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Structure elucidation of plumerubradins A-C:Correlations between^(1)H NMR signal patterns and structural information of[2+2]-type cyclobutane derivatives
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作者 Yu Xiong Li-Jun Hu +7 位作者 Jian-Guo Song Di Zhang Yi-Shuang Peng Xiao-Jun Huang Jian Honga Bin Zhu Wen-Cai Ye Ying Wang 《Chinese Chemical Letters》 2025年第5期369-374,共6页
[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereoche... [2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives. 展开更多
关键词 Plumeria rubra CYCLOBUTANE Biomimetic semisynthesis MicroED QM-HiFSA Empirical rule for structure elucidation
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Structural elucidation of a new cembranoid diterpene from the Chinese soft coral Sarcophyton sp.
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作者 别玮 邓志威 +1 位作者 徐岷涓 林文翰 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第3期221-224,共4页
To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elu... To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elucidated on the basis of extensive spectral data (IR, MS, 1 D- and 2D-NMR) analysis by comparing with literature data. A new cembranoid diterpene namely sarcophyolide A (1), together with 7a, 8β-dihydroxydeepoxysarcophine (2) were isolated from this species. The cembranoid diterpenes with 7-1actone could be chemotaxonomic markers of Sarcophyton sp. 展开更多
关键词 Sarcophyton sp. Cembranoid diterpene Sarcophyolide A Structural elucidation
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Neurofibrillary tangles in Alzheimer's disease: elucidation of the molecular mechanism by immunohistochemistry and tau protein phospho-proteomics 被引量:4
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作者 athanasios metaxas stefan j.kempf 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第10期1579-1581,共3页
As a key contributor to memory storage, the synapse is one of the earliest affected neuronal components in Alzheimer's disease (AD). Under physiological conditions, the synaptic con- nections between neurons underg... As a key contributor to memory storage, the synapse is one of the earliest affected neuronal components in Alzheimer's disease (AD). Under physiological conditions, the synaptic con- nections between neurons undergo activity-dependent func- tional and morphological re-organisation. This dynamic, 'plastic' neural ability critically depends on the structural integrity of the synapse. Thus, proteins that are implicated in preserving the organisation and dynamics of synaptic connections, including microtubules of the cytoskeleton and associated proteins, have attracted much focus for their involvement in the malfunction- ing AD synapse. 展开更多
关键词 Neurofibrillary tangles in Alzheimer’s disease elucidation of the molecular mechanism by immunohistochemistry and tau protein phospho-proteomics NFT
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STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM(LOUR.)SKEELS Ⅲ.The structural elucidation of homo-and zeta-clausenamide(1) 被引量:3
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作者 Ming He YANG Yan Yong CHEN Liang HUANG Institute of Materia Medica,Chinese Academy of Medical Sciences 1 Xian Nong Tan St.,Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期291-292,共2页
The structures of two novel lactams isolated from Clausena lansium were elucidated mainly on the bases of their spectral data. They are homoclausenamide(1),a -lactam,and zetaclausenamide(4), an eight-membered ring lac... The structures of two novel lactams isolated from Clausena lansium were elucidated mainly on the bases of their spectral data. They are homoclausenamide(1),a -lactam,and zetaclausenamide(4), an eight-membered ring lactam. 展开更多
