Publications by authors named "Kang Ding"

Five new C-diterpenoid alkaloids carmaloidlines A-E (1-5) and a known C-diterpenoid alkaloid (6) were isolated from the lateral roots of Aconitum carmichaelii Debeaux. Their structures were determined through spectrometric analysis and quantum chemical calculations. Meanwhile, the plausible biosynthetic pathways of 1-6 were also discussed.

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A novel rearranged C-diterpenoid alkaloid, carmiseconapline A (), featuring a unique 10,20:11,12-di--napelline skeleton with a fused 5/6/5/6/7 pentacyclic ring system, was isolated from Debeaux. Compound exhibited remarkable antidepressive activity, being twice as potent as fluoxetine (10 mg/kg) at 0.06 mg/kg in mice.

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Systematic exploration of the hadal zone, Earth's deepest oceanic realm, has historically faced technical limitations. Here, we collected 1,648 sediment samples at 6-11 km in the Mariana Trench, Yap Trench, and Philippine Basin for the Mariana Trench Environment and Ecology Research (MEER) project. Metagenomic and 16S rRNA gene amplicon sequencing generated the 92-Tbp MEER dataset, comprising 7,564 species (89.

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Here, we introduce the Mariana Trench Environment and Ecology Research (MEER) project, which provides the first systematic view of the ecosystem in the hadal zone.

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Depression is a chronic mental disorder characterized by persistent low mood and loss of interest, often associated with dysregulation of neuroinflammatory pathways. Inhibition of NOD-like receptor protein 3 (NLRP3), a key mediator of neuroinflammation, is a promising strategy for alleviating depressive symptoms by modulating inflammatory responses in the brain. Seven polycyclic polyprenylated acylphloroglucinols (PPAPs), including six new hyperioxides A-F (1-6) and furohyperforin (7) were isolated from St.

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Impulsive feature (IF) response is an essential indicator for rolling bearing fault. However, it is overwhelmed by strong noise and difficult to extract in real scenes. Although deep learning-based methods are powerful in feature extraction, their logic and extracting principles possess weak interpretability and credibility.

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Daphnane diterpenoids, as one of the representative types of diterpenoid compounds with rich structural diversity and significant biological activities, have an uncommon 5/7/6 tricyclic skeleton mainly found in species of Thymelaeaceae and Euphorbiaceae families. Due to the unique peculiarity of the framework and remarkable pharmacological activities, over the past three decades, novel structures have been continuously discovered and more structural subtypes have been derived. However, there is always a lack of a unified and convincing structural classification strategy for the summary of daphnane diterpenoids, which affects the in-depth and systematic research of pharmaceutical chemists and pharmacologists.

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Article Synopsis
  • Establishing urban greenspaces improves air quality and cools urban areas, but the specific mechanisms behind these benefits, particularly the structural characteristics of plant communities, are not fully understood.
  • Field experiments conducted in Beijing on 108 plant communities showed that most plant setups (90.91%) provide both pollution retention and cooling effects, influenced by their three-dimensional structure.
  • The study revealed that herbaceous layers mainly contribute to pollution retention, while tree layers are crucial for cooling, with a notable trade-off between the two benefits; trees help maintain pollution retention by regulating temperature changes.
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P-stereogenic phosphorus compounds are essential across various fields, yet their synthesis via enantioselective P-C bond formation remains both challenging and underdeveloped. We report the first copper-catalyzed enantioselective hydrophosphorylation of alkynes, facilitated by a newly designed chiral 1,2-diamine ligand. Unlike previous methods that rely on kinetic resolution with less than 50 % conversion, our approach employs a distinct dynamic kinetic asymmetric transformation mechanism, achieving complete conversion of racemic starting materials.

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C_(20)-diterpenoid alkaloids are mainly distributed in plants of genus Aconitum, Delphinium, and Consolida in the Ranunculaceae. Their chemical structures are mainly categorized into nine types such as atisines, denudatines, hetidines, and hetisines. Bioactivity studies have shown that C_(20)-diterpenoid alkaloids have exhibited superior anti-tumor, analgesic, antiarrhythmic, and anti-inflammatory effects.

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The chemical constituents from Cornus officinalis were isolated and purified by various techniques such as macroporous adsorption resin, silica gel, octadecylsilyl(ODS), Sephadex LH-20 column chromatography and preparative high-performance liquid chromatography(HPLC). The structures of the isolates were determined by a combination of spectroscopic techniques such as high-resolution electrospray ionization mass spectrometry(HR-ESI-MS), one-dimensional(1D) and two-dimensional(2D) nuclear magnetic resonance(NMR) spectroscopy. Ten compounds were isolated from the aqueous extract of C.

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Catkins, as a significant source of plant-caused pollution, disrupts daily human activities and industrial processes. Despite their impact, catkins have not been included in official environmental quality monitoring indicators, leading to a deficiency in scientifically rigorous collection and monitoring methodologies, as well as a lack of ecological prevention and management strategies. In this study, we introduced a fine-scale monitoring approach for catkins.

