Catálogo de publicaciones - revistas

<jats:p>Catalytic asymmetric methods for the synthesis of synthetically versatile P‐stereogenic building blocks offer an efficient and practical approach for the diversity‐oriented preparation of P‐chiral phosphorus compounds. Herein, we report the first nickel‐catalyzed synthesis of P‐stereogenic secondary aminophosphine‐boranes by the asymmetric addition of primary phosphines to azo compounds. We further demonstrate that the P−H and P−N bonds on these phosphanyl hydrazine building blocks can be reacted sequentially and stereospecifically to access various P‐stereogenic compounds with structural diversity.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The elevated glutathione (GSH) level in solid tumors has been used as a major hallmark for GSH‐responsive nanoparticles to enhance targeting efficiency and specificity. Meanwhile, GSH is mainly synthesized inside the hepatocytes of the liver in the body and constantly released into the blood through hepatic GSH efflux to regulate redox potential of the entire body. However, it remains largely unknown how this hepatic GSH efflux affects the tumor targeting of GSH‐responsive nanoparticles. Herein, we report that depletion of hepatic GSH enhanced the tumor targeting of GSH‐responsive indocyanine green‐conjugated Au<jats:sub>25</jats:sub> nanoclusters coated with 18 GSH ligand (ICG‐Au<jats:sub>25</jats:sub>SG<jats:sub>18</jats:sub>). The dissociation of ICG from Au<jats:sub>25</jats:sub>SG<jats:sub>18</jats:sub> by the hepatic GSH through thiol‐exchange reaction and the subsequent hepatobiliary clearance of the detached ICG were slowed down by GSH depletion, which in turn prolonged the blood circulation of intact ICG‐Au<jats:sub>25</jats:sub>SG<jats:sub>18</jats:sub> and enhanced its tumor targeting. Our work highlights glutathione‐mediated crosstalk between the liver and tumor, in addition to well‐known Kupffer cell‐mediated uptake, in the tumor targeting of engineered nanoparticles, which could be modulated to enhance targeting efficiency and specificity of cancer nanomedicines while reducing their nonspecific accumulation.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The key issue in the 5‐hydroxymethylfurfural oxidation reaction (HMFOR) is to understand the synergistic mechanism involving the protons deintercalation of catalyst and the adsorption of the substrate. In this study, a Pd/NiCo catalyst was fabricated by modifying Pd clusters onto a Co‐doped Ni(OH)<jats:sub>2</jats:sub> support, in which the introduction of Co induced lattice distortion and optimized the energy band structure of Ni sites, while the Pd clusters with an average size of 1.96 nm exhibited electronic interactions with NiCo support, resulting in electron transfer from Pd to Ni sites. The resulting Pd/NiCo exhibited low onset potential of 1.32 V and achieved a current density of 50 mA/cm<jats:sup>2</jats:sup> at only 1.38 V. Compared to unmodified Ni(OH)<jats:sub>2</jats:sub>, the Pd/NiCo achieved an 8.3‐fold increase in peak current density. DFT calculations and in situ XAFS revealed that the Co sites affected the conformation and band structure of neighboring Ni sites through CoO<jats:sub>6</jats:sub> octahedral distortion, reducing the proton deintercalation potential of Pd/NiCo and promoting the production of Ni<jats:sup>3+</jats:sup>−O active species accordingly. The involvement of Pd decreased the electronic transfer impedance, and thereby accelerated Ni<jats:sup>3+</jats:sup>−O formation. Moreover, the Pd clusters enhanced the adsorption of HMF through orbital hybridization, kinetically promoting the contact and reaction of HMF with Ni<jats:sup>3+</jats:sup>−O.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Single‐atom catalysts (SACs) have emerged as crucial players in catalysis research, prompting extensive investigation and application. The precise control of metal atom nucleation and growth has garnered significant attention. In this study, we present a straightforward approach for preparing SACs utilizing a photocatalytic radical control strategy. Notably, we demonstrate for the first time that radicals generated during the photochemical process effectively hinder the aggregation of individual atoms. By leveraging the cooperative anchoring of nitrogen atoms and crystal lattice oxygen on the support, we successfully stabilize the single atom. Our Pd<jats:sub>1</jats:sub>/TiO<jats:sub>2</jats:sub> catalysts exhibit remarkable catalytic activity and stability in the Suzuki–Miyaura cross‐coupling reaction, which was 43 times higher than Pd/C. Furthermore, we successfully depose Pd atoms onto various substrates, including TiO<jats:sub>2</jats:sub>, CeO<jats:sub>2</jats:sub>, and WO<jats:sub>3</jats:sub>. The photocatalytic radical control strategy can be extended to other single‐atom catalysts, such as Ir, Pt, Rh, and Ru, underscoring its broad applicability.</jats:p>

