Search

Porous imidazole polymerized ionic liquids (PILs-Im) with fast Li+ diffusion kinetics and numerous molecular pores have been used as anodes in lithium-ion batteries for the first time.

Metals play essential roles in life by coordination with small molecules, proteins, and nucleic acids. Although the coordination of copper ions in many proteins and methanobactins is known, the coordination chemistry of Cu(II) in natural products and their biological functions remain underexplored. Herein, we report the discovery of a Cu(II)-binding natural product, chalkophomycin (CHM, 1), from Streptomyces sp. CB00271, featuring an asymmetric square-coordination system of a bidentate diazeniumdiolate and a conjugated 1H-pyrrole 1-oxide-oxazoline. The structure of 1 may inspire the synthesis of Cu(II) chelators against neurodegenerative diseases or Cu(II)-based antitumor therapeutics.

Inducible nitric oxide synthase (iNOS) produces NO from l-arginine and plays critical roles in inflammation and immune activation. Selective and potent iNOS inhibitors may be potentially used in many indications, such as rheumatoid arthritis, pain, and neurodegeration. In the current study, five new compounds, including a dibenzo-α- pyrone derivative ellagic acid B (5) and four α-pyrones diaporpyrone A–D (9–12), together with three known compounds (6–8), were isolated from the endophytic fungus Diaporthe sp. CB10100. The structures of these new natural products were unambiguously elucidated using NMR, HRESIMS or electronic circular dichroism calculations. Ellagic acid B (5) features a tetracyclic 6/6/6/6 ring system with a fused 2H-chromene, which is different from ellagic acid (4) with a fused 2H-chromen-2-one. Both 2-hydroxy-alternariol (6) and alternariol (7) reduced the expression of iNOS at protein levels in a dose-dependent manner, using a lipopolysaccharide (LPS)-induced RAW264.7 cell models. Also, they decreased the protein expression levels of pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin-6 and monocyte chemotactic protein 1. Importantly, 6 and 7 significantly reduced the production of NO as low as 10 μM in LPS-induced RAW264.7 cells. Molecular docking of 6 and 7 to iNOS further suggests that both of them may interact with iNOS. Our study suggests that 6 and 7, as well as the alternariol scaffold may be further developed as potential iNOS inhibitors.

Metal-organic frameworks (MOFs) with intrinsic pores and redox organic ligands/metallic ions have been viewed as the promising anodes with high capacity in lithium ion batteries (LIBs). However, conventional MOFs faces the disadvantages of poor electron conductivity and weak coordinate bond between organic ligands and central metal ions, inhibiting the application in LIBs. In this study, a conductive MOFs of Ni3(HITP)2 has been fabricated by reacting the strong-field ligand of 2,3,6,7,10,11-hexaiminotriphenylene (HITP) with Ni2+. The as-prepared Ni3(HITP)2 presents the spindle-like shape that are regular arranged by multi-nano fibers. While utilized in LIBs, Ni3(HITP)2 can deliver the reversible capacity of 703 mAh g−1 at 50 mA g−1 with almost no capacity fading. According to the theoretical calculation and XPS results, both amino groups in ligand and Ni2+ ions have participated in the redox reaction during the charge/discharge processes. The superior Li+ storage performance of Ni3(HITP)2 are contributed by the intercalation capacity of the redox groups and capacitance of the molecular pores.