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石松子粉最小点火能试验研究 被引量:20
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作者 黄丽媛 曹卫国 +3 位作者 徐森 张建新 秋珊珊 潘峰 《爆破器材》 CAS 北大核心 2012年第5期9-11,16,共4页
采用1.2 L哈特曼管最小点火能测试装置,研究了中位径为32μm的石松子粉的最小点火能量随粉尘浓度、点火延时以及喷粉压力之间的变化规律。试验结果表明:在环境温度为(25±5)℃,环境湿度为30%±5%的条件下,石松子粉的最佳着火浓... 采用1.2 L哈特曼管最小点火能测试装置,研究了中位径为32μm的石松子粉的最小点火能量随粉尘浓度、点火延时以及喷粉压力之间的变化规律。试验结果表明:在环境温度为(25±5)℃,环境湿度为30%±5%的条件下,石松子粉的最佳着火浓度750 g/m3,最佳点火延时为90 ms,最佳喷粉压力为0.8 MPa,此时石松子粉的最小点火能达到极小值。在相同的实验条件下有电感的点火方式比无电感的点火方式所需的能量要小。在有电感存在的情况下,石松子粉的最小点火能为10 mJ;在无电感存在的情况下,石松子粉的最小点火能为15 mJ,说明石松子粉对电火花较敏感。 展开更多
关键词 石松子粉 哈特曼管 最小点火能 点火延时 喷粉压力
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玉柏石松三萜成分研究(英文) 被引量:9
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作者 邓铁忠 艾勇 +1 位作者 陈玉 杨光忠 《药学学报》 CAS CSCD 北大核心 2009年第8期891-894,共4页
为了研究玉柏石松全草的三萜类成分,运用正相和反相硅胶柱色谱技术对玉柏石松的乙酸乙酯提取物进行分离纯化,并运用波谱技术对其结构进行鉴定。共分离得到5个三萜类化合物,其结构分别鉴定为3β,19α-dihydroxy-20β-acetate-serrat-14-e... 为了研究玉柏石松全草的三萜类成分,运用正相和反相硅胶柱色谱技术对玉柏石松的乙酸乙酯提取物进行分离纯化,并运用波谱技术对其结构进行鉴定。共分离得到5个三萜类化合物,其结构分别鉴定为3β,19α-dihydroxy-20β-acetate-serrat-14-en-21β-ol(1),serratenediol(2),α-onocerin(3),26-nor-8-oxo-α-onocerin(4),(3β,8β,14α,21α)-26,27-dinoronocerane-3,8,14,21-tetrol(5)。其中化合物1为新的石松型三萜化合物,化合物5为首次从该植物中分离得到。 展开更多
关键词 石松属 玉柏石松 石松三萜
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石松生物碱成分的研究进展 被引量:9
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作者 袁珊琴 栾新慧 《军事医学科学院院刊》 CSCD 北大核心 1999年第1期58-61,共4页
综述了1984年以来石松生物碱成分的研究进展,并对Selagine(huperzineA)型生物碱的光谱学特征。
关键词 石松碱 生物碱类 研究进展
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Huperzine V,A New Lycopodium Alkaloid from Huperzia serrata 被引量:8
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作者 HuiQingLIU ChangHengTAN ShanHaoJIANG DaYuanZHU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第3期303-304,共2页
Huperzine V, a new Lycopodium alkaloid, was isolated from the whole plant of Huperzia serrata, and the absolute stereochemistry was determined by X-ray crystallographic analysis.
关键词 Huperzine V Huperzia serrata lycopodium alkaloids.