<jats:p>Ribosomally synthesized and post‐translationally modified peptides (RiPPs) are a fascinating group of natural products that exhibit diverse structural features and bioactivities. P450‐catalyzed RiPPs stand out as a unique but underexplored family. Here, we introduce a rule‐based genome mining strategy that harnesses the intrinsic biosynthetic principles of RiPPs, including the co‐occurrence, co‐conservation, and interactions between precursors and P450s, successfully facilitating the identification of diverse P450 catalyzed RiPPs. Intensive BGC characterization revealed four new P450s, KstB, ScnB, MciB, and SgrB, that can respectively catalyze Trp‐Trp‐Tyr (one C‐C and two C‐N bonds), Tyr‐Trp (C‐C bond), Trp‐Trp (C‐N bond), and His‐His (ether bond) crosslinks within three or four residues. KstB, ScnB, and MciB could accept non‐native precursors, suggesting they could be promising starting templates for bioengineering to construct macrocycles. Our study highlights the potential of P450s in expanding the chemical diversity of strained macrocyclic peptides and enriching biocatalytic tools for peptide macrocyclization.</jats:p>

<jats:p>Resurfacing perovskite nanocrystals (NCs) with tight‐binding and conductive ligands to resolve the dynamic ligands – surface interaction is the fundamental issue for their applications in perovskite light‐emitting diodes (PeLEDs). Although various types of surface ligands have been proposed, these ligands either exhibit weak Lewis acid/based interactions or need high polar solvents for dissolution and passivation, resulting in a compromise in the efficiency and stability of PeLEDs. Herein, we report a chemically reactive agent (Iodotrimethylsilane, TMIS) to address the trade‐off among conductivity, solubility and passivation using all‐inorganic CsPbI3 NCs. The liquid TMIS ensures good solubility in non‐polar solvents and reacts with oleate ligands and produces in‐situ HI for surface etching and passivation, enabling strong‐binding ligands on the NCs surface. We report, as a result, red PeLEDs with an external quantum efficiency (EQE) of ~23%, which is 11.2‐fold higher than the control, and is among the highest CsPbI3 PeLEDs. We further demonstrate the university of this ligand strategy in the pure bromide system (CsPbBr3), and report EQE of ~20% at 640, 652, and 664 nm. This represents the first demonstration of ligand strategy that applies to different systems and works effectively in red PeLEDs spanning emission from pure‐red to deep‐red.</jats:p>

<jats:p>Spin frustration, resulted from geometric frustration and a systematical inability to satisfy all antiferromagnetic (AF) interactions between the unpaired spins simultaneously, is under spotlight for its importance in physics and materials science. Spin frustration is treated as structural basis of quantum spin liquid (QSL). Featuring flexible chemical structures, organic radical species exhibit great potential in building spin‐frustrated molecules and lattices. Until now, the reported examples of spin‐frustrated organic radical compounds include triradicals, tetrathiafulvalene (TTF) radicals and derivatives, [Pd(dmit)2] compounds (dmit = 1,3‐dithiol‐2‐thione‐4,5‐dithiolate), nitronyl nitroxides, fullerenes, polycyclic aromatic hydrocarbons (PAHs), and other heterocyclic compounds, where the spin frustration is generated intra‐ or intermolecularly. In this Minireview, we provide a brief summary for the reported radical compounds possess spin frustration. The related data, including magnetic exchange coupling parameters, spin models, frustration parameters, and crystal lattices, are summarized and discussed.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The catalytic C(sp<jats:sup>3</jats:sup>)−C(sp<jats:sup>3</jats:sup>) coupling of alkyl halides and tertiary amines offers a promising tool for the rapid decoration of amine skeletons. However, this approach has not been well established, partially due to the challenges in precisely distinguishing and controlling the reactivity of amine‐coupling partners and their product homologues. Herein, we developed a metal‐free photocatalytic system for the aminomethylation of alkyl halides through radical‐involved C(sp<jats:sup>3</jats:sup>)−C(sp<jats:sup>3</jats:sup>) bond formation, allowing for the synthesis of sterically congested tertiary amines that are of interest in organic synthesis but not easily prepared by other methods. Mechanistic studies disclosed that sterically hindered <jats:italic>N</jats:italic>‐substituents are key to activate the amine coupling partners by tuning their redox potentials to drive the reaction forward.</jats:p>

<jats:p>High‐resolution crystal structures of lysozyme in the presence of the potential drug VIVO(acetylacetonato)2 under two different experimental conditions have been solved. The crystallographic study reveals the loss of the ligands, the oxidation of VIV to VV and the subsequent formation of adducts of the protein with two different polyoxidovanadates: [V4O12]4–, which interacts with lysozyme non‐covalently, and the unprecedented [V20O54(NO3)]n–, which is covalenty bound to the side chain of an aspartate residue of symmetry related molecules.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The synthesis of single‐molecule magnets (SMMs), magnetic complexes capable of retaining magnetization blocking for a long time at elevated temperatures, has been a major concern for magnetochemists over the last three decades. In this review, we describe basic SMMs and the different approaches that allow high magnetization‐blocking temperatures to be reached. We focus on the basic factors affecting magnetization blocking, magnetic axiality and the height of the blocking barrier, which can be used to group different families of complexes in terms of their SMM efficiency. Finally, we discuss several practical routes for the design of mono‐ and polynuclear complexes that could be applied in memory devices.</jats:p>