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Professor Jia Chunsheng's instruction on clinical application of"elements for acupuncture effect orientation"in the Song to Elucidate Mysteries
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作者 Xian-Bing Hou Shu-Yan Liu Chun-Sheng Jia 《TMR Clinical Research》 2021年第1期15-19,共5页
Professor Jia Chunsheng is one of the sixth of old traditional Chinese medicine experts,and often instructs students in ordinary clinics to attach importance to learning and clinical practices of classic works.Now Pro... Professor Jia Chunsheng is one of the sixth of old traditional Chinese medicine experts,and often instructs students in ordinary clinics to attach importance to learning and clinical practices of classic works.Now Professor Jia Chunsheng selects a poet-Song to Elucidate Mysteries in the Guidelines of Acupuncture Classic by Dou Hanqing in the Jin and Yuan Dynasties,and requires the students to read carefully,investigate deeply,and apply at times;Moreover,Professor Jia Chunsheng discusses the"important factors to achieve good clinical therapeutic effects by acupuncture"contained in the Song to Elucidate Mysteries,in many aspects of understanding acupoint characteristics,defining clearly acupoint compatibility,selecting appropriate needling manipulation,how to determine needling depth,how to determine needling direction,how to determine needle retention time,and how to select acupuncture&moxibustion method,etc.Now they are discussed as follows,to discover and spread Dou's acupuncture technique and to increase clinical therapeutic effects. 展开更多
关键词 Jia Chunsheng APPRENTICE CLASSICS Dou Hanqing Song to elucidate Mysteries Therapeutic dose of acupuncture
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Reevaluating the role of skeletal muscle in amyotrophic lateral sclerosis pathogenesis:Insights from muscle-derived factors
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作者 Pablo Martinez Brigitte van Zundert Fernando J.Bustos 《Neural Regeneration Research》 2026年第7期2944-2945,共2页
Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease marked by motor neuron(MN)degeneration,neuromuscular junction disruption,and muscle atrophy,ultimately leading to paralysis and death.Despit... Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease marked by motor neuron(MN)degeneration,neuromuscular junction disruption,and muscle atrophy,ultimately leading to paralysis and death.Despite extensive research,no effective treatment exists,highlighting the need to elucidate mechanisms driving ALS pathogenesis.About 90%of ALS cases are sporadic ALS and lack a clear genetic cause;the remaining 10%are familial ALS,associated with mutations in over 25 genes.The most common mutations are in superoxide dismutase 1(SOD1)and C9ORF72,with rarer variants in FUS,TARDBP,TBK1,and VCP. 展开更多
关键词 amyotrophic lateral sclerosis als neurodegenerative disease elucidate mechanisms neuromuscular junction amyotrophic lateral sclerosis motor neuron muscle atrophyultimately junction disruptionand
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Characterization of Glutarimide Derivatives from Agrimonia pilosa-Associated Endophytic Streptomyces sp.YINM00048
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作者 Su Yuying Wang Yingfang +4 位作者 Yi Mengzhuo Zhao Lixing Li Jiaxuan Ma Ling Yin Min 《有机化学》 北大核心 2026年第1期289-294,共6页
Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 k... Two new glutarimide derivatives,2-hydroxy-3-[2-(2-hydroxy-3-methylphenyl-5-hydroxymethyl)-2-oxoethyl]glutarimide(1)and 2-hydroxy-3-[2-[2-hydroxy-3-hydroxymethyl-5-methylphenyl]-2-oxoethyl]glutarimide(2),along with 8 known compounds were isolated from the liquid fermentation broth of endophytic Streptomyces sp.YINM00048 obtained from Agrimonia pilosa.Their structures were elucidated through comprehensive spectroscopic analysis,including nuclear magnetic resonance,high-resolution mass spectrometry,and single-crystal X-ray diffraction,supported by time-dependent density functional theory(TDDFT)-electronic circular dichroism(ECD)calculations.Furthermore,compound 2 displayed weak cytotoxic activity against A549 and SMMC-7721 cell lines with IC50 values of 62.69 and 55.07μmol/L,respectively. 展开更多
关键词 Agrimonia pilosa endophytic Streptomyces glutarimide structural elucidation anti-tumor activity
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Discovery of A New Sesquiterpene-Lactone from Streptomyces aureus SP-371
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作者 Zhang Tao Ji Zhenyu +1 位作者 Tang Gongli Hou Xianfeng 《有机化学》 北大核心 2026年第2期689-692,共4页