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石松子粉尘爆炸危险性及抑爆研究 被引量:10
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作者 彭于怀 黄丽媛 +3 位作者 曹卫国 郑俊杰 卑凤利 潘峰 《爆破器材》 CAS 北大核心 2014年第6期16-21,共6页
为了研究粒径对石松子粉尘爆炸危险性的影响,采用Godbert-Greenwald(G-G)炉和20 L球爆炸装置对石松子粉尘云进行了试验,分析了粒径对爆炸特性的影响,并探讨了Si O2和NH4H2PO4对石松子粉的抑爆效果。结果表明:粒径越小的粉尘着火温度越低... 为了研究粒径对石松子粉尘爆炸危险性的影响,采用Godbert-Greenwald(G-G)炉和20 L球爆炸装置对石松子粉尘云进行了试验,分析了粒径对爆炸特性的影响,并探讨了Si O2和NH4H2PO4对石松子粉的抑爆效果。结果表明:粒径越小的粉尘着火温度越低,潜在危险性更大;粒径小于48μm的粉尘,在质量浓度为750 g/m3时达到最大爆炸指数22.61 MPa·m/s,其爆炸危险性为Ⅱ级,相比于粒径小于75μm的粉尘,爆炸危险性更高;添加Si O2和NH4H2PO4后,能够显著降低石松子粉的爆炸压力和爆炸指数;与Si O2相比,NH4H2PO4具有更好的抑爆效果。 展开更多
关键词 石松子粉 粉尘爆炸 着火温度 爆炸压力 爆炸指数 抑爆
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石松子粉粉尘爆炸试验研究 被引量:7
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作者 秋珊珊 曹卫国 +2 位作者 黄丽媛 张建新 潘峰 《爆破器材》 CAS 北大核心 2012年第3期16-18,共3页
该论文采用20 L球形爆炸测试装置对粒径在75μm以下的石松子粉的粉尘爆炸下限浓度、爆炸压力和爆炸指数随粉尘浓度的变化规律等进行了研究。研究结果表明:石松子粉粉尘爆炸下限浓度在20~40 g/m3之间,在粉尘浓度相对较低的60~500 g/m3... 该论文采用20 L球形爆炸测试装置对粒径在75μm以下的石松子粉的粉尘爆炸下限浓度、爆炸压力和爆炸指数随粉尘浓度的变化规律等进行了研究。研究结果表明:石松子粉粉尘爆炸下限浓度在20~40 g/m3之间,在粉尘浓度相对较低的60~500 g/m3时,粉尘的爆炸压力和爆炸指数随着粉尘浓度的提高而急速上升,在浓度为500 g/m3时达到最大,此时最大爆炸压力为0.69 MPa,爆炸指数为17.20 MPa.m/s;继续增加粉尘浓度,爆炸压力和爆炸指数略有下降,但仍维持在较高值;并判定石松子粉粉尘爆炸危险性分级为Ⅰ级。 展开更多
关键词 石松子粉 粉尘爆炸 爆炸下限浓度 最大爆炸压力 爆炸指数
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甲烷/石松子粉尘混合体系爆炸下限的变化规律 被引量:7
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作者 喻健良 纪文涛 +2 位作者 孙会利 闫兴清 张新燕 《爆炸与冲击》 EI CAS CSCD 北大核心 2017年第6期924-930,共7页
基于标准20 L球形爆炸装置,在相同测试条件下,分别测量了石松子粉尘、甲烷和不同浓度配比的甲烷/石松子粉尘混合体系爆炸下限,并将测试结果与Le Chatelier’s law、Bartknecht curve、Jiang method等混合体系爆炸下限预测结果进行了对... 基于标准20 L球形爆炸装置,在相同测试条件下,分别测量了石松子粉尘、甲烷和不同浓度配比的甲烷/石松子粉尘混合体系爆炸下限,并将测试结果与Le Chatelier’s law、Bartknecht curve、Jiang method等混合体系爆炸下限预测结果进行了对比。结果表明:低于爆炸下限的甲烷和低于爆炸下限的石松子粉尘混合后仍具有爆炸危险性。石松子粉尘爆炸下限随混合体系中甲烷体积分数的增高而减小。Le Chatelier’s law、Bartknecht curve、Jiang method均不能准确预测甲烷/石松子粉尘混合体系爆炸下限。Le Chatelier’s law对甲烷体积分数φ与甲烷爆炸下限φ_L之比φ/φ_L<0.5的混合体系爆炸下限的预测值偏小,而对φ/φ_L>0.5的混合体系预测值偏大;Bartknecht curve在预测φ/φ_L>0.5的混合体系爆炸下限时适用性较好,而对于φ/φ_L<0.5的混合体系预测值偏小;Jiang method不适用于预测甲烷/石松子粉尘混合体系爆炸下限。 展开更多
关键词 粉尘爆炸 爆炸下限 气粉混合体系 石松子 甲烷
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Carbonic anhydrase-like enzymes in the formation of Lycopodium alkaloid
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作者 DONG Huiwen GE Huiming 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第3期193-194,共2页
