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1.
Pseuduvarines A (1) and B (2), two new dioxoaporphine alkaloids with an amino moiety, were isolated from the stem bark of Pseuduvaria rugosa and their structures were elucidated by combination of 2D-NMR spectroscopic analysis. Pseuduvarines A (1) and B (2) showed cytotoxicity against MCF7, HepG2, and HL-60 (1: IC??, 0.9, 21.7, and >50.0 μM, respectively, 2: IC?? >50.0, 15.7, and 12.4 μM, respectively).  相似文献   
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Five new limonoids, ceramicines E-I (1-5), have been isolated from the bark of Chisocheton ceramicus. The structures and relative stereochemistry of them were fully elucidated based on 1D- and 2D-NMR data. Ceramicines E-I (1-5) exhibited moderate cell growth inhibitory activities on a range of cell lines (HL-60, A549, MCF7, and HCT116). The absolute structure of previously isolated ceramicine B (6) was also elucidated by circular dichroism (CD) and X-ray analysis.  相似文献   
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Eight new guaipyridine sesquiterpene alkaloids, rupestines F-M (1-8) were isolated from the leaves of Artemisia rupestris and their structures were elucidated on the basis of 2D-NMR data. The absolute configurations of 1-8 have been assigned by comparison of their experimental and calculated circular dichroism (CD) spectra.  相似文献   
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A new alkylbenzoquinone named embeliquinone (1) together with five known compounds, lupeol (2), 3-O-[6′-O-palmitoyl-β-d-glucosyl]-spinasta-7,22(23)-diene (3), quercetin (4), (2S,3S,4R,8E)-2-[(2′R)-2′-hydroxy-heneicosanoylamino]-heneicosane-1,3,4-triol-8-ene (5), and β-sitosterol-3-O-β-d-glucopyranoside (6) were isolated from the MeOH leaf extract of Embelia rowlandii by using repeated open column chromatography techniques. The structure of the new compound was characterized by analyses of 1D- and 2D-NMR, and MS data. Embeliquinone (1) had moderate anti-cell proliferation activity against A549 cell line with the IC50 value of 21.8 μM. In addition, 1 exhibited weak antibacterial activities against Klebsiella pneumoniae and Staphylococcus aureus with an MIC value of 206.0 μM in both cases.  相似文献   
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Six new diterpenoids, sabiperones A-F (1-6) have been isolated from the aerial part of Juniperus sabina. Their structures were elucidated by spectroscopic methods including 2D NMR techniques. Sabiperone F showed moderate cell growth inhibitory activities against five human cancer cell lines.  相似文献   
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Four new compounds, 2-hydroxy-6-(12′-hydroxyheptadec-13′(E)-en-1-yl)benzoic acid (1), 2-hydroxy-6-(13′-hydroxyheptadec-11′(E)-en-1-yl)benzoic acid (2), 2-hydroxy-6-(10′-hydroxypentadec-11′(E)-en-1-yl)benzoic acid (3), and 2-hydroxy-6-(11′-hydroxypentadec-9′(E)-en-1-yl)benzoic acid (4) were isolated from the leaves of Ginkgo biloba and the structures of new ginkgolic acids were deduced on the basis of spectroscopic methods and chemical means. Compounds 1 and 2, and 3 and 4 examined as an inseparable mixture of hydroxyl and double bond positional isomers, were ultimately defined by total synthesis. Compounds 14 showed moderate lipid droplets accumulation inhibitory activity on mouse pre-adipocyte cell line, MC3T3-G2/PA6.  相似文献   
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A novel C16N2-type Lycopodium alkaloid consisting of a quinolizidine with a 6-dimethylaminohexyl side chain, hupermine A (1), was isolated from the club moss of Huperzia phlegmaria, and the structure and relative stereochemistry were elucidated on the basis of spectroscopic data.  相似文献   
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Based on a hydro-inspired azimuthally symmetric emission function, we analyze the HBT radius Rs and the single-particle transverse momentum spectra in Au+Au collisions measured by the STAR Collaboration at SNN = 200 GeV. The results show that consistent assumptions about transverse density (and/or flow profile) in the calculation of the HBT radius Rs and single-particle spectral analyses play an important role for understanding the size of the freeze-out source.  相似文献   
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