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Isolation,Structural Assignment of Isoselagintamarlin A from Selaginella tamariscina and Its Biomimetic Synthesis

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Natural Products and Bioprospecting 2019年第1期9卷 69-74页

作者： Qin-Feng Zhu Li-Dong Shao xing-de wu Jiang-Xin Liu Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Isoselagintamarlin A(1),a selaginellin analogue featured a rare benzofuran unit,was isolated from Selaginella *** complete structural assignment was established through a combination of high-feld NMR technique and biomimetic ***,isoselagintamarlin A(1)was successfully synthesized via sequential oxidations and intramolecular cyclization.

关键词： Selaginella tamariscina Selaginellin Biomimetic synthesis Isoselagintamarlin A

Chemical constituents from the aerial parts of Musella lasiocarpa

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Natural Products and Bioprospecting 2011年第1期1卷 41-47页

作者： Liao-Bin DONG Juan HE xing-Yao LI xing-de wu Xu deNG Gang XU Li-Yan PENG Yu ZHAO Yan LI Xun GONG Qin-Shi ZHAO State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Graduate University of Chinese Academy of Sciences Beijing 100039China

Phytochemical investigation of the aerial parts of the monotypic plant,Musella lasiocarpa,led to the isolation of four rare bicyclic diarylheptanoids,musellarins B-E(2-5),two new phenylphenalenones,2-methoxy-9-(3′,4′-dihydroxyphenyl)-1H-phenalen-1-one(9),2-methoxy-9-(3′-methoxy-4′-hydroxyphenyl)-1H-phenalen-1-one(10),a new acenaphtylene derivative,trans-(1S,2S)-3-(4′-methoxyphenyl)-acenaphthene-1,2-diol(13),and two new sucrose esters,1,2′,3′,4′,6′-O-pentaacetyl-3-O-trans-p-coumaroylsucrose(16),1,2′,3′,4′,6′-O-pentaacetyl-3-O-cis-p-coumaroylsucrose(17),together with nine known *** addition,(4E,6E)-1-(3′,4′-dihydroxyphenyl)-7-(4′′-hydroxyphenyl)-hepta-4,6-dien-3-one(15)was isolated for the first time from a natural *** structures of new compounds were elucidated by analysis of their spectroscopic *** 2,6,8-10,12,and 14 were cytotoxic toward several of the human tumor cell lines(HL-60,SMMC-7721,A-549,MCF-7,and SW480).Of these,the new compound 9 was the most potent one,with IC50 values of 5.8,10.3,6.3,3.3,and 2.3μM,respectively.

关键词： monotypic diarylheptanoid phenylphenalenone acenaphtylene sucrose ester Musella lasiocarpa

Lycodine-Type Lycopodium Alkaloids from the Whole Plants of Huperzia serrata

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Natural Products and Bioprospecting 2017年第5期7卷 405-411页

作者： Yu-Chen Liu Zhi-Jun Zhang Jia Su Li-Yan Peng Lu-Tai Pan xing-de wu Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China University of Chinese Academy of Sciences Beijing 100039People’s Republic of China Guiyang College of Traditional Chinese Medicine GuiyangPeople’s Republic of China

t Three new lycodine-type Lycopodium alkaloids,namely 1-methyllycodine(1),8a-hydroxy-15,16-dehydro-desN-methyl-a-obscurine(2),N-methyl-16-hydroxyhuperzine B(3),and one new natural lycodine-type Lycopodium alkaloid,N-methylhuperzine A(4),along with 11 known analogues(5–15),were isolated from the whole plants of club moss Huperzia *** structures of 1–4 were elucidated on the basis of NMR spectroscopic and mass spectrometry *** them,compound 1 was the first lycodine-type alkaloid possessing a methyl group at *** addition,the structure of 5 was confirmed by the single-crystal X-ray crystallography data and its^(13)C NMR was reported for the first time in current *** 1–5 were tested their BACE1 inhibitory activity.

关键词： Lycopodium alkaloids Lycodine-type Huperzia serrata BACE1 inhibitory activity

(±)-Evodiakine,A Pair of Rearranged Rutaecarpine-Type Alkaloids From Evodia rutaecarpa

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Natural Products and Bioprospecting 2016年第6期6卷 291-296页

作者： Yan-Hong Li Yu Zhang Li-Yan Peng Xiao-Nian Li Qin-Shi Zhao Rong-Tao Li xing-de wu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China

(±)-Evodiakine(1a and 1b),a pair of rearranged rutaecarpine-type alkaloids with an unprecedented 6/5/5/7/6 ring system,were isolated from the nearly ripe fruits of Evodia *** of the enantiomers have been achieved by chiral HPLC *** structures of(±)-evodiakine were unambiguously elucidated by 1D and 2D NMR spectra,mass spectrometry,and single-crystal X-ray *** absolute configurations were determined by comparison of experimental and calculated electronic circular dichroism spectra.A hypothetical biogenetic pathway for(±)-evodiakine was also *** 1a,1b,and the racemate(1)were tested for their cytotoxic and anti-inflammatory activities.