Plant alkaloids,renowned for their structural diversity and bioactivity,are prominent in both modern and traditional medicine[1].Unraveling the intricacies of plant alkaloid biosynthesis could pave the way for the dis... Plant alkaloids,renowned for their structural diversity and bioactivity,are prominent in both modern and traditional medicine[1].Unraveling the intricacies of plant alkaloid biosynthesis could pave the way for the discovery of new natural products and pathways.It may also shed light on the roles of existing pathways in host biology and provide valuable tools for metabolic engineering in plants and microbes[2].Unlike other major classes of plant natural products,such as terpenoids and polyketides,the formation of alkaloid scaffolds does not conform to a uniform chemical theme or depend on a singular enzyme class[3].A case in point is the Lycopodium alkaloids in the Lycopodiaceae family,where the enzymes responsible for their core scaffold construction remain unidentified[4]. 展开更多
关键词 lycopodium alkaloid Carbonic anhydrase-like enzymes BIOSYNTHESIS
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甲烷/石松子两相混合体系爆炸强度参数 被引量:6
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作者 喻健良 孙会利 +3 位作者 纪文涛 闫兴清 张新燕 蔡林锋 《爆炸与冲击》 EI CAS CSCD 北大核心 2018年第1期92-97,共6页
基于改进的20 L球形粉尘爆炸装置,在相同初始条件下分别测量了甲烷、石松子粉尘和甲烷/石松子两相混合体系的爆炸压力、爆炸压力上升速率和爆炸指数等参数,系统研究了甲烷/石松子粉尘两相混合体系爆炸特性变化规律。结果表明:甲烷的添... 基于改进的20 L球形粉尘爆炸装置,在相同初始条件下分别测量了甲烷、石松子粉尘和甲烷/石松子两相混合体系的爆炸压力、爆炸压力上升速率和爆炸指数等参数,系统研究了甲烷/石松子粉尘两相混合体系爆炸特性变化规律。结果表明:甲烷的添加能显著提高低质量浓度石松子粉尘爆炸压力而降低高质量浓度石松子粉尘爆炸压力;甲烷对石松子粉尘最大爆炸压力没有显著影响,但能显著提高石松子粉尘最大爆炸压力上升速率。甲烷/石松子粉尘混合体系爆炸指数高于单相石松子粉尘爆炸指数,但甲烷/石松子粉尘混合体系和单相石松子粉尘爆炸指数均低于单相甲烷爆炸指数。工业生产过程中应避免粉尘混入可燃气体以降低粉尘爆炸危险性。 展开更多
关键词 粉尘爆炸 气/粉尘两相体系 爆炸强度 甲烷 石松子
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Huperzine W,a Novel 14 Carbons Lycopodium Alkaloid from Huperzia serrata 被引量:3
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作者 ChangHengTAN XiaoQiangMA 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期331-332,共2页
Huperzine W, a novel 14 carbons Lycopodium alkaloid, was isolated from the whole plant of Huperzia serrata, and its stucture was determined by spectroscopic analysis.
关键词 Huperzine W Huperzia serrata lycopodium alkaloids.
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石松科生物碱的集群合成研究进展
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作者 贺菲菲 李辉林 厍学功 《中国科学:化学》 CAS CSCD 北大核心 2023年第3期439-446,共8页
石松生物碱数目繁多,结构复杂,通常具有抑制乙酰胆碱酯酶的活性.该类天然产物的高效合成是有机合成化学家们研究的热点之一,本文综述了近五年来石松生物碱集群合成研究方面的代表性成果.
