Comprehensive Summary:The ternary strategy has demonstrated its efficacy in improving charge transport in organic solar cells (OSCs). Here, three novel non-fullerene acceptors, SN6C9-4F, SN6C9-4Cl and SN6C10-4F, based on S, N-heteroacene linear backbone were designed and synthesized. The three acceptors exhibit excellent molecular coplanarity, high crystallinity and possess a deep-lying lowest unoccupied molecular orbital energy level, which is beneficial for charge transport and injection in organic field-effect transistors (OFETs). Notably, the OFET devices based on all three acceptors achieved impressive electron mobilities, with SN6C10-4F achieving up to 0.73 cm ²·V ^–1·s ^–1, which is one of the highest values among A-D-A type small molecules. In addition, the OSCs device based on PBDB-T:SN6C9-4F exhibited the best power conversion efficiency of 12.07% owing to its optimal morphology and enhanced charge transport. Moreover, the incorporation of SN6C9-4F into the efficient PM6:L8-BO binary system to form ternary OSCs resulted in extended absorption range, enhanced donor crystallization, improved and more balanced charge transport, ultimately leading to an improvement of PCE from 17.78% to 18.32%. This study highlights the potential of developing acceptors with distinct structures from Y-series acceptors to broaden absorption and regulate donor crystallization, providing a novel approach to enhance the PCE of OSCs.

Comprehensive Summary:Four polycyclic ten-membered lactones possessing unprecedented 10/6/5 tricyclic ring skeleton, named eutypetides A–D ( 1– 4), and an intriguing polyketide containing a hexahydroisobenzofuran-1(3 H)-one motif, named eutypetide E ( 5) were isolated from the marine-derived fungus Eutypella sp. F0219, together with three new related biosynthetic polyketides eutypetides F–H ( 6– 8). The absolute configurations of 1– 5 were unequivocally determined by single-crystal X-ray diffraction analyses (Cu Kα), modified Mosher’s method and electronic circular dichroism (ECD) calculations. Eutypetides G ( 7) showed remarkable anti-inflammatory activity and could reduce the mRNA expression of proinflammatory cytokines IL-1β, IL-6, TNF-α, and iNOS induced by LPS. Most notably, compounds 1– 4 were formed biogenetically from 6– 7 via the key intramolecular [4+2] cycloaddition, while compound 5 could be constructed biogenetically from 8 through the intramolecular [4+2] cycloaddition. All the above eight polyketides are proposed to originate from a C ₁₀ and a C ₆ fatty acid.

Comprehensive Summary: Acinetobacter baumannii infections pose a great threat to public health owing to upsurging antibiotic resistance. Capsular polysaccharides (CPS) are major virulence determinants of pathogenic bacteria and have attracted much attention as potential targets for vaccine development. However, the obtainability of structurally well-defined CPS-related oligosaccharides remains challenging. Herein, we report an efficient chemoenzymatic strategy for the first total synthesis of common CPS pentasaccharide repeating unit of Acinetobacter baumannii K27 and K44, containing a difficult-to-construct α-linked 5, 7-di- N-acetyllegionaminic acid (Leg5, 7Ac ₂) residue. The chemical synthesis of a branched tetrasaccharide precursor was accomplished by flexible orthogonal protecting-group manipulations and stereocontrolled glycosylations. Furthermore, the enzyme-catalyzed stereoselective installment of legionaminic acid residue into the tetrasaccharide, using one-pot multienzyme (OPME) synthesis system to produce sugar nucleotide CMP-Leg5, 7diN ₃ and subsequent α2, 6-sialyltransferase-catalyzed glycosylation, was achieved to synthesize the pentasaccharide.