关键词： Evodia rutaecarpa (±)-Evodiakine Rutaecarpine-type alkaloids

Lyconadins G and H,Two Rare Lyconadin-Type Lycopodium Alkaloids from Lycopodium complanatum

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Natural Products and Bioprospecting 2016年第6期6卷 279-284页

作者： Jin-Tang Cheng Zhi-Jun Zhang Xiao-Nian Li Li-Yan Peng Huai-Rong Luo xing-de wu Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700People’s Republic of China

Two rare lyconadin-type Lycopodium alkaloids,lyconadins G(1)and H(2),together with four known ones(3–6),were isolated from Lycopodium *** structures were determined on the basis of their spectroscopic analyses,and the absolute configuration of 1 was established by an X-ray crystallographic *** is the first time to establish the absolute configuration of lyconadin-type Lycopodium alkaloid by an X-ray diffraction *** addition,these findings may provide more information for the biosynthesis of lyconadins.

关键词： Lycopodium alkaloids Lycopodium complanatum Lyconadin

Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue

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Computers, Materials & Continua 2025年第1期82卷 751-775页

作者： Yuewei wu Ruiling Fu Tongtong xing Fulian Yin College of Information and Communication Engineering Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large *** imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation *** to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction *** can be categorized such as by features and classes,but most studies consider only class *** this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss *** propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature *** network incorporates an attention mechanism and uses multiple sub-networks to classify and learn *** better results,the network can learn the weights of sub-networks and assign higher weights to important *** propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision *** on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods.

关键词： Imbalanced data deep learning e-commerce recommendation loss function big data analysis

Lycopodine-Type Alkaloids from Lycopodium japonicum

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Natural Products and Bioprospecting 2014年第4期4卷 213-219页

作者： Juan He xing-de wu Fei Liu Yu-Cheng Liu Li-Yan Peng Yu Zhao Xiao Cheng Huai-Rong Luo Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

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 *** Murray(Lycopodiaceae).Their structures were elucidated by extensive spectroscopic methods as well as X-ray *** 1–4 were evaluated for their acetylcholine esterase inhibitory activity.

关键词： Lycopodium japonicum Lycopodine-type alkaloids 4a-Hydroxyanhydrolycodoline 4a,6a-Dihydroxyanhydrolycodoline 6-epi-8b-Acetoxylycoclavine Lycoposerramine G nitrate

New Lycopodium alkaloids from Lycopodium obscurum

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Natural Products and Bioprospecting 2013年第2期3卷 52-55页

作者： Xue-Yuan ZHANG Liao-Bin DONG Fei LIU xing-de wu Juan HE Li-Yan PENG Huai-Rong LUO Qin-Shi ZHAO State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Three new Lycopodium alkaloids,obscurumines C-E(1-3),along with nine known compounds,were isolated from the club moss Lycopodium obscurum *** of the new compounds were determined on the basis of their spectroscopic analysis and the relative configurations of 1 were established by X-ray crystallographic *** the new isolates were tested for the acetylcholinesterase(AChE)inhibitory activity.

关键词： obscurumines Lydopodium alkaloids Lycopodium obscurum acetylcholinesterase(AChE)inhibitory activity

Carinatines A and B,Lycopodium Alkaloids from Phlegmariurus carinatus

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Natural Products and Bioprospecting 2014年第4期4卷 221-225页

作者： Fei Liu Yu-Cheng Liu Wei-Wei Jiang Juan He xing-de wu Li-Yan Peng Jia Su Xiao Cheng Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201People’s Republic of China University of the Chinese Academy of Sciences Beijing 100049People’s Republic of China

Carinatine A(1),a C16N2-type Lycopodium alkaloid possessing a 5/6/6/6 ring system formed by a new C-4/C-12 bond,and carinatine B(2),the first derivative of lycojaponicumin C,along 16 known compounds,were isolated from the whole plant of Phlegmariurus *** structures were elucidated based on the spectroscopic *** two new isolates were no inhibitory activity for the acetylcholinesterase(AChE).

关键词： Lycopodium alkaloid Phlegmariurus carinatus Carinatines A and B Acetylcholinesterase(AChE)inhibitory activity