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Structural characterization,in vivo toxicity and biological activity of two new pyro-type diterpenoid alkaloids derived from 3-acetylaconitine

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Journal of Integrative Medicine 2023年第3期21卷 302-314页

作者： yu-jie wang Yan wang Pei Tao School of Ethnic Medicine Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina

Objective:The transformations that occur in diterpenoid alkaloids during the process of sand frying for Chinese herbal medicine preparation have yet to be *** study investigated the structural changes that take place in 3-acetylaconitine during a simulation of heat-processing and evaluated the toxicity and biological activity of the pyrolysis ***:The diterpenoid alkaloid 3-acetylaconitine was heated at 180°C for 15 min to simulate the process of sand *** pyrolysis products were separated using column chromatography,and their structures were investigated using high-resolution electrospray ionization mass spectroscopy and nuclear magnetic resonance ***,in vivo cardiotoxicity and acute toxicity of 3-acetylaconitine and its pyrolysis products were compared,and the aconitine-induced arrhythmia model was employed to evaluate the antiarrhythmic effect of the pyrolysis ***:Two new diterpenoid alkaloids,pyroacetylaconitine and 16-epi-pyroacetylaconitine,a pair of epimers at C-16,were *** comparing the structures of these compounds,possible transformation pathways were *** with the prototype compound,3-acetylaconitine,the cardiotoxicity and acute toxicity of the heat-transformed products were significantly *** the biological activity assay,the two pyrolysis products exhibited an effective increase in ventricular premature beat latency,a reduction in the occurrence of ventricular tachycardia,as well as an increase in the rate of arrhythmia inhibition,implying strong antiarrhythmic ***:Compared with 3-acetylaconitine,its pyrolysis products displayed lower toxicity and good antiarrhythmic effects;thus,they have potential for being developed into antiarrhythmic medicines.

关键词： 3-Acetylaconitine Acute toxicity Antiarrhythmic agents 16-Epi-pyroacetylaconitine Pyroacetylaconitine Processing

BN-embedded aromatics for optoelectronic applications

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Chinese Chemical Letters 2016年第8期27卷 1139-1146,1465页

作者： jie-yu wang Jian Pei Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking University

The knowledge of azaborine chemistry is growing as an important branch in organic semiconductor ***,BN-embedded aromatic compounds have attracted great attention due to their fascinating properties resulted from the replacement of CC unit with isoelectronic BN unit in *** great insights have been provided into the synthetic chemistry and photophysical properties of BN-embedded aromatics,their applications in optoelectronic areas are still at a young *** short review summarizes the recent progress of BN-embedded aromatics with optoelectronic applications in organic field-effect transistors,organic light-emitting diodes,organic photovoltaics,stimuli-responsive luminescent devices,and chemical sensors.

关键词： Azaborine Optoelectronic device Organic semiconductor Aromatics

Embedding pyridine units in acceptors to construct donor-acceptor conjugated polymers

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Chinese Chemical Letters 2019年第1期30卷 25-30页

作者： Zi-yuan wang jie-yu wang Jian Pei Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Center for Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University

The development of donor-acceptor(D-A) conjugated polymers greatly promotes the device performance in organic electronics. Recently, the strategy of embedding pyridine units into D-A conjugated polymer backbones has attracted much attention due to the resulted lowered LUMO levels. In addition, the possible non-bonding interactions resulted from the nitrogen atoms also improve the coplanarity of the polymer backbones. All these factors have great contribution to enhance the device performance. In this review, we summarized the recent development of pyridine-embedded D-A conjugated polymers and their applications in organic field-effect transistors(OFETs).