关键词 The structural elucidation of homo-and zeta-clausenamide STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM LOUR SKEELS
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ISOLATION AND STRUCTURE ELUCIDATION OF A NOVEL STEROL FROM THE SOUTH CHINA SEA SPONGE DYSIDEA SP. 被引量:3
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作者 Yong Li ZHONG Jing Yu SU Long Mei ZENG Department of Chemistry,Zhongshan University,Guangzhou,510275 Wei SHEN Qi Wen WANG State Key Laboratory of Bioorganic and Natural Products Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Science,Shanghai,200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期981-982,共2页
A novel and unusual sterol with unsaturation in the△^(5(14)) position,5α-cholesta-8(14),24(25)-diene-3β,6α-diol 1,was isolated from the South China Ses sponge Dysidea sp.The structure and relative stereochemistry ... A novel and unusual sterol with unsaturation in the△^(5(14)) position,5α-cholesta-8(14),24(25)-diene-3β,6α-diol 1,was isolated from the South China Ses sponge Dysidea sp.The structure and relative stereochemistry of 1 was established by spectral analysis and comparison to the spectral data of known sterols. 展开更多
关键词 ISOLATION AND STRUCTURE elucidation OF A NOVEL STEROL FROM THE SOUTH CHINA SEA SPONGE DYSIDEA SP 二七 SEA
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ISOLATION, STRUCTURE ELUCIDATION AND SYNTHESIS OF A NEW PRENYLATED FLAVONOL, MAACKIAFLAVONOL, FROM MAACKIA TENUIFOLIA 被引量:2
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作者 Jian Hua SHEN, Lan WANG and Bing Nan ZHOU State Key Laboratory for New Drug Research, Shanghai Institute of Materia Medica, Academia Sinica, Shanghai 200031 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第8期629-630,共2页
A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, I... A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis. 展开更多
关键词 ISOLATION MAACKIAFLAVONOL STRUCTURE elucidation AND SYNTHESIS OF A NEW PRENYLATED FLAVONOL FROM MAACKIA TENUIFOLIA
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STRUCTURAL ELUCIDATION AND SYNTHESIS OF ASTERBATANOSIDE A FROM ASTER BATANFENSIS
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作者 Yu SHAO Yun Long LI and Bing Nan ZHOU(Shanghai Institute of Materia Medica,Academia sinica Shanghai 200031) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第8期675-678,共4页
A new p-acetylphenyl glycoside,asterbatanoside A has been isolated from the roots of Aster batangensis, and its structure has been elucidated as p-hydroxyacetophenone- -O-α-D-xylopyranosyl-(1,6) -β-D-glucopyranosid... A new p-acetylphenyl glycoside,asterbatanoside A has been isolated from the roots of Aster batangensis, and its structure has been elucidated as p-hydroxyacetophenone- -O-α-D-xylopyranosyl-(1,6) -β-D-glucopyranoside by chemical and spectral means.For the confirmation of this structure. the synthesis of this compound was also reported in this paper. 展开更多
关键词 ASTERBATANOSIDE SYNTHESIS BATANFENSIS elucidation FROM OF AND
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Isolation and Structure Elucidation of an Antifungal Antibiotics A73 Produced by a Soil Fungus Strain No.131
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作者 YANG Jun QI Xiu-lan +2 位作者 SHAO Gang YAO Xin-sheng Susumu Kitanaka 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第1期85-88,共4页
IntroductionMorphologicaldeformationofmyceliaorconidiaofmicroorganisms,suchascurling,sweling,hyper-divergenc... IntroductionMorphologicaldeformationofmyceliaorconidiaofmicroorganisms,suchascurling,sweling,hyper-divergency,beadformation,a... 展开更多
关键词 Antifungal antibiotics ISOLATION Structure elucidation A73
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THE STRUCTURE ELUCIDATION OF A NEW BIS-ENTKAURANE COMPOUND, ISODOPHARICIN E, ISOLATED FROM ISODON PHARICUS (PRAIN) MURATA.
