9 research outputs found

    Lithium–Sulfur Battery Cathode Enabled by Lithium–Nitrile Interaction

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    Lithium sulfide is a promising cathode material for high-energy lithium ion batteries because, unlike elemental sulfur, it obviates the need for metallic lithium anodes. Like elemental sulfur, however, a successful lithium sulfide cathode requires an inherent mechanism for preventing lithium polysulfide dissolution and shuttling during electrochemical cycling. A new scheme is proposed to create composites based on lithium sulfide uniformly dispersed in a carbon host, which serve to sequester polysulfides. The synthesis methodology makes use of interactions between lithium ions in solution and nitrile groups uniformly distributed along the chain backbone of a polymer precursor (e.g., polyacrylonitrile), to control the distribution of lithium sulfide in the host material. The Li<sub>2</sub>S–carbon composites obtained by carbonizing the precursor are evaluated as cathode materials in a half-cell lithium battery, and are shown to yield high galvanic charge/discharge capacities and excellent Coulombic efficiency, demonstrating the effectiveness of the architecture in homogeneously distributing Li<sub>2</sub>S and in sequestering lithium polysulfides

    Discovery and Characterization of Moracin C as an Anti-Gouty Arthritis/Hyperuricemia Candidate by Docking-Based Virtual Screening and Pharmacological Evaluation

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    In the present study, a natural product database of compounds associated with herbs traditionally verified to treat gout/hyperuricemia/arthritis was constructed. 3D-shape and docking-based virtual screening was conducted. To identify potential xanthine oxidase (XOD) inhibitors in the database, eight compounds with commercial availability were identified as high 3D-shape similarity with febuxostat (1), a known XOD inhibitor. Docking was used to further predict the possible interactions between XOD and these compounds. Moracin C (2), moracin D (3), and isoformononetin (8) exhibited higher docking scores and binding energies than other compounds. In vitro, 2 inhibited XOD with an IC50 value of 0.25 ± 0.14 μM, which is similar to that of 1 (0.16 ± 0.08 μM). In a hyperuricemic mouse model, 5–20 mg/kg 2 exhibited satisfying urate-lowering and XOD inhibitory effects. Compound 2 also exhibited antiarthritis activities. In RAW264.7 cells, 2 at 1–10 μM inhibited the expression of IL-1β and TNF-α induced by MSU. In an acute gouty arthritis model in SD rats, 5–20 mg/kg 2 significantly alleviated the toe swelling, inflammatory response, and dysfunction disorder caused by monosodium urate (MSU). Compound 2 inhibited serum IL-1β and TNF-α cytokines as well as reduced the expression of the NLRP3/ASC/caspase-1 inflammasome in joints. In summary, 2 was an effective compound for the treatment of hyperuricemia/gouty arthritis

    X‑ray Crystal Structure-Guided Discovery of Novel Indole Analogues as Colchicine-Binding Site Tubulin Inhibitors with Immune-Potentiating and Antitumor Effects against Melanoma

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    A series of novel indole analogues were discovered as colchicine-binding site inhibitors of tubulin. Among them, 3a exhibited the highest antiproliferative activity (average IC50 = 4.5 nM), better than colchicine (IC50 = 65.3 nM). The crystal structure of 3a in complex with tubulin was solved by X-ray crystallography, which explained the improved binding affinity of 3a to tubulin and thus its higher anticancer activity (IC50 = 4.5 nM) than the lead compound 12b (IC50 = 32.5 nM). In vivo, 3a (5 mg/kg) displayed significant antitumor efficacy against B16-F10 melanoma with a TGI of 62.96% and enhanced the antitumor efficacy of a small-molecule PD-1/PD-L1 inhibitor NP19 (TGI = 77.85%). Moreover, 3a potentiated the antitumor immunity of NP19 by activating the tumor immune microenvironment, as demonstrated by the increased tumor-infiltrating lymphocytes (TIL). Collectively, this work shows a successful example of crystal structure-guided discovery of a novel tubulin inhibitor 3a as a potential anticancer and immune-potentiating agent