new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The che... new sesquiterpene-lactone,designated as neopentalenolactone D1(1),was isolated from the fermentation cultures of Streptomyces aureus SP-371,which is known for producing agricultural-bactericide aureonuclemycin.The chemical structure of compound 1 was determined to be a neopentapyrrole natural product with a 5/5/6 tricyclic skeleton and one amide functional group,by using spectroscopic techniques such as nuclear magnetic resonance(1D/2D NMR)and high-resolution mass spectrometry(HR-ESI-MS).Its structural information indicates that it is probably the shunt product of neopentalenolactone biosynthetic pathway.In antibacterial activity evaluations,compound 1 demonstrated no inhibitory effects against the tested strains including Escherichia coli(DH5a),Staphylococcus aureus,and Bacillus subtilis under the experimental conditions. 展开更多
关键词 Streptomyces aureus sesquiterpene-lactone structural elucidation biosynthetic pathway
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Protein dynamics elucidated by NMR technique
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作者 Conggang Li Chun Tang Maili Liu 《Protein & Cell》 SCIE CSCD 2013年第10期726-730,共5页
In 1957,Christian Anfinsen postulated his famous dogma based on the study of ribonuclease(Sela et al.,1957),stating that the amino acid sequence of a protein determines its tertiary structure,a unique and kinetically ... In 1957,Christian Anfinsen postulated his famous dogma based on the study of ribonuclease(Sela et al.,1957),stating that the amino acid sequence of a protein determines its tertiary structure,a unique and kinetically accessible energy minimum,in a given environment.As a result,determination of a global energy minimum,or the most populated structure,has been the main focus of structural biology in the ensuing half a century.With more and more structures have been determined,people have gain some insights of why protein functions,but the detailed mechanisms and the function process,or how protein functions,remains elusive. 展开更多
关键词 elucidated STRUCTURE DYNAMICS
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From fragments to function:a review of AI-driven mass spectrometry and fragment-based strategies
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作者 Tianyi Ma Zhaoxin Xu +2 位作者 Yugang Lin Jie Liao Xiaohui Fan 《Acupuncture and Herbal Medicine》 2026年第1期28-41,共14页
Traditional Chinese medicine(TCM)possesses unique advantages in disease prevention and treatment,yet its inherent complexity and diversity pose tremendous challenges for structural elucidation,mechanism research,and b... Traditional Chinese medicine(TCM)possesses unique advantages in disease prevention and treatment,yet its inherent complexity and diversity pose tremendous challenges for structural elucidation,mechanism research,and bioactivity characterization.Highresolution mass spectrometry(HRMS)technology demonstrates immense potential in TCM analysis due to its high sensitivity,high resolution,high throughput,and high efficiency.However,its application in TCM research remains constrained by the lack of intelligent analytical methods and unified standardized databases.Therefore,this paper focuses on the integration of artificial intelligence(AI)and mass spectrometry,providing a systematic review of the applications and potential of AI-driven mass spectrometry analysis in structural elucidation,data resource integration,multi-omics mechanism studies,and chemical biology.Furthermore,this article emphasizes that by leveraging AI models to learn the complex mapping from chemical structures to biological functions,fragmentbased characterization has emerged as the bridge connecting chemical structures with biological activities.Molecular fragments themselves serve as the core“knowledge units”that carry bioactive information.Future research will focus on establishing highquality mass spectrometry databases for the complete chemical profiles of TCM and promoting the standardization and open sharing of mass spectrometry databases,thereby advancing the integration of AI and mass spectrometry in TCM analysis and providing new tools for TCM research. 展开更多
关键词 Artificial Intelligence Fragment-based representation Mass spectrometry Structural elucidation Traditional Chinese medicine
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Identifying purgative targets of sennoside A via in situ biotransformation of prodrug-based probes
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作者 Zhen Liu Xinyue Geng +6 位作者 Xinyue Liu Mengru Li Xiang Li Zhixin Zhang Gan Luo Ying Wang Xiaoyan Gao 《Journal of Pharmaceutical Analysis》 2025年第4期873-875,共3页