Comprehensive Summary:The reaction between tripodal trisamidophosphine ligand H ₃PN ₃ ^Ar and V(Mes) ₃(THF) (Mes = mesityl) yields the vanadium(III) complex (PN ₃ ^Ar)V ( 1) with an open site in the axial position, which could coordinate with THF, pyridine, and NH ₃ to form the corresponding adducts ( 2– 4). The vanadium(III) center is redox-active, as demonstrated by cyclic voltammetry methods and chemical oxidation or reduction. Notably, a novel dinitrogen divanadium complex with a bridging N ₂ ligand, {K(THF)} ₂{[PN ₃ ^Ar]V} ₂( µ-N ₂) ( 6), was synthesized via treatment of 1 with 1 equivalent of potassium naphthalenide in THF under a N ₂ atmosphere. The electronic structures and binding properties of 6 are evaluated and discussed based on its DFT calculations. Additionally, these vanadium complexes ( 1, 5, 6) can serve as catalysts for the conversion of N ₂ into N(SiMe ₃) ₃ in the presence of reductants and Me ₃SiCl.

Comprehensive Summary:We report the design and development of a β-glucuronidase (β-Glu)-responsive ManNAz derivative, Glu-AAM, for tumor-selective metabolic glycoengineering. Glu-AAM enables specific labeling of tumor cell surface sialoglycans in the presence of overexpressed β-Glu in cancer cells, including breast, leukemia, and colorectal cancer cells. We demonstrate the high selectivity and efficiency of Glu-AAM-mediated metabolic glycoengineering across multiple cancer cell lines. Furthermore, we synthesized multivalent antibody-recruiting molecules (DBCO-Rha) that can be covalently attached to the azido-modified tumor cell surface, leading to potent antibody-dependent cellular phagocytosis and complement-dependent cytotoxicity. The octameric DBCO-Rha8 construct exhibited the most effective immune response. This integrated strategy of β-Glu-responsive metabolic glycoengineering and antibody-recruiting immunotherapy provides a promising platform for targeted cancer therapies and expands the toolbox of metabolic glycoengineering for cancer immunotherapy.

Comprehensive Summary:Post-polymerization modification provides an important approach to tuning the material properties of obtained polymers. In this work, we demonstrated a rational design of novel vinylcyclopropane monomer bearing a pendant N-hydroxylphthalimide redox ester, and explored its radical ring-opening polymerization behavior under visible-light conditions. Photochemical decarboxylation of resulted polymer provided unique access to poly(vinylcyclopropane) bearing single ester group in each repeating unit. This decarboxylative modification has greatly reshaped the thermal and mechanical properties, converting a glassy polymer into a soft, ductile, and rubber-like material.

Comprehensive Summary: Rapid dynamics and remarkable proton conduction induced by c onfined water in nanospaces have attracted much attentions from researchers, which is crucial for advancing the development of innovative proton conductors and deepening comprehension of proton and water transport mechanisms within biological systems. In this aspect, carbon nanotubes (CNTs) are frequently employed as a research platform. However, they possess certain limitations, such as their inherent electronic conductivity and extreme hydrophobicity, which can impede the accurate assessment and precise regulation of proton conduction. We herein prepared two 2D COFs with different hydrophilic fragment, and obtained maximum acid-free proton conductivity of 3.04 × 10 ^–4 S·cm ^–1 at 70 °C and 100% RH with Grotthuss type activation energy of 0.14 eV. This is mainly due to that the water molecules in the center of channel form strong hydrogen bonds, enhancing proton dissociation and guiding fast directional diffusion.

Comprehensive Summary:Ketenimine zwitterionic salt (KZS), a novel and stable ketenimine precursor, is still underexplored in the realm of chemical synthesis. In this study, we demonstrate the transformation of pyrrole derivatives through the cyclization of KZS with α-aminoketones. The diastereoselectivity of this reaction is influenced by the solvent, enabling the isolation of 3-hydroxypyrrolidine diastereomers with the highest reported dr value of 21 : 1. Furthermore, the chemoselectivity is modulated by the choice of base, yielding 2-aminopyrrole derivatives as the major products. This research offers a sustainable approach to harnessing the potential of KZS in organic synthesis, contributing to a greener chemical process.