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作者 Zhi Min WANG Pei Yuan CHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期847-848,共2页
On the basis of spectroscopic evidence (MS, ~1HNMR, ^(13)CNMR, CD, ~1H-~1H and ~1H-^(13)C cosy NMR) and chemical synthesis, the structure of isodopharicin E (1), isolated from the dry leaves and tender branches of Iso... On the basis of spectroscopic evidence (MS, ~1HNMR, ^(13)CNMR, CD, ~1H-~1H and ~1H-^(13)C cosy NMR) and chemical synthesis, the structure of isodopharicin E (1), isolated from the dry leaves and tender branches of Isodon pharicus (Prain) Murata was elucidated as 3R, 3'R, 13S, 13'S-tetrahydroxy-11S, 11'S-diacetoxy(16S-O-15')-bisentkaur-15'-en-15-one. 展开更多
关键词 BIS ISOLATED FROM ISODON PHARICUS MURATA PRAIN THE STRUCTURE elucidation OF A NEW BIS-ENTKAURANE COMPOUND ISODOPHARICIN E
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STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM (LOUR.) SKEELS Ⅳ THE STRUCTURAL ELUCIDATION OF SECO-AND SECODEMETHYL-CLAUSENAMIDE
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作者 Ming He YANG and Liang HUANG Institute of Materia Medica, Chinese Academy of Medical Sciences 1 Xian Nong Tan St., Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期775-776,共2页
The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were ... The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were determined by degradation to be 3S4R. 展开更多
关键词 CHEN LOUR SKEELS STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM THE STRUCTURAL elucidation OF SECO-AND SECODEMETHYL-CLAUSENAMIDE
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Isolation and structural elucidation of the compounds from the fruits of Camptotheca acuminate
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作者 Jingxian Ren Zhuoyang Cheng +2 位作者 Huan He Xiaoxiao Huang Shaojiang Song 《Asian Journal of Traditional Medicines》 CAS 2021年第2期69-75,共7页
The fruit of Camptotheca acuminate is used as a traditional Chinese medicine.Eight compounds were isolated from the fruit of Camptotheca acuminate for the first time,including(+)-(S)-abscisic acid(1),blumenol A(2),(E)... The fruit of Camptotheca acuminate is used as a traditional Chinese medicine.Eight compounds were isolated from the fruit of Camptotheca acuminate for the first time,including(+)-(S)-abscisic acid(1),blumenol A(2),(E)-3-hydroxymegastigm-7-en-9-one(3),(-)-(3R)-3,5-dimethyl-8-methoxy-3,4-dihydroisocoumarin(4),(-)-(3R)-8-methoxy-3-methyl-3,4-dihydro-1H-isochromen-1-one(5),neocnidilide(6),(3S)-butylphthalide(7)and senkyunolide I(8).Their structures were determined by comprehensive spectroscopic methods,including HRESIMS and 1D NMR. 展开更多
关键词 Camptotheca acuminate separation and purification structure elucidation
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Diphenylemestrins A-E:diketopiperazine-diphenyl ether hybrids from Aspergillus nidulans
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作者 Aimin Fu Qin Li +7 位作者 Yang Xiao Jiaxin Dong Yuanyang Peng Yu Chen Qingyi Tong Chunmei Chen Yonghui Zhang Hucheng Zhu 《Chinese Journal of Natural Medicines》 2025年第6期727-732,共6页
A chemical investigation of secondary metabolites(SMs)from Aspergillus nidulans resulted in the identification of five novel dioxopiperazine(DKP)-diphenyl ether hybrids,designated as diphenylemestrins A-E(1-5).These c... A chemical investigation of secondary metabolites(SMs)from Aspergillus nidulans resulted in the identification of five novel dioxopiperazine(DKP)-diphenyl ether hybrids,designated as diphenylemestrins A-E(1-5).These compounds 1-5 represent the first known dimers combining DKP and diphenyl ether structures,with compound 4 featuring an uncommon dibenzofuran as the diphenyl ether component.The structural elucidation and determination of absolute stereochemistry were accomplished through spectroscopic analysis and electronic circular dichroism(ECD)calculations.Notably,diphenylemestrin C(3)exhibited moderate cytostatic activity against NB4 cells,with a half maximal inhibitory concentration(IC50)value of 21.99μmol·L-1,and induced apoptosis at higher concentrations. 展开更多
关键词 Chemical constituents Biological activity Aspergillus nidulans Dioxopiperazines Structure elucidation.
