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Chinese Journal of Structural Chemistry 2020年第7期39卷 1277-1282页

作者： WU Yia YE Qing-Mei QIN Shu-Qin jiang ren-wang Zhongshan Torch Polytechnic Zhongshan 528436China Department of Pharmacy Hainan General HospitalHaikou 570311China Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research Chinese Medicine Modernization and Innovative Drug Development of Chinese Ministry of EducationJinan UniversityGuangzhou 510632China

The title compound maistemonine(1)was isolated from the total alkaloid fraction of the 95%ethanol extract of the roots of Stemona japonica,followed by preparative HPLC and recrystallization from a mixture of n-hexane and ethyl *** crystal structure of 1,C23H29NO)6,was determined by single-crystal X-ray diffraction *** crystal belongs to orthorhombic system,space group P212121 with a=8.5698(6),b=14.0460(11),c=17.8815(17)?,V=2152.4(3)?3,Z=4,Mr=415.47,Dc=1.282 g/cm3,λ=0.71079?,μ=0.092 cm^–1,F(000)=888,S=0.995,R=0.0535 and wR=0.1067.A total of 5136 unique reflections were collected,of which 3523 were observed(Ⅰ>2σ(Ⅰ)).The absolute configuration of 1 could be assigned by referring to the conserved configuration of the methyl groups at C(2).Compound 1 shows mild cytotoxic activity against the prostate cancer cells LNCaP and PC3 with the IC50 values of 29.4±2.3 and 46.6±3.1 mM,*** is noteworthy that the natural maistemonine(1)is different from the synthetic compound which was a racemic with the triclinic space group *** lactone rings E from the natural and synthetic 1 are almost perpendicular to each other when overlapping the remaining parts of the molecules.

关键词： maistemonine isolation crystal structure cytotoxic comparison synthesis

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蟾蜍胆的化学成分及其生物合成研究进展

药学学报 2024年第6期59卷 1616-1626页

作者：阮丽君闫炳雄吴云秋姚彩云杨晓男宋志军江仁望广西壮族自治区药用植物园西南濒危药材资源开发国家工程研究中心广西南宁530023 暨南大学药学院生物活性分子和成药性评价全国重点实验室广东广州510632

蟾蜍是一种药用价值很高的经济动物,其耳后腺分泌物(蟾酥)、干燥皮(蟾皮)、胆汁(蟾胆)等部位皆可入药,是名贵的传统动物类中药材。目前,关于蟾酥和蟾皮的化学成分及药效活性已有较多报道,而对蟾胆化学成分的综述报道相对较少。本文综述... 详细信息

蟾蜍是一种药用价值很高的经济动物,其耳后腺分泌物(蟾酥)、干燥皮(蟾皮)、胆汁(蟾胆)等部位皆可入药,是名贵的传统动物类中药材。目前,关于蟾酥和蟾皮的化学成分及药效活性已有较多报道,而对蟾胆化学成分的综述报道相对较少。本文综述了蟾蜍属(Bufo)胆汁的化学成分,特别关注了胆甾烷类和蟾毒内酯类成分,并报道了这些成分的生物合成途径及药理活性研究进展。综述发现蟾胆存在一类特异的不饱和Δ22或Δ23-C27/C28胆甾酸,这类成分可能是蟾毒内酯C-17位α-吡喃酮形成的重要中间体。此外,还发现蟾胆中存在丰富的3α-OH构型蟾毒内酯,与以往从蟾酥或蟾皮分离的3β-OH构型不一致,这类成分的低毒性可能与蟾蜍的自我防御或生理调节相关。本综述为蟾胆资源的开发和利用提供科学依据,对药物先导化合物的发现、蟾毒内酯生物合成途径的解析和蟾蜍生理学研究提供有用借鉴。

关键词：蟾蜍属蟾胆胆甾烷蟾毒内酯生物合成

Staring-imaging satellite pointing estimation based on sequential ISAR images

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Chinese Journal of Aeronautics 2024年第8期37卷 261-276页

作者： Canyu wang Libing jiang Weijun ZHONG Xiaoyuan ren Zhuang wang National Key Laboratory of Automatic Target Recognition National University of Defense TechnologyChangsha 410073China Xi’an Satellite Control Center Xi’an 710600China

Pointing estimation for spacecraft using Inverse Synthetic Aperture Radar(ISAR)images plays a significant role in space situational awareness and ***,feature extraction and cross-range scaling of ISAR images create bottlenecks that limit performances of current estimation ***,the emergence of staring imaging satellites,characterized by complex kinematic behaviors,presents a novel challenge to this *** address these issues,this article proposes a pointing estimation method based on Convolutional Neural Networks(CNNs)and a numerical optimization algorithm.A satellite’s main axis,which is extracted from ISAR images by a proposed Semantic Axis Region Regression Net(SARRN),is chosen for investigation in this article due to its unique ***,considering the kinematic characteristic of the staring satellite,an ISAR imaging model is established to bridge the target pointing and the extracted *** on the imaging model,pointing estimation and cross-range scaling can be described as a maximum likelihood estimation problem,and an iterative optimization algorithm modified by using the strategy of random sampling-consistency check and weighted least squares is proposed to solve this ***,the pointing of targets and the cross-range scaling factors of ISAR images are *** experiments based on actual satellite orbital parameters verify the effectiveness of the proposed *** work can improve the performance of satellite reconnaissance warning,while accurate cross-range scaling can provide a basis for subsequent data processes such as 3D reconstruction and attitude estimation.