Comprehensive Summary:The present work prepared a copper N-heterocyclic carbene complex that could be used in catalyzing the homogeneous hydrogenation of carboxylic acid with ammonia borane (hydrogen source) to synthesize primary alcohols. Various aromatic and aliphatic carboxylic acids with diverse functional groups were transformed to respective alcohols in moderate to high yields. The process can be easily scaled up (TON up to 14545) and exhibits a high compatibility with different sensitive functional groups, including fluorine, chlorine, bromine, iodine, hydroxyl, cyano and nitro groups. IMesCuCl/NH ₃·BH ₃ combination can selectively reduce aromatic and aliphatic esters. Mechanistic studies indicate that Cu-H species produced in situ are the active intermediates.

Comprehensive Summary:Salimabromide, a unique and scarce marine tetracyclic polyketide, was synthesized in both racemic and optically active forms. A novel carboxylic acid-directed method for tandem oxidative difunctionalization of olefins was developed, whereby the formation of bridged butyrolactone and enone moieties occurs concurrently. Density functional theory (DFT) calculations indicate that this reaction follows a [3+2] process rather than the [2+2] process. In the meantime, the distinctive benzo-fused [4.3.1] carbon skeleton and highly hindered vicinal quaternary stereocenters were simultaneously constructed through a challenging intramolecular Giese-Baran radical cyclization. Furthermore, deuterium kinetic isotopic effects were utilized to enhance the efficacy of this pivotal step. This represents a new illustration of the application of kinetic isotope effects in natural product synthesis. Then, the short asymmetric synthesis of (+)-salimabromide (13 or 15 steps) was accomplished by combing this method with rhodium-catalyzed enantioselective hydrogenation of a cycloheptenone derivative (97% ee) or conjugate addition of an aryl boronic acid with 2-cyclohepten-1-one (> 99% ee).

Comprehensive Summary:Spin crossover (SCO), characterized by distinct high-spin (HS) and low-spin (LS) states, has potential applications in memory, electronic, and electroluminescent devices. The OFF/ON switching of SCO is crucial for obtaining bistable magnetic properties. However, there are few strategies for achieving this switching. Herein, based on a ligand chemical doping strategy, we report an Fe(III) solid solution that can be prepared using a ligand chemical doping strategy, enabling not only the OFF/ON switching of SCO but also the fine-tuning of the spin transition temperature ( T _c) within a 45 K range near room temperature. The experimental results show that when the polar ligand doping ratio reaches 20%, SCO behavior is triggered, and the crystal phase transforms significantly, becoming loose and flexible. Furthermore, T _c can be continuously regulated as the ligand-doping ratio increases. Density functional theory (DFT) calculations reveal that solid packing-induced molecular distortion blocks SCO, whereas loosely flexible packing triggers SCO via fluorinated ligand chemical doping.

Comprehensive Summary:Enhancing the DNA toolbox with innovative photochemical reactions is pivotal for advancing nucleic acid-based technologies. Aldehyde groups, versatile bioorthogonal handles for imine formation under acidic conditions, are particularly valuable due to their roles in nucleic acid epigenetics. Here, we present the first photocatalytic on-DNA aldehyde allylation, enabling precise DNA functionalization under mild, neutral aqueous conditions. Our approach utilizes a photocatalytic polarity-reversal reaction between DNA-conjugated benzaldehydes and allyl sulfones. This reaction demonstrates exceptional chemoselectivity while preserving DNA integrity. By varying allyl sulfones, we achieve site-specific labeling of non-native DNA with the aldehyde group and cross-linking with DNA-bearing allyl sulfones. Furthermore, our method facilitates selective labeling and pull-down enrichment of 5-formylpyrimidine nucleotides among complex cellular DNA. This photocatalytic on-DNA aldehyde transformation expands the limited bioorthogonal photochemical toolboxes, providing novel avenues for functionalizing both non-native and native aldehyde modifications on DNA.

Comprehensive Summary:We reviewed works on radical borylation reactions since 2020 from two aspects. 1. Borylation from alkyl or aryl radicals: This approach involves the generation of alkyl or aryl radicals from various precursors such as halides and carboxylic acids, followed by their reaction with diboron reagents to form boron esters. 2. Borylation from boron-centered radicals: This approach involves generating boron-centered radicals, which then react with substrates to achieve borylation.