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Article Synopsis
  • - The identification of key ecological restoration areas in cities is essential for ensuring urban ecological security, particularly in resource-driven towns like Handan City, where abandoned mining sites play a significant role.
  • - The study classified these mining sites based on their ecological functions and spatial significance, using specific indicators related to water and soil conservation and biodiversity to evaluate their importance for ecological protection.
  • - The findings revealed that 73 out of 204 abandoned mining sites in Handan, covering a total area of 1500.9 hm, are critical for ecological restoration, particularly in areas with serious environmental issues but significant potential for transformation and value extension in the mining sector.
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Quasi-two-dimensional (Q-2D) perovskites show great potential in the field of photonic and optoelectronic device applications. However, defects and local lattice dislocation still limit performance and stability improvement by nonradiative recombination, unpreferred phase distribution, and unbonded amines. Here, a low-temperature synergistic strategy for both reconstructing and solidifying the perovskite top and buried interface is developed.

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Six new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperidiones A-F (1-6), were obtained from Hypericum perforatum L. Their structures were characterized via extensive spectroscopic analyses, the circular dichroism data of the in situ formed [Mo(OCOCH)] complexes, the nuclear magnetic resonance calculation with DP4 probability analysis, and the calculated electronic circular dichroism (ECD) spectra. Compounds 1-6 are bicyclic polyprenylated acylphloroglucinols with a major bicyclo[3.

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In vitro maturation (IVM) and cryopreservation of goat oocytes are important for establishing a valuable genetic bank for domesticated female animals and improving livestock reproductive efficiency. C-Phycocyanin (PC) is a Spirulina extract with antioxidant, antiinflammatory, and radical scavenging properties. However, whether PC has positive effect on goat oocytes IVM or developmental competence after vitrification is still unknown.

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Article Synopsis
  • Industrialization along critical rivers like the middle Yangtze has led to serious environmental and public health concerns due to soil heavy metal pollution.
  • A study focusing on eight industrial parks revealed that heavy metals such as nickel, cadmium, and copper are most significantly present above normal levels, with their sources identified as various industrial processes, including chemical manufacturing and mechanical production.
  • The findings underline the severe ecological and health risks posed by these metals, particularly cadmium and mercury, which are major contributors to environmental hazards and carcinogenic threats, emphasizing the need for advanced analytical methods to assess and address these issues.
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The application of ionic liquids and deep eutectic solvents offers a promising opportunity for a more environmentally friendly and straightforward chitin purification process from crustacean shells. Nonetheless, the insufficient recyclability of these ionic solvents poses a challenge to the long-term sustainability of such extraction methods. Thus, there is a strong imperative to focus on employing easily recyclable ionic liquids for chitin isolation, enhancing the overall sustainability of the process.

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Background And Purpose: Ulcerative colitis (UC) is a global refractory disease characterized by recurrent episodes. Coptisine (COP) is an isoquinoline alkaloid derived from Coptis chinensis, which has strong anti-inflammatory activity. Macrophages are key cells mediating inflammation.

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  • Cornus officinalis Sieb. et Zucc. is a traditional Chinese medicinal plant featuring loganin, an active compound believed to help with depression, but its pharmacokinetics and brain distribution remain unclear.* -
  • The study aimed to analyze the pharmacokinetic properties and tissue distribution of loganin in rats using a validated UPLC-MS/MS method for precise measurement.* -
  • Results indicated that loganin is quickly absorbed (peak time ~40 min) and eliminated (half-life ~50 min) in rats, with a 5.50% oral bioavailability and significant concentration found in the stomach.*
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The early Cambrian Qiongzhusi Formation shale is rich in organic matter and is a high-quality marine Source rock. However, the origin of Qiongzhusi Formation siliceous rocks is unknown, and the role of siliceous rocks in the process of organic matter enrichment or preservation is also lacking. This study combines thin section, scanning electron microscopy, SEM/EDS, major and trace element analysis, and N adsorption experiments to analyze and evaluate the shale of the Qiongzhusi Formation in the central region of the Sichuan Basin.

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Transition-metal-catalyzed enantioselective P-C cross-coupling of secondary phosphine oxides (SPOs) is an attractive method for synthesizing P-stereogenic phosphorus compounds, but the development of such a dynamic kinetic asymmetric process remains a considerable challenge. Here we report an unprecedented highly enantioselective dynamic kinetic intermolecular P-C coupling of SPOs and aryl iodides catalyzed by copper complexes ligated by a finely modified chiral 1,2-diamine ligand. The reaction tolerates a wide range of SPOs and aryl iodides, affording P-stereogenic tertiary phosphine oxides (TPOs) in high yields and with good enantioselectivity (average 89.

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Six undescribed macrocyclic daphnane orthoesters, stelleratenoids A-F (1-6), were isolated from the roots of Stellera chamaejasme L. Their structures were elucidated by extensive spectroscopic analyses, including HRESIMS and NMR spectra. Compound 1 features an unusual terminal double bond at C-2/C-19 in the 1α-alkyldaphnane lactone skeleton.

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