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Bioactive thionic compounds and aromatic glycosides from Ligusticum chuanxiong 被引量:7
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作者 Xu Zhang Bing Han +3 位作者 Ziming Feng Jianshuang Jiang Yanan Yang Peicheng Zhang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2018年第5期818-824,共7页
Three new thionic compounds,(S)-2-(2-carboxyl-2-hydroxyethylthio)-ferulic acid(1),(E)-2-methoxy-4-(3-(methylsulfonyl)prop-1-en-1-yl)phenol(2), and thiosenkyunolide C(3), together with two new aromatic glycosides(4 and... Three new thionic compounds,(S)-2-(2-carboxyl-2-hydroxyethylthio)-ferulic acid(1),(E)-2-methoxy-4-(3-(methylsulfonyl)prop-1-en-1-yl)phenol(2), and thiosenkyunolide C(3), together with two new aromatic glycosides(4 and 5) were isolated from the rhizome of Ligusticum chuanxiong Hort. Two known compounds(6 and 7) were also obtained. Their structures were elucidated based on extensive spectroscopic data(UV, IR, 1D and 2D NMR, and HR-ESI-MS). Furthermore the absolute configurations were established by comparison of their calculated and experimental circular dichroism spectra and by a dimolybdenum tetraacetate [Mo_2(AcO)_4]-induced circular dichroism procedure. All compounds were evaluated against lipopolysaccharide(LPS)-induced NO production in BV2 cells, and compounds 4 and 5 showed strong inhibitory activities with IC_(50) values of 2.03 and 3.09 μmol/L, respectively(positive control curcumin, IC_(50)=6.17 μmol/L). In addition, compound 1 showed weak proteintyrosine phosphatase-1 B(PTP1B) inhibitory activity. 展开更多
关键词 Ligusticum chuanxiong Hort. thionic COMPOUNDS AROMATIC GLYCOSIDES ANTI-INFLAMMATORY NATURAL PRODUCTS
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大气中甲酸硫酸酐增强新粒子形成机制的理论研究
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作者 李欣炘 安国策 +4 位作者 宋小鸣 倪爽 白凤杨 潘秀梅 赵震 《高等学校化学学报》 北大核心 2026年第3期64-73,共10页
三氧化硫(SO3)和甲酸(FA)可以快速反应形成甲酸硫酸酐(FSA),与公认的成核前驱体硫酸(SA)相比,FSA具有较低的饱和蒸汽压和较多的分子间相互作用位点,对大气新粒子形成(NPF)具有潜在贡献,然而,其成核能力尚不清楚.本文通过密度泛函理论评... 三氧化硫(SO3)和甲酸(FA)可以快速反应形成甲酸硫酸酐(FSA),与公认的成核前驱体硫酸(SA)相比,FSA具有较低的饱和蒸汽压和较多的分子间相互作用位点,对大气新粒子形成(NPF)具有潜在贡献,然而,其成核能力尚不清楚.本文通过密度泛函理论评估了FSA与大气中常见的62种物质的成核能力,并将其与其母体化合物甲酸和典型成核前驱体硫酸的成核潜力进行了对比,整体评估了FSA对新粒子形成的潜在贡献及大气影响.结果表明,FSA和大气中的常见单体均可自发形成二聚体,且在与含胺基的18种物质形成的二聚体团簇内部发生了质子转移,其中,FSA与单乙醇胺(MEA)二体团簇的吉布斯自由能(ΔG)值最负,表明MEA促进FSA的初始成核能力最强.其次,基于形成的最稳定团簇FSA-MEA、FSA的成核前驱体FA和SA分别与MEA形成的二聚体团簇FA-MEA和SA-MEA,探究了团簇的水合作用及吸湿性规律,发现随着水分子(n=0~6)的增多,团簇的稳定性增加,在不同的湿度条件下,二聚体水合物对湿度的敏感性顺序为SA-MEA>FSA-MEA>FA-MEA.随着尺寸的增大,团簇的各向同性平均极化率、瑞利光散射强度均呈线性增加,其顺序为FSA-MEA>SA-MEA>FA-MEA,表明FSA-MEA增强大气气溶胶的消光特性能力强于FA-MEA和SA-MEA,对大气可见度产生不利的影响. 展开更多
关键词 甲酸硫酸酐 二聚体 大气气溶胶 水合团簇 成核能力
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