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A new butenolide derivative from the deep-sea fungus Aspergillus terreus SCSIO FZQ028

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A new butenolide derivative from the deep-sea fungus Aspergi...

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

中国化学会第十二届全国天然有机化学学术会议

作者： Qi Zeng wei-mao zhong Yao Xiang Xia-Yu Chen Fa-Zuo Wang CAS Key Laboratory of Tropical Marine Bioresource and Ecology South China Sea Institute of OceanologyChinese Academy of Sciences University of Chinese Academy of Science

The fungus Aspergillus terreus is ubiquitous in the marine benthos and terrestrial plants,which has been reported to be rich in butenolides,alkaloids,terpenoids,and *** compounds have attracted widespread attention for their prominent bioactivities,such as antimicrobial,antioxidant,cytotoxicity,and α-glucosidase inhibitory *** our continuing search for bioactive metabolites from deep-sea sediments of South China Sea fungus Aspergillus terreus SCSIO FZQ028,a new butanolide derivative asperteretal F(1) and a very recently reported related compound 2 containing an unusual 2-benzyl-3-phenyl substituted lactone core,together with seven known compounds(3-9) were isolated and *** chemical structures were established on the basis of 1 D and 2 D NMR,HR-ESI-MS spectroscopic data *** the compounds were evaluated for antioxidative activities by DPPH methods,cytotoxic activities against two tumor cell lines(SF-268 and HepG-2),and antimicrobial *** 2-4 and 7 showed significant activities against DPPH(IC=5.89-10.07μg/mL).Compound 2 showed good antimicrobial activity against all four test *** compounds showed potent cytotoxic activities.

关键词： Aspergillus terreus butenolides Structural elucidation bioactivities

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-wei Yao Xing-zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Secondary Metabolites from Marine-Derived Fungus Eurotium *** F452

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Secondary Metabolites from Marine-Derived Fungus Eurotium **...

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

中国化学会第十二届全国天然有机化学学术会议

作者： wei-mao zhong Qi Zeng Yao Xiang Xia-Yu Chen Fa-Zuo Wang Si Zhang CAS Key Laboratory of Tropical Marine Bio-resources and Ecology RNAM Center for Marine MicrobiologyGuangdong Key Laboratory of Marine Materia MedicaSouth China Sea Institute of OceanologyChinese Academy of Sciences University of Chinese Academy of Sciences

Marine-derived fungi have been proven to be a prolific source of structurally diverse and biologically active natural products,including polyketides,alkaloids,meroterpenoids,and cyclic *** compounds exhibit various biological activities such as antibacterial,antitumor,antiviral,and *** the course of our continuing investigation on marine fungi,a further chemical investigation was performed on Eurotium *** F452,a South China Sea sediment derived fungus found to be producing diketopiperazine alkaloids and *** chemical examination led to the isolation and characterization of compounds 1-7(Figure 1).Their structures were elucidated as eurotiumin F(1),2-(2,3-epoxy-1-heptenyl)-6-hydroxy-5-(3-methyl-2-butenyl)benzaldehyde(2),2-(2,3-epoxy-1,3-heptadienyl)-6-hydroxy-5-(3-methyl-2-butenyl)benzaldehyde(3),flavoglaucin(4),2-(E-3-heptneyl)-3,6-dihydroxy-5-(3-methyl-2-butenyl)-benzaldehyde(5),isotetrahydroauroglaucin(6),and dihydroauroglaucin(7) by comprehensive spectroscopic *** new compound 1 was evaluated for its cytotoxic activity against SF-268 and HepG2 cell lines with SRB method and didn’t showed activity(IC>100μM).

关键词： Marine fungi Secondary metabolites Cytotoxic activity

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Science China(Information Sciences) 2025年第1期68卷 145-158页

作者： wei JU Yiyang GU Zhengyang mao Ziyue QIAO Yifang QIN Xiao LUO Hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

关键词： graph representation learning graph neural networks graph contrastive learning graph augmentations graph pooling

Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie Duan Linjiao mao Xuhui Zeng Xi Luo Yuntao Zhang Yuqin Dong Jin zhong Zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du wei Huang Yufeng Xue Xiaokun Xu Guannan zhong Yuanyuan Shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

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公共图书馆应积极为建设学习型社区服务

科技情报开发与经济 2006年第16期16卷 44-46页

作者：毛为忠江山市图书馆浙江江山324100

论述了构建学习型社区的重要性,分析了学习型社区现状及存在的问题,就图书馆应如何积极参与学习型社区建设,更好地为读者服务展开了讨论。

关键词：学习型社区社区建设公共图书馆

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论知识经济时代公共图书馆员的素质教育

科技情报开发与经济 2007年第3期17卷 68-70页

作者：毛为忠江山市图书馆浙江江山324000

论述了知识经济时代对公共图书馆员综合素质的新要求,分析了图书馆业务队伍的现状及存在问题,并从5个方面提出了提高图书馆员综合素质的措施。

关键词：公共图书馆员素质教育知识经济

无创指标对乙型肝炎肝硬化患者食管静脉曲张程度的预测价值

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分子影像学杂志 2018年第2期41卷 233-236页

作者：韦仲毛华南方医科大学珠江医院消化内科广东广州510282

目的探讨瞬时弹性成像技术联合血清学指标、肝脏超声检查对食管静脉曲张程度的预测价值,并建立能够预测食管胃底静脉曲张程度的模型。方法按胃镜检查结果,将110例乙肝肝硬化失代偿期患者按食管胃底静脉曲张程度分为:无或轻度组,中或重... 详细信息

目的探讨瞬时弹性成像技术联合血清学指标、肝脏超声检查对食管静脉曲张程度的预测价值,并建立能够预测食管胃底静脉曲张程度的模型。方法按胃镜检查结果,将110例乙肝肝硬化失代偿期患者按食管胃底静脉曲张程度分为:无或轻度组,中或重度组。对肝脏硬度值、血小板计数、凝血时间、血清白蛋白水平、脾脏厚度、门静脉直径、肝脏直径进行单因素分析和logistic回归分析,筛选出可以有效预测食管静脉曲张及程度的无创指标,并在此基础上构建预测模型。应用受试者工作特征曲线分析方法评价模型的诊断价值。结果建立预测食管静脉曲张程度的回归方程:y=1.07×肝脏硬度值-0.057×血小板计数+0.783×凝血时间+1.876×门脉直径-0.06×脾脏厚度-40.248,ROC曲线下面积为0.979,诊断敏感性为98.7%,特异度为97.1%。结论瞬时弹性成像技术检测肝脏硬度值联合血小板计数、凝血时间、门静脉宽度、脾脏厚度等指标建立的无创预测模型预测食管静脉曲张准确、敏感,具有一定的临床应用价值。

关键词：肝硬化失代偿食管静脉曲张瞬时弹性成像技术无创诊断