关键词 石松 生物碱 集群合成 天然产物
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中国石松目植物的分类系统 被引量:4
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作者 杨纯瑜 《军事医学科学院院刊》 CSCD 北大核心 1990年第4期269-275,共7页
本文根据中国石松目植物的形态演化及各科属间的进化关系,提出了中国石松目植物的分类系统。结果在石杉科的石杉属中建立了锯齿组和无齿组,马尾杉属中建立了腋生组、马尾组和绳索组;在石松科的石松属中建立了杉蔓石松组、石松组和玉柏... 本文根据中国石松目植物的形态演化及各科属间的进化关系,提出了中国石松目植物的分类系统。结果在石杉科的石杉属中建立了锯齿组和无齿组,马尾杉属中建立了腋生组、马尾组和绳索组;在石松科的石松属中建立了杉蔓石松组、石松组和玉柏石松组;并考证了各科属的文献来源及学名的沿革,阐明了国产石松目植物的种数、分布及资源情况,为进一步开发利用本目植物提供了分类学基础。 展开更多
关键词 石松目植物 分类系统 石杉科
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Incorporation of 3-dimensional lycopodium with hydrophobic nature and interconnected nano-channels into polyvinylidene fluoride membranes for desalination applications by vacuum membrane distillation
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作者 Saeed Seraj Toraj Mohammadi Maryam Ahmadzadeh Tofighy 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2023年第9期1162-1182,共21页
In the present research,for the first time,lycopodium as a novel nanofiller was incorporated into a polyvinylidene fluoride matrix to fabricate lycopodium/polyvinylidene fluoride flat-sheet membrane for desalination a... In the present research,for the first time,lycopodium as a novel nanofiller was incorporated into a polyvinylidene fluoride matrix to fabricate lycopodium/polyvinylidene fluoride flat-sheet membrane for desalination applications by vacuum membrane distillation process.The prepared lycopodium/polyvinylidene fluoride membranes and lycopodium were characterized by field emission scanning electron microscopy,X-ray diffraction,Fourier transform infrared,energy dispersive X-ray,and mapping analyses.Water contact angle and liquid entry pressure measurements were also performed.Response surface methodology was applied to optimize membrane structure and performance.The optimized lycopodium/polyvinylidene fluoride membrane exhibits superior performance compared to the neat polyvinylidene fluoride membrane in terms of flux,salt rejection,water contact angle,and hydrophobicity.In vacuum membrane distillation experiments,using a 15000 ppm NaCl solution as a feed at 70℃,the neat polyvinylidene fluoride membrane,optimum membrane,and agglomerated membrane(with high lycopodium loading)demonstrated 3.80,25.20,and 14.83 LMH flux and 63.30%,99.99%,99.96%salt rejection,respectively.This improvement in flux and salt rejection of the optimized membrane was related to the presence of lycopodium with hydrophobic nature and interconnected nano-channels in membrane structure.It was found that lycopodium,as the most hydrophobic material,effectively influences the membrane performance and structure for membrane distillation applications. 展开更多
关键词 lycopodium hoprobhobicity vucuum embrane distillation DESALINATION
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Lyconadins G and H,Two Rare Lyconadin-Type Lycopodium Alkaloids from Lycopodium complanatum 被引量:1
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作者 Jin-Tang Cheng Zhi-Jun Zhang +4 位作者 Xiao-Nian Li Li-Yan Peng Huai-Rong Luo Xing-De Wu Qin-Shi Zhao 《Natural Products and Bioprospecting》 CAS 2016年第6期279-284,共6页
Two rare lyconadin-type Lycopodium alkaloids,lyconadins G(1)and H(2),together with four known ones(3–6),were isolated from Lycopodium complanatum.The structures were determined on the basis of their spectroscopic ana... Two rare lyconadin-type Lycopodium alkaloids,lyconadins G(1)and H(2),together with four known ones(3–6),were isolated from Lycopodium complanatum.The structures were determined on the basis of their spectroscopic analyses,and the absolute configuration of 1 was established by an X-ray crystallographic analysis.It is the first time to establish the absolute configuration of lyconadin-type Lycopodium alkaloid by an X-ray diffraction experiment.In addition,these findings may provide more information for the biosynthesis of lyconadins. 展开更多