Prodrugs need to be converted to active drugs to exert their pharmacological activities.Identifying the direct targets of active drugs is essential to elucidate the pharmacological mechanisms of prodrugs,but remains c... Prodrugs need to be converted to active drugs to exert their pharmacological activities.Identifying the direct targets of active drugs is essential to elucidate the pharmacological mechanisms of prodrugs,but remains challenging,especially for active drugs with low stability. 展开更多
关键词 purgative targets active drugs pharmacological activities exert their pharmacological activitiesidentifying direct targets active drugs prodrug based probes situ biotransformation direct targets elucidate pharmacological mechanisms
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Advancing network pharmacology with artificial intelligence:the next paradigm in traditional Chinese medicine 被引量:3
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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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Diterpene chemical space of Aeollanthus buchnerianus Briq.aerial part
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作者 Gabin T.M.Bitchagno Nathan Reynolds Monique S.J.Simmonds 《Natural Products and Bioprospecting》 2025年第1期21-34,共14页
The Plectranthinae clade,which includes genera such as Plectranthus,Ocimum,and Aeollanthus,is well known for its diverse array of diterpenoids.While numerous studies have deepened the understanding of diterpene divers... The Plectranthinae clade,which includes genera such as Plectranthus,Ocimum,and Aeollanthus,is well known for its diverse array of diterpenoids.While numerous studies have deepened the understanding of diterpene diversity across the clade,Aeollanthus species remain underexplored,with only two studies focusing on their diterpene profiles.The NMR-based chemical profiling of the EtOAc leaf extract of the rocky and succulent species Aeollanthus buchnerianus Briq.reveals a range of diterpenes with isopimarane and abietane skeletons including several previously unreported analogues.Interestingly,the isolated compounds provided insights into the breakdown patterns of both diterpene classes by examining the product ions in their MS2 spectra.These data offer valuable information for evaluating the taxonomic position of this species in relation to other species within the clade. 展开更多
关键词 METABOLOMIC Aeollanthus buchnerianus Isopimarane ABIETANE Structure elucidation Lamiaceae
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Hymoins A–C,three unusual polycyclic polyprenylated acylphloroglucinols with lipid-lowering activity from Hypericum monogynum
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作者 Chunmao Yuan Yanrong Zeng +5 位作者 Lei Huang Yu Mou Jun Jin Ping Yi Yanmei Li Xiaojiang Hao 《Chinese Chemical Letters》 2025年第3期411-414,共4页
Hymoins A–C(1–3),three unusual polycyclic polyprenylated acylphloroglucinols(PPAPs)were isolated from the flowers of Hypericum monogynum.Hymoin A features the first intriguing 6/5/5/5/7 pentacyclic caged PPAP.Hymoin... Hymoins A–C(1–3),three unusual polycyclic polyprenylated acylphloroglucinols(PPAPs)were isolated from the flowers of Hypericum monogynum.Hymoin A features the first intriguing 6/5/5/5/7 pentacyclic caged PPAP.Hymoin B is characterized by an unprecedented rearranged 5/6/8 tricyclic ring system,while hymoin C represents the first rearranged PPAP with a fantastic spirocyclic 5/6/7 ring system.Their structures were established by extensive spectroscopic analysis,X-ray crystallography,and computational methods.The plausible biosynthetic routes for the compounds were also proposed.In oleic acid(OA)-induced HepG2 cells,all compounds exhibited significant lipid-lowering activity at the concentrations of 2–8μmol/L.Further mechanistic study implied that compound 1 exhibited excellent lipid-lowering activity in OA-induced HepG2 cells through inhibiting the proteins of free fatty acids synthesis and improving lipidolysis. 展开更多
关键词 Hypericum monogynum Polycyclic polyprenylated ACYLPHLOROGLUCINOLS Structure elucidation Lipid-lowering activity Mechanistic study
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(±)-Talapyrones A−F:six pairs of dimeric polyketide enantiomers with unusual 6/6/6 and 6/6/6/5 ring systems from Talaromyces adpressus
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作者 Meijia Zheng Xinyi Zhao +9 位作者 Chenxi Zhou Hong Liao Qin Li Yuling Lu Bingbing Dai Weiguang Sun Ying Ye Chunmei Chen Yonghui Zhang Hucheng Zhu 《Chinese Journal of Natural Medicines》 2025年第8期932-937,共6页