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习近平经济思想的体系化建构和学理化阐释
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作者 洪向华 解超 《大连理工大学学报(社会科学版)》 北大核心 2025年第6期1-10,共10页
习近平经济思想是一个内涵丰富、体系严整、特征鲜明、准确严谨的科学理论体系。其基本内容以“七个坚持”为方法论主线,以“十三个方面”为实践展开,并在概念范畴上呈现层次分明、紧密联结的特征,在命题判断上呈现阐明本质、科学准确... 习近平经济思想是一个内涵丰富、体系严整、特征鲜明、准确严谨的科学理论体系。其基本内容以“七个坚持”为方法论主线,以“十三个方面”为实践展开,并在概念范畴上呈现层次分明、紧密联结的特征,在命题判断上呈现阐明本质、科学准确的特征,在逻辑结构上呈现主线清晰、布局严整的特征,充分彰显出其作为当代马克思主义政治经济学理论最新成果的体系性和科学性。在学理层面,习近平经济思想作为理论、历史与实践的有机统一,其将贯穿经济社会发展全过程的“新发展理念”作为理念主线,将体现经济关系本质的核心范畴而构建的范畴体系作为逻辑主线,并遵循“一般—特殊—具体”的分析方式,形成了以党的领导为根本保证、以人民为中心为根本立场、以“三新一高”为实践纽带、以基本经济制度和国家重大战略等作为重要抓手、以强调统筹发展和安全为重要保障的理论框架,并以正确的工作策略和方法论为指引,整体呈现出显著的科学性、实践性、人民性和开放性的鲜明特征。以习近平经济思想为指导,构建中国经济学自主知识体系已成为一项战略任务。当前的关键在于通过构建中国自主的经济学解释框架,推动实现从“概念”到“体系”的“术语革命”,最终形成具有中国特色、中国风格、中国气派的经济学理论体系,从而为全球经济发展贡献中国智慧。 展开更多
关键词 习近平经济思想 体系化建构 学理化阐释 新发展理念
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中国译者文化身份的内涵衍生及高校翻译教学研究
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作者 任婷 钱春花 《芜湖职业技术学院学报》 2025年第1期73-77,共5页
个体的文化身份往往随时代价值观的变化而不断演变。在文化自信的时代背景下,译者文化身份的内涵发生了新的衍生,中国译者文化身份承担三重角色:价值观念的传承者、语言文化的阐释者及话语权的构建者。这三种角色的内涵与关系也为高校... 个体的文化身份往往随时代价值观的变化而不断演变。在文化自信的时代背景下,译者文化身份的内涵发生了新的衍生,中国译者文化身份承担三重角色:价值观念的传承者、语言文化的阐释者及话语权的构建者。这三种角色的内涵与关系也为高校翻译教学提出了新的要求、提供了新的思路:高校翻译教学应增强文化认同教育、深入开展汉语语言文化课程、实施多议题翻译实践,以加强中华思想文化术语翻译教学。 展开更多
关键词 文化自信 译者 文化身份 价值观念 阐释 话语权 翻译教学
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话语体系建构视域下中国特色术语翻译的原则与实现维度
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作者 胡冬林 张德让 《呼伦贝尔学院学报》 2025年第3期29-33,43,共6页
术语具有话语体系建构的功能,术语翻译服务对外话语体系建构,能够为国家争取话语权,但术语翻译后在目标语境未必一定流通。为了促进被译术语有效流通,对外构建中国话语体系,应将中国特色术语翻译与传播融通,关照译者、受众、译法等多个... 术语具有话语体系建构的功能,术语翻译服务对外话语体系建构,能够为国家争取话语权,但术语翻译后在目标语境未必一定流通。为了促进被译术语有效流通,对外构建中国话语体系,应将中国特色术语翻译与传播融通,关照译者、受众、译法等多个维度。就译法而言,可通过文内阐释补充必要信息、解决术语内涵迻译不充分的问题,具体包括以“括注”细化阐释信息、以“功能词”引导阐释信息、以“定语从句”续写阐释信息、以“破折号”凸显阐释信息、以“背景描述”前置阐释信息。 展开更多
关键词 话语体系 中国特色术语 传播 实现维度 文内阐释
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白术根中4个新倍半萜类化合物 被引量:2
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作者 周刚刚 刘佳佳 +5 位作者 王纪琼 刘辉 廖志华 王国伟 陈敏 孟凡成 《药学学报》 北大核心 2025年第1期179-184,共6页
对苍术属植物白术Atractylodes macrocephala Koidz.的干燥根进行化学成分研究。运用正相硅胶、ODS、半制备HPLC等色谱方法从白术乙酸乙酯部位分离纯化得到4个倍半萜类化合物,采用1D和2D NMR、HR-ESIMS、IR、UV、CD等技术手段鉴定其结... 对苍术属植物白术Atractylodes macrocephala Koidz.的干燥根进行化学成分研究。运用正相硅胶、ODS、半制备HPLC等色谱方法从白术乙酸乙酯部位分离纯化得到4个倍半萜类化合物,采用1D和2D NMR、HR-ESIMS、IR、UV、CD等技术手段鉴定其结构为白术酮A(1)、9β-羟基紫菀内酯(2)、白术内酯H(3)、白术内酯J(4)。化合物1~4均为新的倍半萜类化合物,其中化合物1具有一个少见的6/7双环骨架结构。 展开更多