关键词： Donor-acceptor Conjugated polymers Coplanarity Pyridine-embedded Organic electronics

Isothermal Crystallization of iPP in Environment-friendly Diluents:Effect of Binary Diluents and Crystallization Temperature on Crystallization Kinetics

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Chinese Journal of Polymer Science 2019年第6期37卷 617-626页

作者： yu-jie wang Su-Ying Yan Zhi-Ping Zhao Zhen-yu Xi School of Chemistry and Chemical Engineering Beijing Institute of Technology Environmental Protection Research Institute Beijing Research Institute of Chemical IndustrySINOPEC

The growing demand for non-toxic solvents for membrane preparation has motivated the studies for green and sustainable alternatives of solvents. The effect of droplet isothermal growth within the liquid-liquid phase separation region on isothermal spherulitic growth rate of isotactic polypropylene(iPP) was investigated. The results showed that the droplets grew up at a rate of 0.0172 μm·s^(-1). The larger droplets slowed down the isothermal spherulitic growth rate of iPP. Higher mass ratio of carnauba wax(Cwax)/soybean oil(SO)resulted in faster droplet growth due to weak interaction with polymers. The isothermal crystallization behaviors of iPP in environmentfriendly binary diluents consisting of Cwax and SO mixture were further investigated experimentally using polarized optical *** was demonstrated that the isothermal spherulitic growth rate of iPP in diluents decreased nonlinearly with the increasing crystallization temperature. Compared with virgin iPP, isothermal spherulitic growth rate of iPP in SO diluent was significantly slowed down. The spherulitic growth was further retarded after the addition of Cwax in mixed diluents, resulting in a lower crystallization rate than that in SO. Moreover, the crystal form of iPP membranes was found to be α type through the characterization of small angle X-ray scattering and wide angle X-ray diffraction.

关键词： Isotactic polypropylene Carnauba wax Isothermal crystallization kinetics PP membrane

Organic Semiconducting Materials Based on BDOPV:Structures,Properties,and Applications

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Chinese Journal of Chemistry 2020年第1期38卷 13-24页

作者： Li Ding Zi-yuan wang jie-yu wang Jian Pei College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China

What are the major current research activities of your group?To develop high performance organic semiconducting and conducting materials and also to understand their structure-property *** are also interested in the effect of the aggregation states of the con-jugated polymers on their electronic properties,the doping process and *** is the most important personality for scientific research?Curiosity and the desire to ***,one should enjoy and be happy in the process of scientific exploration.

关键词： mechanism. conducting aggregation

Deep learning characterization of rock conditions based on tunnel boring machine data

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Underground Space 2023年第5期12卷 89-101页

作者： Xu Li Min Yao Ji-dong yuan yu-jie wang Peng-yu Li Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China China Institute of Water Resources and Hydropower Research Beijing 100048China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450000China

Rock condition perception based on tunnel boring machine(TBM)data is of great importance for not only ensuring tunnel boring safety but also improving construction *** prediction of TBM boring responses(i.e.,torque and total thrust of the cutterhead)largely determines the reliability of rock condition *** this paper,a new architecture of a two-dimensional convolutional neural network(2D-CNN)with a dual-input strategy is proposed to predict the TBM *** TBM Lot 3 of the Yinsong project in Jilin province,China,is taken as the case study in this *** types of models that follow different learning strategies are compared:one is defined as the point model,which only learns data of the stable phase,and the other is defined as the line model,which learns data from both the loading and stable boring *** line model is further improved by the weighted loss function *** results indicate that the strategy of learning data from both the loading phase and stable boring phase and increasing the weight of samples from the stable phase is shown to be optimal in predicting TBM boring *** terms of learning strategies,the line model can learn the influence of active control parameters on passive response parameters,but the point model *** terms of machine learning algorithms,2D-CNN has the best performance,with R2 values of 0.865 and 0.923 for torque and total thrust,*** proposed line model can overcome the problem that the traditional model failed to learn the influence of control *** a model can provide a solid base for the timely optimization of the control parameters in TBM boring process.