(±)-Talapyrones A−F(1−6),six pairs of dimeric polyketide enantiomers featuring unusual 6/6/6 and 6/6/6/5 ring systems,were isolated from the fungus Talaromyces adpressus.Their structures were determined by spectr... (±)-Talapyrones A−F(1−6),six pairs of dimeric polyketide enantiomers featuring unusual 6/6/6 and 6/6/6/5 ring systems,were isolated from the fungus Talaromyces adpressus.Their structures were determined by spectroscopic analysis and HR-ESI-MS data,and their absolute configurations were elucidated using a modified Mosher’s method and electronic circular dichroism(ECD)calculations.(±)-Talapyrones A−F(1−6)possess a 6/6/6 tricyclic skeleton,presumably formed through a Michael addition reaction between one molecule ofα-pyrone derivative and one molecule of C8 poly-β-keto chain.In addition,compounds 2/3 and 4/5 are two pairs of C-18 epimers,respectively.Putative biosynthetic pathways of 1−6 were discussed. 展开更多
关键词 POLYKETIDES Talaromyces adpressus ENANTIOMERS Structure elucidation Biosynthetic pathways
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Emestrin-type epipolythiodioxopiperazines from Aspergillus nidulans with cytotoxic activities by regulating PI3K/AKT and mitochondrial apoptotic pathways
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作者 Pengkun Li Qin Li +7 位作者 Aimin Fu Yang Xiao Chunmei Chen Hucheng Zhu Changxing Qi Wei Wei Yuan Zhou Yonghui Zhang 《Natural Products and Bioprospecting》 2025年第2期39-50,共12页
Five novel emestrin-type epipolythiodioxopiperazines(ETPs),prenylemestrins C-G(1-5),along with two known ETPs,prenylemestrin A(6)and prenylemestrin B(7),were obtained from Aspergillus nidulans.Their structures were ch... Five novel emestrin-type epipolythiodioxopiperazines(ETPs),prenylemestrins C-G(1-5),along with two known ETPs,prenylemestrin A(6)and prenylemestrin B(7),were obtained from Aspergillus nidulans.Their structures were characterized by spectroscopic data,X-ray crystallographic data,ECD comparisons and calculations.Prenylemestrins C-G(1-5)represent a rare class of ETPs,characterized by a 2,5-dithia-7,9-diazabicyclo[4.2.2]decane-8,10-dione core involving a hemiterpene moiety.Notably,compound 6 exhibited moderate cytotoxicity,inducing G2/M cell cycle arrest and apoptosis of L1210 cells by regulating the PI3K/AKT signaling pathway and mitochondrial apoptotic mechanisms. 展开更多
关键词 Aspergillus nidulans Epipolythiodioxopiperazines Thioethanothio bridge Structural elucidation CYTOTOXICITY
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Ten new lignans with anti-inflammatory activities from the leaves of Illicium dunnianum
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作者 Ting Li Xiaoqing He +7 位作者 Dabo Pan Xiaochun Zeng Siying Zeng Zhenzhong Wang Xinsheng Yao Wei Xiao Haibo Li Yang Yu 《Chinese Journal of Natural Medicines》 2025年第8期990-996,共7页
The anti-inflammatory phytochemical investigation of the leaves of Illicium dunnianum(I.dunnianum)resulted in the isolation of five pairs of new lignans(1–5),and 7 known analogs(6–12).The separation of enantiomer mi... The anti-inflammatory phytochemical investigation of the leaves of Illicium dunnianum(I.dunnianum)resulted in the isolation of five pairs of new lignans(1–5),and 7 known analogs(6–12).The separation of enantiomer mixtures 1–5 to 1a/1b–5a/5b was achieved using a chiral column with acetonitrile−water mixtures as eluents.The planar structures of 1–2 were previously undescribed,and the chiral separation and absolute configurations of 3–5 were reported for the first time.Their structures were determined through comprehensive spectroscopic data analysis[nuclear magnetic resonance(NMR),high-resolution electrospray ionization mass(HR-ESI-MS),infrared(IR),and ultraviolet(UV)]and quantum chemistry calculations(ECD).The new isolates were evaluated by measuring their inhibitory effect on NO in lipopolysaccharide(LPS)-stimulated BV-2 cells.Compounds 1a,3a,3b,and 5a demonstrated partial inhibition of NO production in a concentration-dependent manner.Western blot and real-time polymerase chain reaction(PCR)assays revealed that 1a down-regulated the messenger ribonucleic acid(mRNA)levels of tumor necrosis factorα(TNF-α),interleukin-6(IL-6),COX-2,and iNOS and the protein expressions of COX-2 and iNOS.This research provides guidance and evidence for the further development and utilization of I.dunnianum. 展开更多
关键词 Illicium dunnianum Lignan Structural elucidation Anti-inflammatory activity