关键词 lycopodium alkaloids lycopodium complanatum Lyconadin
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石杉碱O的结构鉴定 被引量:4
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作者 王保德 滕宁宁 朱大元 《有机化学》 SCIE CAS CSCD 北大核心 2000年第5期812-814,共3页
蛇足石杉[Huperziaserrata(Thunb.)Trev]中,R_f与石杉碱甲相近部位分离得到一个新生物碱,经IR,MS,1D和2DNMR确定了其化学结构,为一个有内氢键烯醇型新的lycopodine类生物碱,命名为石杉碱O(Huperzine O)。
关键词 蛇足石杉 石杉碱O 中药 生物碱 结构鉴定
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Chemical constituents and biological activities of lycophytes and ferns 被引量:1
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作者 ZHU Qin-Feng ZHAO Qin-Shi 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第12期887-891,共5页
Lycophytes and ferns are unique and charismatic members of many terrestrial ecosystems and occupy the pivotal position in land plant origin and evolution.The Chinese lycophytes and ferns flora,with approximately 2000 ... Lycophytes and ferns are unique and charismatic members of many terrestrial ecosystems and occupy the pivotal position in land plant origin and evolution.The Chinese lycophytes and ferns flora,with approximately 2000 species,contributes a substantial component to the global lycophytes and ferns diversity,with estimates of 12000 species.Among them,about 433 species are medicinally recorded and researches based on their phytochemical properties are important topics in natural medicines.This paper reviewed the research history and current status of chemical constituents and biological activities of lycophytes and ferns,which had highlighted the research progress of our group. 展开更多
关键词 LYCOPHYTES FERNS Chemical constituents Biological activities lycopodium alkaloids
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Lycoplanines B-D,Three Lycopodium Alkaloids from Lycopodium complanatum 被引量:1
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作者 Zhi-Jun Zhang Qin-Feng Zhu +2 位作者 Jia Su Xing-De Wu Qin-Shi Zhao 《Natural Products and Bioprospecting》 CAS 2018年第3期177-182,共6页
A novel Ci7N Lycopodium alkaloid(LA),lycoplanine B(1),containing an unusual formyl group,along with two new LAs,lycoplanines C(2)and D(3),were isolated from the whole plant of Lycopodium complanatum.Their structures w... A novel Ci7N Lycopodium alkaloid(LA),lycoplanine B(1),containing an unusual formyl group,along with two new LAs,lycoplanines C(2)and D(3),were isolated from the whole plant of Lycopodium complanatum.Their structures were elucidated by extensive NMR techniques,including 1D-and 2D-NMR experiments,as well as comparing their spectral data with those of the known analogues.A possible biogenetic pathway for 1 was also proposed. 展开更多
关键词 lycopodium complanatum Lycoplanines lycopodium alkaloids Anti-AChE activity
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Ethanol Extract of Lycopodium serratum Thunb. Attenuates Lipopolysaccharide-Induced C6 Glioma Cells Migration via Matrix Metalloproteinase-9 Expression 被引量:1
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作者 Ju-Yeon Park Hyuck Kim +3 位作者 Dong-Woo Lim Jai-Eun Kim Won-Hwan Park Sun-Dong Park 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第11期860-866,共7页
