catalase activity was induced 200-fold upon challenging the methylotrophic P. pastoris cells with methanol, the increase in catalase activity in the non-methylotrophic K. lactis was only moderate. The inhibitory effect of sodium azide and β-mercaptoethanol over both catalases was analyzed, establishing IC50 values for both compounds that are consistent with an elevated resistance of both enzymes toward these inhibitors. Structural comparison of these two novel catalase structures allows us to rationalize the differential susceptibility to inhibitors and oxidative bursts. The inherent worth and validity of the P. pastoris and K. lactis yeast models for oxidative damage will be strengthened by the availability of reliable structural-functional information on these enzymes, which are central to our understanding of peroxisomal response toward oxidative stress. Image 1 • Crystal structures of the peroxisomal catalases from Pichia pastoris at 2.3 Å and Kluyveromyces lactis at 1.85 Å. • Potassium and sodium ions provide structural stabilization to catalases. • NADPH is tightly bound to the catalase surface and prevents its inactivation. • Yeast catalases are remarkably tolerant to azide and 2-mercaptoethanol. • Exposure to H 2 O 2 with cations is more powerful than H 2 O 2 alone to inhibit yeast growth. [ABSTRACT FROM AUTHOR]

Herein, we present a novel methodology for synthesizing metal clusters or secondary building units (SBUs) that are subsequently employed to construct innovative metal-organic frameworks (MOFs) via dynamic covalent chemistry. Our approach entails extraction of SBUs from preformed MOFs through complete disassembly by clip-off chemistry. The initial MOF precursor is designed to incorporate the desired SBU, connected exclusively by cleavable linkers (in this study, with olefinic bonds). Cleavage of all the organic linkers (in this study, via ozonolysis under reductive conditions) liberates the SBUs functionalized with aldehyde groups. Once synthesized, these SBUs can be further reacted with amines in dynamic covalent chemistry to build new, rationally designed MOFs.

We have synthesised and characterised the two possible isomers of heteroleptic trigonal antiprismatic M 12 L 6 L' 6 MOPs by screening reactions of rhodium acetate with different pairs of complementary dicarboxylate linkers. The resulting 12 new MOPs (eight of isomer A + four of isomer B) are microporous in the solid state, exhibiting Brunauer-Emmett-Teller (BET) surface areas as high as 770 m 2 g -1 .

Herein we propose a new approach for deducing the topology of metal-organic frameworks (MOFs) assembled from organic ligands of low symmetry, which we call net-clipping . It is based on the construction of nets by rational deconstruction of edge-transitive nets comprising higher-connected molecular building blocks (MBBs). We have applied net-clipping to predict the topologies of MOFs containing zigzag ligands. To this end, we derived 2-connected (2-c) zigzag ligands from 4-c square-like MBBs by first splitting the 4-c nodes into two 3-c nodes and then clipping their two diagonally connecting groups. We demonstrate that, when this approach is applied to the 17 edge-transitive nets containing square-like 4-c MBBs, net-clipping leads to generation of 10 nets with different underlying topologies. Moreover, we report that literature and experimental research corroborate successful implementation of our approach. As proof-of-concept, we employed net-clipping to form three new MOFs built with zigzag ligands, each of which exhibits the deduced topology.

MXCuBE2 is the second-generation evolution of the MXCuBE beamline control software, initially developed and used at ESRF - the European Synchrotron. MXCuBE2 extends, in an intuitive graphical user interface (GUI), the functionalities and data collection methods available to users while keeping all previously available features and allowing for the straightforward incorporation of ongoing and future developments. MXCuBE2 introduces an extended abstraction layer that allows easy interfacing of any kind of macromolecular crystallography (MX) hardware component, whether this is a diffractometer, sample changer, detector or optical element. MXCuBE2 also works in strong synergy with the ISPyB Laboratory Information Management System, accessing the list of samples available for a particular experimental session and associating, either from instructions contained in ISPyB or from user input via the MXCuBE2 GUI, different data collection types to them. The development of MXCuBE2 forms the core of a fruitful collaboration which brings together several European synchrotrons and a software development factory and, as such, defines a new paradigm for the development of beamline control platforms for the European MX user community., (open access.)

Supramolecular nanocapsule 1⋅(BArF) 8 is able to sequentially and selectively entrap recently discovered U 2 @C 80 and unprecedented Sc 2 CU@C 80 , simply by soaking crystals of 1⋅(BArF) 8 in a toluene solution of arc-produced soot. These species, selectively and stepwise absorbed by 1⋅(BArF) 8 , are easily released, obtaining highly pure fractions of U 2 @C 80 and Sc 2 CU@C 80 in one step. Sc 2 CU@C 80 represents the first example of a mixed metal actinide-based endohedral metallofullerene (EMF). Remarkably, the host-guest studies revealed that 1⋅(BArF) 8 is able to discriminate EMFs with the same carbon cage but with different encapsulated cluster and computational studies provide support for these observations., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)