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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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Bioactivity-guided discovery of antiviral templichalasins A-C from the endophytic fungus Aspergillus templicola
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作者 Teng Cai Jingzu Sun +7 位作者 Wenxuan Chen Qiang He Baosong Chen Yulong He Peng Zhang Yanhong Wei Hongwei Liu Xiaofeng Cai 《Chinese Journal of Natural Medicines》 2025年第6期754-761,共8页
The bioactivity-guided isolation of potentially active natural products has been widely utilized in pharmaceutical discovery.In this study,by screening fungal extracts against coxsackievirus B3(CVB3),three new aspocha... The bioactivity-guided isolation of potentially active natural products has been widely utilized in pharmaceutical discovery.In this study,by screening fungal extracts against coxsackievirus B3(CVB3),three new aspochalasins,templichalasins A-C(1-3),along with six known aspochalasins(4-9)were isolated from an active extract derived from the endophytic fungus Aspergillus templicola LHWf045.Compound 1 features a unique 5/6/5/7/5 pentacyclic ring system,while compounds 2 and 3 possess unusual 5/6/6/7 tetracyclic skeletons.Their structures were characterized through extensive spectroscopic analyses,electronic circular dichroism(ECD)calculations,and single-crystal X-ray diffraction analysis.Additionally,we demonstrated that compound 4 can be readily converted into compounds 1-3 under mild acidic conditions and proposed a plausible mechanism for this conversion.Bioactivity evaluation of compounds 1-9 against CVB3 revealed the inhibitory effects of all compounds against the virus.Notably,compound 9 exhibited superior antiviral activity,surpassing the commercial drug ribavirin in selectivity index(SI)value. 展开更多
关键词 Aspergillus templicola Aspochalasins Structural elucidation Antiviral activity
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MYCN-Mediated Transcriptional Activation of IDH2 Enhances Proliferation,Migration,and Invasion in Cervical Squamous Cell Carcinoma through the HIF1-αPathway
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作者 Xiaojuan Liu Hui Ma +3 位作者 Xiaoyan Li Chunxing Ma Lisha Shu Huiying Zhang 《Biomedical and Environmental Sciences》 2025年第8期1003-1008,共6页
Cervical cancer is a major malignancy that poses a significant threat to women's health[1].In 2020,an estimated 604,000 new cases and 342,000 deaths were reported globally[2].The most common pathological subtype i... Cervical cancer is a major malignancy that poses a significant threat to women's health[1].In 2020,an estimated 604,000 new cases and 342,000 deaths were reported globally[2].The most common pathological subtype is squamous cell carcinoma[3,4].However,treatment options for advanced cervical squamous cell carcinoma(CSCC)are limited.Surgery is often not feasible at this stage,resulting in poor prognosis[5,6].Therefore,identifying novel molecular markers and elucidating the mechanisms that drive CSCC growth and metastasis are crucial for improving treatment outcomes. 展开更多
关键词 IDH MYCN HIF elucidating mechanisms squamous cell carcinoma howevertreatment novel molecular markers cervical cancer PROLIFERATION
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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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New acylphloroglucinol-sesquiterpenoid adducts with antiviral activities from Dryopteris atrata
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作者 Jihui Zhang Jinghao Wang +8 位作者 Wei Tang Xi Shen Jinlin Chen Huilin Ou Qianyi Situ Yaolan Li Guocai Wang Yubo Zhang Nenghua Chen 《Chinese Journal of Natural Medicines》 2025年第3期377-384,共8页
Seven novel acylphloroglucinol-sesquiterpenoid adducts,designated as dryatraols J-P(1-7),were isolated from the rhizomes of Dryopteris atrata(Wall.ex Kunze)Ching.The structures,including absolute configurations,were e... Seven novel acylphloroglucinol-sesquiterpenoid adducts,designated as dryatraols J-P(1-7),were isolated from the rhizomes of Dryopteris atrata(Wall.ex Kunze)Ching.The structures,including absolute configurations,were elucidated using comprehensive spectroscopic data,calculated 13C Nuclear Magnetic Resonance-Diastereotopic Probability Assignment Plus(13C NMR-DP4+)probability analysis,and ECD calculations.These structures represent a rare subclass of carbon skeleton of acylphloroglucinol-sesquiterpenoid adducts with a furan ring connecting the acylphloroglucinol and sesquiterpenoid moieties.Notably,compounds 1-6 are the first reported examples of acylphloroglucinol-sesquiterpenoid adducts with dimeric acylphloroglucinol incorporated into the aristolane-or rulepidanol-type sesquiterpene,while compound 7 features a hydroxylated monomeric acylphloroglucinol motif.A preliminary evaluation of their antiviral activities revealed that compounds 1-6 exhibited more potent activities against respiratory syncytial virus(RSV)with IC50 values ranging from 0.75 to 3.12μmol·L^(-1) compared to the positive control(ribavirin). 展开更多