关键词 白术 化学成分 倍半萜 提取分离 结构鉴定
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Advancing network pharmacology with artificial intelligence:the next paradigm in traditional Chinese medicine 被引量:1
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作者 Xin Shao Yu Chen +4 位作者 Jinlu Zhang Xuting Zhang Yizheng Dai Xin Peng Xiaohui Fan 《Chinese Journal of Natural Medicines》 2025年第11期1358-1376,共19页
Network pharmacology has gained widespread application in drug discovery,particularly in traditional Chinese medicine(TCM)research,which is characterized by its“multi-component,multi-target,and multi-pathway”nature.... Network pharmacology has gained widespread application in drug discovery,particularly in traditional Chinese medicine(TCM)research,which is characterized by its“multi-component,multi-target,and multi-pathway”nature.Through the integration of network biology,TCM network pharmacology enables systematic evaluation of therapeutic efficacy and detailed elucidation of action mechanisms,establishing a novel research paradigm for TCM modernization.The rapid advancement of machine learning,particularly revolutionary deep learning methods,has substantially enhanced artificial intelligence(AI)technology,offering significant potential to advance TCM network pharmacology research.This paper describes the methodology of TCM network pharmacology,encompassing ingredient identification,network construction,network analysis,and experimental validation.Furthermore,it summarizes key strategies for constructing various networks and analyzing constructed networks using AI methods.Finally,it addresses challenges and future directions regarding cell-cell communication(CCC)-based network construction,analysis,and validation,providing valuable insights for TCM network pharmacology. 展开更多
关键词 Traditional Chinese medicine Network pharmacology Artificial intelligence Efficacy evaluation Mechanism elucidation Network construction Network analysis
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垫状卷柏中1个新骨架的炔酚类化合物
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作者 吴永平 段金廒 曹园 《中草药》 北大核心 2025年第1期39-43,共5页
目的研究垫状卷柏Selaginella pulvinata全草的化学成分。方法采用硅胶、Sephadex LH-20等多种柱色谱方法进行分离纯化,应用理化方法和波谱分析进行结构鉴定;采用MTT法测定化合物对人非小细胞肺癌A549细胞的抑制活性。结果从垫状卷柏全... 目的研究垫状卷柏Selaginella pulvinata全草的化学成分。方法采用硅胶、Sephadex LH-20等多种柱色谱方法进行分离纯化,应用理化方法和波谱分析进行结构鉴定;采用MTT法测定化合物对人非小细胞肺癌A549细胞的抑制活性。结果从垫状卷柏全草的95%乙醇提取物的醋酸乙酯部位分离得到1个新骨架类型的炔酚类化合物,鉴定为9-羟基-3,4,13-三(4-羟基苯基)-7H-二苯并[gh,pqr]四苯基-7-酮(1);化合物1对A549细胞显示出较强的抑制活性,其半数抑制浓度(half maximal inhibitory concentration,IC_(50))为(16.29±1.44)μg/mL。结论化合物1为新化合物,命名为卷柏新酮,具有选择性细胞毒活性。 展开更多