    X‑ray Crystal Structure-Guided Discovery of Novel Indole Analogues as Colchicine-Binding Site Tubulin Inhibitors with Immune-Potentiating and Antitumor Effects against Melanoma

    No full text
    A series of novel indole analogues were discovered as colchicine-binding site inhibitors of tubulin. Among them, 3a exhibited the highest antiproliferative activity (average IC50 = 4.5 nM), better than colchicine (IC50 = 65.3 nM). The crystal structure of 3a in complex with tubulin was solved by X-ray crystallography, which explained the improved binding affinity of 3a to tubulin and thus its higher anticancer activity (IC50 = 4.5 nM) than the lead compound 12b (IC50 = 32.5 nM). In vivo, 3a (5 mg/kg) displayed significant antitumor efficacy against B16-F10 melanoma with a TGI of 62.96% and enhanced the antitumor efficacy of a small-molecule PD-1/PD-L1 inhibitor NP19 (TGI = 77.85%). Moreover, 3a potentiated the antitumor immunity of NP19 by activating the tumor immune microenvironment, as demonstrated by the increased tumor-infiltrating lymphocytes (TIL). Collectively, this work shows a successful example of crystal structure-guided discovery of a novel tubulin inhibitor 3a as a potential anticancer and immune-potentiating agent

    Largely Improved Creep Resistance and Thermal-Aging Stability of Eco-Friendly Polypropylene High-Voltage Insulation by Long-Chain Branch-Induced Interfacial Constraints

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    Polypropylene (PP)-based composites have attracted numerous attention as a replacement of prevailing cross-linked polyethylene (XLPE) for high-voltage insulation due to their ease of processing, recyclability, and excellent electrical performance. However, the poor resistances against high-temperature creep and thermal aging are obstacles to practical applications of PP-based thermoplastic high-voltage insulation. To address these problems, in this Letter, we synthesized an impact polypropylene copolymer (IPC) containing multifold long-chain branched (LCB) structures in phases, especially the interfaces between the PP matrix and the rubber phase. The results indicated that the structural stability of LCBIPC was significantly enhanced under extreme conditions. In comparison to IPC (without LCB structures), 24.1% less creep strain and 75.2% less unrecoverable deformation are achieved in LCBIPC at 90 °C. In addition, the thermal aging experiments were performed at 135 °C for 48 and 88 days for IPC and LCBIPC, respectively. The results show that the resistance against thermal aging was also enhanced in LCBIPC, which showed a 133% longer thermal aging life compared to IPC. Further results revealed that the interfacial layer between the PP matrix and the rubber phase was constructed in LCBIPC. The two phases are tightly linked by chemical bonds in LCB structures, leading to enforced constraints of the rubber phase at the micro level and better resistance performance against creep and thermal aging at the macro level. Evidently, the reported eco-friendly LCBIPC thermoplastic insulation shows great potential for applications in high-voltage cable insulation

    Discovery and Computational Studies of Potent Covalent Kinase Inhibitors with α‑Substituent Electrophiles Targeting Cysteine

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    Both reversible noncovalent inhibitors and irreversible covalent inhibitors targeting tyrosine kinases have their disadvantages. The reversible covalent inhibitors with electrophilic group cyanoacrylamide as warheads reacting with cysteine residues could solve the dilemmas. However, there are still several unresolved issues regarding the electrophilic groups. In this manuscript, a series of EGFR inhibitors with double electron-withdrawing substituents introduced into the Cα position on the olefin bond were designed and synthesized. The binding structures and characteristics of inhibitors with the kinase in both the first noncovalent binding phase and the second covalent binding step were explored and combined with molecular docking and molecular dynamics simulations. Then, the reverse β-elimination reactions of the thiol-Michael adducts were investigated by applying density functional theory calculations. In addition, the effects of different electrophilic substituents of Cα on the binding between the inhibitors and kinase were elucidated. The results suggested that the electrophilicity and size of the electron-withdrawing groups play an important role in the specific interactions during the reaction. The compounds with the electron-withdrawing groups that had medium electrostatic and steric complementarity to the kinase active site could cooperatively stabilize the complexes and showed relatively good potent activities in the kinase assay experiment. The mechanical and structural information in this study could enhance our understanding of the functioning of the electron-withdrawing groups in the covalent inhibitors. The results might help to design efficient cysteine targeting inhibitors in the future