关键词 Dryopteris atrata Acylphloroglucinol-sesquiterpenoid adducts Structural elucidation Antiviral activities
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Ophiobolin-type sesterterpenoids with unprecedented chemical architectures from Bipolaris oryzae and their inflammatory activity
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作者 Meijia Zheng Yingjie Liu +6 位作者 Chunmei Chen Qin Li Xinran Zhang Xiaotian Zhang Weiguang Sun Yonghui Zhang Hucheng Zhu 《Chinese Chemical Letters》 2025年第12期307-312,共6页
Bipolarpenoids A–J(1–10),ten undescribed ophiobolin-derived sesterterpenoids,were identified from the fungus Bipolaris oryzae.Their structures were elucidated by high resolution electrospray ionization mass spectrom... Bipolarpenoids A–J(1–10),ten undescribed ophiobolin-derived sesterterpenoids,were identified from the fungus Bipolaris oryzae.Their structures were elucidated by high resolution electrospray ionization mass spectrometry(HRESIMS),spectroscopic analyses,quantum chemical ^(13)C nuclear magnetic resonance(NMR),electronic circular dichroism(ECD)calculations,and single-crystal X-ray diffraction analyses.Notably,compounds 1 and 2 were uniquely characterized by a multicyclic caged pentacyclo[8.4.0.0^(1,5).0^(4,9).0^(7,11)]tetradecane-bridged system;compounds 4–6 featured unprecedented5/8/5/6 and 5/8/5/5 fused cores,respectively;compound 7 represented the first example of 3,4-secoophiobolin-alkaloid hybrid with a modified 5/6/8/5/5 fused carbon skeleton.Compound 9 showed potential anti-inflammatory effect in RAW264.7 macrophages and ulcerative colitis mice. 展开更多
关键词 Bipolaris oryzae Ophiobolin-derived sesterterpenoids Structure elucidation Anti-inflammatory activities Putative biosynthetic pathways
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Physiologically relevant coculture model for oral microbial-host interactions
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作者 Zeyang Pang Nicole M.Cady +3 位作者 Lujia Cen Thomas M.Schmidt Xuesong He Jiahe Li 《International Journal of Oral Science》 2025年第4期517-528,共12页
Understanding microbial-host interactions in the oral cavity is essential for elucidating oral disease pathogenesis and its systemic implications.In vitro bacteria-host cell coculture models have enabled fundamental s... Understanding microbial-host interactions in the oral cavity is essential for elucidating oral disease pathogenesis and its systemic implications.In vitro bacteria-host cell coculture models have enabled fundamental studies to characterize bacterial infection and host responses in a reductionist yet reproducible manner.However,existing in vitro coculture models fail to establish conditions that are suitable for the growth of both mammalian cells and anaerobes,thereby hindering a comprehensive understanding of their interactions.Here,we present an asymmetric gas coculture system that simulates the oral microenvironment by maintaining distinct normoxic and anaerobic conditions for gingival epithelial cells and anaerobic bacteria,respectively.Using a key oral pathobiont,Fusobacterium nucleatum,as the primary test bed,we demonstrate that the system preserves bacterial viability and supports the integrity of telomerase-immortalized gingival keratinocytes.Compared to conventional models,this system enhanced bacterial invasion,elevated intracellular bacterial loads,and elicited more robust host pro-inflammatory responses,including increased secretion of CXCL10,IL-6,and IL-8.In addition,the model enabled precise evaluation of antibiotic efficacy against intracellular pathogens.Finally,we validate the ability of the asymmetric system to support the proliferation of a more oxygen-sensitive oral pathobiont,Porphyromonas gingivalis.These results underscore the utility of this coculture platform for studying oral microbial pathogenesis and screening therapeutics,offering a physiologically relevant approach to advance oral and systemic health research. 展开更多
关键词 elucidating oral disease pathogenesis oral microbial host interactions Fusobacterium nucleatum oral cavity coculture model mammalian cells vitro coculture models bacterial infection
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