关键词： TBM Rock condition perception 2D-CNN Weighted loss function Line model

Mechanistic Study on the Dominant Promotion Effect of Al-/Ti-/Zr-modifications over the VOx/SiO2 UHMWPE Catalysts

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Chinese Journal of Polymer Science 2019年第10期37卷 995-1004,I0004页

作者： yu-Long Jin Lin Liu yu-jie wang Zhen Liu Bo-Ping Liu College of Materials and Energy South China Agricultural UniversityGuangzhou 510642China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Recently, we reported the first VOx/SiO2 ethylene polymerization catalyst for making Cl-free UHMWPE, and found the dominant promotion effects of Al-/Ti-/Zr-modifications over this catalyst system(Macromol. Chem. Phys. 2017, 218, 1600443). In this work, density functional theory is applied to investigate the underlying mechanism of this remarkable promotion effect of Al-/Ti-/Zrmodifications on a molecular and atomic level. The cluster model with V(Ⅲ) is found to be the most possible active site due to its lowest overall energy barrier for monomer insertion, though the process of C2H4 coordination and the subsequent formation of transition state are most energy favored for V(Ⅱ) species. By modifying one of or both V―O―Si in the active model with V―O―M(M = Al, Ti, or Zr),the energy barrier for the binding of the upcoming C2H4 gets lower(particularly for Al-and Zr-modified catalysts), and the transition state also becomes more stable. Generally, the insertion process of C2H4 gets easier after support Al-/Ti-/Zr-modifications. This dominant promotion effect is partially ascribed to the more enriched positive charge distribution on or nearby the V center, and the narrower energy gap between the LUMO of model catalysts and the HOMO of C2H4 for these modified catalysts also contributes much. In addition, the decreased steric hindrance around the V center should be taken into account for the modified models as well. Furthermore, the Br?nsted acidity of the catalysts is investigated by introducing a pendent hydroxyl group to the model catalysts, which has a close contact with the V center. Similar promotion effect of support modification by Al, Ti, and Zr could still be observed.

关键词： Density functional theory Vanadium-oxides Ethylene polymerization Support modification Mechanism

n-Type Semiconductive Polymers Based on Pyrene-1,5,6,10-Tetracarboxyl Diimide

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Chinese Journal of Polymer Science 2023年第10期41卷 1584-1590页

作者： Xu-Dong Bai Zi-Di yu Yao Li Tian-yu Zhang Di Zhang jie-yu wang Jian Pei Da-Hui Zhao Beijing National Laboratory for Molecular Sciences Centre of Soft Matter Science and Engineering and Key Lab of Polymer Chemistry&Physics of Ministry of EducationCollege of ChemistryPeking UniversityBeijing100871China

Donor-acceptor(D-A)conjugated polymers comprising electron-deficient aromatic dicarboximide units represent an important type of organic semiconductors,especially for electron transporting ***-1,5,6,10-tetracarboxyl diimide(PyDI),a new PAH dicarboximide molecule recently reported by us,provides a fine balance between the electron-stabilizing ability andπ-stacking tendency,as compared to the naphthalenediimide(NDI)and perylenediimide(PDI)*** this study,using thienylene-vinylene-thienylene(TVT)and biselenophene(BS)as the electron donating comonomer,along with PyDI as the acceptor moiety,we develop two new D-A type conjugated polymers,which exhibit impressive electron-transporting ***,in the solution-processed OFET devices,electron mobility of 0.18 and 0.20 cm^(2)·V^(−1)·s^(−1) are achieved with these polymers,*** findings further prove the optimal potential of PyDI for application as an electron-acceptor building block in the development of polymeric n-type semiconductors among all various high-performance functional D-A polymers.

关键词： Pyrenedimide Conjugated polymers Donor-acceptor Organic electronics

On-Line Multichannel Raman Spectroscopic Detection System For Capillary Zone Electrophoresis

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Chinese Chemical Letters 2001年第3期12卷 265-266页

作者： Zhong LI yu jie wang Guo Quan LIU Yi CHEN Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

An on-line multichannel Raman spectroscopic detection system for capillary electrophoresis was established by using an Ar+ laser and a cryogenically cooled ICCD. Resonant excitation Raman spectra of methyl red and methyl orange were employed to test the system. The result shows that it could yield on-line electrophoretogram and time series of Raman spectra.

关键词： Raman spectroscopy capillary electrophoresis online coupling methyl orange methyl red