关键词 垫状卷柏 炔酚类化合物 卷柏新酮 结构鉴定 肿瘤细胞毒活性
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采用液质联用技术定性分析松叶鸡蛋参根的化学成分
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作者 赵文慧 窦志扬 +5 位作者 强巴 吾坚 白玛卓玛 刘广学 蔡少青 徐风 《广西植物》 北大核心 2025年第3期585-605,共21页
为阐明藏药鸡蛋参[植物松叶鸡蛋参(Codonopsis convolvulacea var.pinifolia)的根]的化学成分,该文采用超高效液相色谱-四级杆飞行时间质谱联用(UHPLC-Q-TOF-MS/MS)技术对其化学成分进行定性分析。采用Waters ACQUITY UPLC BEH C_(18)(... 为阐明藏药鸡蛋参[植物松叶鸡蛋参(Codonopsis convolvulacea var.pinifolia)的根]的化学成分,该文采用超高效液相色谱-四级杆飞行时间质谱联用(UHPLC-Q-TOF-MS/MS)技术对其化学成分进行定性分析。采用Waters ACQUITY UPLC BEH C_(18)(1.7μm,2.1 mm×150 mm)色谱柱,以0.1 mmol·L^(-1)乙酸铵水溶液(A)-乙腈(B)为流动相,流速0.3 mL·min^(-1),进样体积3μL,柱温40℃。质谱使用ESI离子源,采用负离子检测模式,扫描范围为m/z 100~1800(MS)、m/z 50~1800(MS/MS)。根据化合物一级质谱中的准分子离子推测其分子式,根据化合物二级质谱中的特征碎片离子推测其可能的结构片段及分子结构,再结合对照品对比和文献检索,进行结构鉴定。结果表明:(1)首次从松叶鸡蛋参中鉴定出56种化合物,其中含氮类成分6种、苯丙素类成分6种、木脂素类成分22种、黄酮类成分2种、有机酸类成分8种、糖苷或其他类成分12种;采用对照品比对指认了其中11种成分。(2)首次发现木脂素类和苯丙素类化合物为松叶鸡蛋参根的主要成分,并推导出其裂解途径。该研究结果表明,应用UHPLC-Q-TOF-MS/MS技术能够快速高效地初步阐明松叶鸡蛋参根的化学成分,为藏药鸡蛋参的质量标准、体内过程及药效物质等研究提供了化学基础。 展开更多
关键词 松叶鸡蛋参 UHPLC-Q-TOF-MS/MS 化学成分 结构解析 裂解途径
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缬草内生真菌Aspergillus sp.FH-2中1个新的丁烯内酯类化合物
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作者 王鑫 禹梦欣 +7 位作者 吴怡轩 赵丽媛 张可桢 李玉泽 张东东 王薇 宋小妹 樊浩 《中草药》 北大核心 2025年第18期6515-6520,共6页
目的研究缬草Valeriana officinalis内生真菌Aspergillus sp.FH-2大米高盐培养基中抗真菌次生代谢产物。方法采用硅胶和ODS柱色谱以及半制备液相色谱等方法进行分离纯化,并结合其理化性质及核磁共振(NMR)、红外(IR)、质谱(MS)等波谱学... 目的研究缬草Valeriana officinalis内生真菌Aspergillus sp.FH-2大米高盐培养基中抗真菌次生代谢产物。方法采用硅胶和ODS柱色谱以及半制备液相色谱等方法进行分离纯化,并结合其理化性质及核磁共振(NMR)、红外(IR)、质谱(MS)等波谱学技术进行结构解析。采用菌丝生长速率法测定了所有化合物对木瓜炭疽病菌Colletotrichum gloeosporioides的抗真菌活性。结果从Aspergillus sp.FH-2菌株的醋酸乙酯提取部位分离得到8个化合物,分别鉴定为3-methoxy-4'-hydroxyphenyl-5-[4''-hydroxy-3''-(9''-hydroxy-3''-methylbutyl)benzyl]-2-oxo-2,5-dihydrofuran-5-carboxylate(1)、桔青霉三酚A(2)、大黄素(3)、7-hydroxy-3-(2-hydroxypropyl)-5-methyl-isochromen-1-one(4)、2,5-dimethyl-7-hydroxychromone(5)、2,4-dihydroxy-3-methylacetophenone(6)、2,4-dihydroxy-5-methylacetophenone(7)和4-acetyl-resorcinol(8)。其中,化合物1、2、4、7对木瓜炭疽病菌抑制作用的半数有效浓度(half-maximal effective concentration,EC50)值分别为85.14、66.18、81.45、74.68μg/mL。结论化合物1为新化合物,命名为3-甲氧基-曲霉丁烯内酯B(3-methoxy-aspernolide B)。抗真菌活性研究表明,化合物1、2、4和7对木瓜炭疽病菌表现出中等抑制效果。 展开更多
关键词 缬草 Aspergillus sp.FH-2 分离纯化 结构鉴定 3-甲氧基-曲霉丁烯内酯B 抗真菌
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