关键词： Staring-imaging Agile satellite Inverse Synthetic Aperture Radar(ISAR) Pointing estimation Cross-range scaling

Absolute configuration of podophyllotoxone and its inhibitory activity against human prostate cancer cells

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Chinese Journal of Natural Medicines 2015年第1期13卷 59-64页

作者： LI Juan FENG Juan LUO Cheng Herman Ho-Yung Sung jiang ren-wang Guangxi Key Laboratory of Functional Phytochemicals Research and Utilization Guangxi Institute of Botany Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research College of Pharmacy Jinan University State Key Laboratory of New Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Department of Chemistry The Hong Kong University of Science and Technology

Podophyllotoxone(1) was isolated from the roots of Dysosma versipellis. The structure was determined by spectroscopic analysis in combination with single-crystal X-ray analysis. The absolute configuration of compound 1 was assigned based on the Flack parameter. It showed significant inhibitory activities against human prostate cancer cells PC3 and DU145 with IC50 values being 14.7 and 20.6 μmol·L-1, respectively. It also arrested the cells at G2/M phase. Tubulin polymerization assay showed that it inhibited the tubulin polymerization in a dose-dependent manner, and molecular docking analysis revealed a different binding mode with tubulin as compared with those known tubulin inhibitors.

关键词： Podophyllotoxone Absolute configuration Prostate cancer Tubulin Molecular docking

Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China

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Chinese Geographical Science 2024年第5期34卷 791-809页

作者： DENG Wei jiang Zhenyuan ZHANG Shaoyao ren Ping ZHANG Hao wang Zhanyun The Faculty Geography Resources Science Sichuan Normal UniversityChengdu 610101China Sustainable Development Research Center of Resources and Environment in Western Sichuan Sichuan Normal UniversityChengdu 610101China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial *** a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential *** promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ *** proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R *** results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2)In 1990-2020,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in *** main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are *** study emphasizes the importance of elastic planning and precise governance within the U-

关键词： transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu,China

Development of functional dye with redshifted absorption based on Knoevenagel condensation at 1-site in phenyl[b]-fused BODIPY

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Chinese Chemical Letters 2024年第6期35卷 349-352页

作者： Tianze wang Junyi ren Dongxiang Zhang Huan wang Jianjun Du Xin-Dong jiang Guiling wang Liaoning&Shenyang Key Laboratory of Functional Dye and Pigment Shenyang University of Chemical TechnologyShenyang 110142China Department of Cell Biology China Medical UniversityShenyang 110122China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

Integrating ring-fused modification withπ-conjugated extension is an effective approach for designing,synthesizing,and application for novel borondipyrromethene(BODIPY)*** this work,based on phenyl[b]-fused BODIPY,we made reasonable modification of the methyl group at 1-site to generate dye *** possessed near-infrared region(NIR)absorption and emission properties,and the intramolecular charge transfer(ICT)resulted in low ***,heat energy is evidently released in the presence of light,which can be exploited for intracellular photothermal therapy via the cell apoptosis process,reducing the inflammatory side-effects induced by *** research provides a crucial foundation for the novel molecule via BODIPY multi-directional alteration and its potential application in anti-tumor phototherapy.

关键词： NIR dyes [b]-Fused BODIPY Knoevenagel condensation Photothermal therapy Cell apoptosis

A novel method for calculating broadband electrical performance of high-speed aircraft radome under thermo-mechanical-electrical coupling

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Chinese Journal of Aeronautics 2024年第9期37卷 463-474页

作者： Jianmin JI Jianhua ren Xunya jiang Wei wang Huilong YU Kai YIN Bo CHEN Beijing Institute of Remote Sensing Equipment Beijing 100854China Shanghai Dong Jun Information and Technology Co.Ltd Shanghai 200050China

The electrical performance of radomes on high-speed aircraft can be influenced by the thermal and mechanical loads produced during high-speed flight,which can affect the detection dis-tance and accuracy of the guidance *** paper presents a new method that uses the Finite Difference Time Domain(FDTD)method to calculate the electrical performance of radomes under Thermo-Mechanical-Electrical(TME)*** method can accurately characterize the effects of material dielectric temperature drift and structural deformation on the electrical performance of the radome under flight conditions,enabling high-precision full-wave calculations of the broadband electrical performance of the *** method initiates by utilizing a Finite Element Grid Model(FE-GM)of the radome to sequentially acquire the radome's response temperature field and structural deformation field through thermal and mechanical ***,spatial mapping techniques are developed to accurately incorporate the dielectric temperature drift and structural deformation of the radome into its Yee grid Electromagnetic(EM)simulation model.A verification case was designed to test the proposed method,and the results confirmed its high computational ***,the effectiveness and necessity of the method were further demonstrated by analyzing the electrical performance of a fused silica ceramic radome used on a high-speed aircraft.