Objectives: To elucidate how ethanol extract of L. serratum(ELS) could exert anti-migratory effects on glioma with the suppression of nuclear factor kappa B(NF-κB) downstream pathway. Methods: Cell viability of... Objectives: To elucidate how ethanol extract of L. serratum(ELS) could exert anti-migratory effects on glioma with the suppression of nuclear factor kappa B(NF-κB) downstream pathway. Methods: Cell viability of ELS on C6 glioma was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. Nitric oxide(NO) assay and 2',7'-dichlorofluorescin diacetate(DCFH-DA) assay were applied to measure NO production and reactive oxygen species(ROS) generation on lipopolysaccharide(LPS)-induced C6 glioma cells. NF-κB, mitogen-activated protein kinase(MAPK), inducible nictric oxide synthase(i NOS) and cyclooxygenase-2(COX-2) protein were determined by Western blot. Wound healing assay was used to investigate the inhibitory effect of ELS on fetal bovine serum(FBS)-induced migration and matrix metalloproteinase(MMP)-9 and-2 activity was examined by zymography. Results: ELS suppressed LPS-induced phosphorylation of extracellular signal-regulated kinase(ERK), c-Jun N-terminal kinase(JNK), and p38 through inhibiting the expression of chemokine CCL2(or monocyte chemoattractant protein-1, MCP-1). In addition, ELS inhibited the expression of i NOS, COX-2, and the production of NO by LPS in C6 glioma cells. ELS also significantly decreased serum-induced migration of C6 glioma cells in scratch wound healing in a dose-dependent manner(P〈0.01). The activity of MMP-9 and-2 were also significantly attenuated by ELS with LPS treatment(P〈0.01). Conclusion: Our results suggest that downregulation of MMP-9 gene expression might be involved in the anti-migration effect of ELS against LPS-induced C6 glioma cells. 展开更多
关键词 lycopodium serratum Thunb LIPOPOLYSACCHARIDE matrix metalloproteinase MIGRATION C6 glioma cell
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Lycopodine-Type Alkaloids from Lycopodium japonicum 被引量:3
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作者 Juan He Xing-De Wu +6 位作者 Fei Liu Yu-Cheng Liu Li-Yan Peng Yu Zhao Xiao Cheng Huai-Rong Luo Qin-Shi Zhao 《Natural Products and Bioprospecting》 CAS 2014年第4期213-219,共7页
Three new lycopodine-type alkaloids,4a-hydroxyanhydrolycodoline(1),4a,6a-dihydroxyanhydrolycodoline(2),and 6-epi-8b-acetoxylycoclavine(3),and an artifact,lycoposerramine G nitrate(4),along with seventeen related known... Three new lycopodine-type alkaloids,4a-hydroxyanhydrolycodoline(1),4a,6a-dihydroxyanhydrolycodoline(2),and 6-epi-8b-acetoxylycoclavine(3),and an artifact,lycoposerramine G nitrate(4),along with seventeen related known compounds,were isolated from the club moss Lycopodium japonicum Thunb.ex Murray(Lycopodiaceae).Their structures were elucidated by extensive spectroscopic methods as well as X-ray analysis.Compounds 1–4 were evaluated for their acetylcholine esterase inhibitory activity. 展开更多
关键词 lycopodium japonicum Lycopodine-type alkaloids 4a-Hydroxyanhydrolycodoline 4a 6a-Dihydroxyanhydrolycodoline 6-epi-8b-Acetoxylycoclavine Lycoposerramine G nitrate
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Two Novel Hydroperoxylated Lycopodium Alkaloids from Huperzia serrata 被引量:3
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作者 谭昌恒 马晓强 +2 位作者 周慧 蒋山好 朱大元 《Acta Botanica Sinica》 CSCD 2003年第1期118-121,共4页
Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid f... Two novel hydroperoxylated Lycopodium alkaloids, 11alpha-hydroperoxyphlegmariurine B (1) and 7-hydroperoxyphlegmariurine B (2), along with a known compound, phlegmanurine B (3), were isolated from the total alkaloid fraction of the Chinese medicinal herb Huperzia serrata (Thunb.) Trev. Their structures and relative configurations were elucidated on the basis of spectroscopic analyses. 展开更多
关键词 Huperzia serrata lycopodium alkaloids 11 alpha-hydroperoxyphlegmariurine B 7-hydroperoxyphlegmaniurine B
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