    Discovery and Computational Studies of Potent Covalent Kinase Inhibitors with α‑Substituent Electrophiles Targeting Cysteine

    No full text
    Both reversible noncovalent inhibitors and irreversible covalent inhibitors targeting tyrosine kinases have their disadvantages. The reversible covalent inhibitors with electrophilic group cyanoacrylamide as warheads reacting with cysteine residues could solve the dilemmas. However, there are still several unresolved issues regarding the electrophilic groups. In this manuscript, a series of EGFR inhibitors with double electron-withdrawing substituents introduced into the Cα position on the olefin bond were designed and synthesized. The binding structures and characteristics of inhibitors with the kinase in both the first noncovalent binding phase and the second covalent binding step were explored and combined with molecular docking and molecular dynamics simulations. Then, the reverse β-elimination reactions of the thiol-Michael adducts were investigated by applying density functional theory calculations. In addition, the effects of different electrophilic substituents of Cα on the binding between the inhibitors and kinase were elucidated. The results suggested that the electrophilicity and size of the electron-withdrawing groups play an important role in the specific interactions during the reaction. The compounds with the electron-withdrawing groups that had medium electrostatic and steric complementarity to the kinase active site could cooperatively stabilize the complexes and showed relatively good potent activities in the kinase assay experiment. The mechanical and structural information in this study could enhance our understanding of the functioning of the electron-withdrawing groups in the covalent inhibitors. The results might help to design efficient cysteine targeting inhibitors in the future

    Discovery of Novel Potent and Fast BTK PROTACs for the Treatment of Osteoclasts-Related Inflammatory Diseases

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    Bruton’s tyrosine kinase (BTK) is an attractive target in inflammatory and autoimmune diseases. However, the effectiveness of BTK inhibitors is limited by side effects and drug resistance. In this study, we report the development of novel BTK proteolysis targeting chimeras (PROTACs) with different classes of BTK-targeting ligands (e.g., spebrutinib) other than ibrutinib. Compound 23 was identified as a potent and fast BTK PROTAC degrader, exhibiting outstanding degradation potency and efficiency in Mino cells (DC50, 4 h = 1.29 ± 0.3 nM, t1/2, 20 nM = 0.59 ± 0.20 h). Furthermore, compound 23 forms a stable ternary complex, as confirmed by the HTRF assay. Notably, 23 down-regulated the BTK-PLCγ2-Ca2+-NFATc1 signaling pathway activated by RANKL, thus inhibiting osteo­clasto­genesis and attenuating alveolar bone resorption in a mouse periodontitis model. These findings suggest that compound 23 is a potent and promising candidate for osteoclast-related inflammatory diseases, expanding the potential of BTK PROTACs

    Discovery of Novel Potent and Fast BTK PROTACs for the Treatment of Osteoclasts-Related Inflammatory Diseases

    No full text
    Bruton’s tyrosine kinase (BTK) is an attractive target in inflammatory and autoimmune diseases. However, the effectiveness of BTK inhibitors is limited by side effects and drug resistance. In this study, we report the development of novel BTK proteolysis targeting chimeras (PROTACs) with different classes of BTK-targeting ligands (e.g., spebrutinib) other than ibrutinib. Compound 23 was identified as a potent and fast BTK PROTAC degrader, exhibiting outstanding degradation potency and efficiency in Mino cells (DC50, 4 h = 1.29 ± 0.3 nM, t1/2, 20 nM = 0.59 ± 0.20 h). Furthermore, compound 23 forms a stable ternary complex, as confirmed by the HTRF assay. Notably, 23 down-regulated the BTK-PLCγ2-Ca2+-NFATc1 signaling pathway activated by RANKL, thus inhibiting osteo­clasto­genesis and attenuating alveolar bone resorption in a mouse periodontitis model. These findings suggest that compound 23 is a potent and promising candidate for osteoclast-related inflammatory diseases, expanding the potential of BTK PROTACs
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