关键词： High-speed aircraft Radomes Thermo-Mechanical-Electrical(TME)coupling Finite Difference Time Domain(FDTD)method Spatial mapping

Highly active organocatalyst from a trivalent phosphazenium salt for ring-opening copolymerization of epoxides and cyclic anhydrides enhanced by hydrogen bonding interactions

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Science China Chemistry 2024年第9期67卷 3111-3120页

作者： Chunhuan jiang Junqi wang Xiaoyu Liu Xiaoxia You Ronglin Zhong Chuanli ren Zhibo Li Key Laboratory of Biobased Polymer Materials Shandong Provincial Education DepartmentCollege of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130012China

It is highly desirable to develop simple organocatalysts for the controlled ring-opening alternating copolymerization(ROAC)of epoxides and cyclic anhydrides,leading to high molecular weight ***,a phosphazenium salt,namely tri[tris(dimethylamino)phosphoranylidenamino]phosphonium chloride(P_(4)^(+)Cl^(-)),is developed as a catalyst for the ROAC of epoxides and cyclic ***,the combination of P_(4)^(+)Cl^(-)with a protonic initiator,such as 1,4-benzenedimethanol(BDM)exhibited high efficiency in the copolymerization of propylene oxide(PO)and phthalic anhydride(PA).This led to the production of polyester with an exceptional high molecular weight(M_n)of up to 126 k Da,which represented a rare example of poly(PO-alt-PA)with Mnsurpassing 100 k *** that the core P atom is trivalent status and the tris[tris(dimethylamino)]phosphoranyl group will share one proton in the P_(4)^(+)Cl^(-)*** combined with protonic species,the P_(4)^(+)Cl^(-)will not only serve as a proton acceptor but also as a hydrogen bonding donor for the cyclic ***,it was assumed that the P_(4)^(+)plus proton served dual role in mimic of base/urea pair to effectively catalyze ROAC,which was supported by density functional theory(DFT)calculations.

关键词： ring-opening copolymerization organocatalyst epoxides cyclic anhydrides phosphazenium salt

Influence of erbium addition on microstructure and performances of AlSi10Mg alloy prepared by selective laser melting

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Journal of Rare Earths 2024年第10期42卷 1988-1994页

作者： Bin Chen Fuzhu wang Shiming ren Peng Xia Zhipeng wang Jianfei Hao Zhiping Chen Runxia Li Hongxiang jiang Research Institute of Interdisciplinary Science & School of Materials Science and Engineering Dongguan University of Technology College of Materials Science and Engineering Shenzhen University Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The effect of rare earth addition on the microstructure and mechanical performances of as-cast and wrought Al alloys has been attracting increasing attention *** earth addition has great potential in modifying the structure and improving the properties of ***,there are currently few reports about the effect of rare earth addition on the microstructure and performances of Al alloys prepared via selective laser ***,AlSi10Mg alloys were manufactured using selective laser melting,and the effect of Er addition was *** results indicate that Er addition leads toα-Al refinement and modifies the minority Si *** formation of the Al3Er phase induced by Er addition enhances the stren gth of the *** of the Si phase also increases *** strategy can help improve the mechanical performance of alum inum alloys prepared via selective laser melting.

关键词： Aluminum alloy Er Microstructure Rare earths Selective laser melting Tensile performance

Dicamba and Sugar Effects on Callus Induction and Plant Regeneration from Mature Embryo Culture of Wheat

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Agricultural Sciences in China 2010年第1期9卷 31-37页

作者： ren jiang-ping,wang Xin-guo and YIN Jun National Engineering Research Center for Wheat/Henan Agricultural University,Zhengzhou 450002,P.R.China National Engineering Research Center for Wheat/Henan Agricultural University Zhengzhou 450002 P.R. China

To establish a highly efficient plant regeneration system for wheat genetic transformation, the effects of three different concentrations of dicamba and two different sugar types on callus induction and plant regeneration from mature embryo cultures were evaluated. Callus induction and plant regeneration were obtained from mature embryos of two commercial cultivars Zhoumai 18 and Yumai 34 （Triticum aestivum L.） cultured on L3 basal medium. The results showed that the efficiency of mature embryo culture was significantly influenced by the genotypes, sugar types and dicamba concentrations. 4 mg L^-1 dicamba proved the best effective for inducing embryogenic callus and also gave the highest proportion of plants regenerated across the two cultivars. Substitution of maltose by sucrose significantly improved the plant regeneration efficiency in both cultivars. There was a significant interaction between genotype-by-sugar types, and sugar types-bydicamba concentrations. Overall, Zhoumai 18 gave the highest frequency of plant regeneration （82.65%） when dicamba concentration was 4.0 mg L^-1 and with sucrose in initial callus induction. These results will facilitate genetic transformation work with elite wheat.

关键词： wheat mature embryo tissue culture plant regeneration