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Radical induced quartet photosensitizers with high ^(1)O_(2) production for in vivo cancer photodynamic therapy

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Science China Chemistry 2021年第3期64卷 488-498页

作者： Feng Xu Haoying Ge Ning Xu Cheng Yang Qichao Yao Saran Long wen sun Jiangli Fan Xinsheng Xu Xiaojun Peng State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China School of Physics and Electronic Information Anhui Normal UniversityWuhu 241000China Anhui Province Key Laboratory of Optoelectric Materials Science and Technology Anhui Normal UniversityWuhu 241000China Ningbo Institute of Dalian University of Technology Ningbo 315016China

Singlet oxygen(^(1)O_(2)) is a strong oxidant which plays important roles in photodynamic therapy(PDT). The exploitation of photosensitizers with high ^(1)O_(2) production is crucial to improve PDT efficiency. In this study, a radical labeled quartet photosensitizer Cy-DENT is reported with high singlet oxygen quantum yield(Φ_(Δ)=32.3%) due to a radical enhanced inter-system crossing(ISC) process. After the introduction of 2,2,6,6-tetramethylpiperidinyloxy(TEMPO) radical, quartet state ^(4)[R,T] of CyDENT could be formed to give an over 20-fold enhancement of singlet oxygen quantum yield compared to Cy-DEN(without TEMPO radical) under irradiation of near infrared(NIR) light. In addition, the ^(1)O_(2 )production is well controlled by varying the electron-donating ability of the terminal substituent group. Cy-DENT possesses good cell permeability and is localized in mitochondria. Under the irradiation of 700 nm light, Cy-DENT can produce high levels of ROS to destroy the mitochondria membrane potential and induce cell apoptosis. Through the encapsulation of PEG-SS-PCL micelle, Cy-DENT can be effectively delivered to tumors and suppresses the tumor growth after PDT treatment.

关键词： singlet oxygen photodynamic therapy quartet photosensitizer TEMPO radical

Transition-metal-free hydroamination/defluorination/cyclization of perfluoroalkyl alkynes with amidines

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Organic Chemistry Frontiers 2022年第1期9卷 109-116页

作者： Li-wen sun Zi-Lun Yu Xin-Long Luo Mengtao Ma Zhi-Liang Shen Xue-Qiang Chu Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Department of Chemistry and Materials Science College of ScienceNanjing Forestry UniversityNanjing 210037China

An efficient defluorinative net-[3+3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was *** present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination,defluorination,and *** desired pyrimidines could be obtained with good functional group tolerance and moderate to good ***,the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative *** pendantπsystem would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp^(3))–F bond.

关键词： cyclization pyrimidine Transition

New Modified Jacobi Elliptic Function Expansion Method and Its Application to （3＋1）-Dimensional KP Equation

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Communications in Theoretical Physics 2006年第6期45卷 1063-1068页

作者： DOU Fu-Quan sun Jian-An DUAN wen-Shan SHI Yu-Ren Lü Ke-Pu HONG Xue-Ren College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China

With the aid of computerized symbolic computation, the new modified Jacobi elliptic function expansion method for constructing exact periodic solutions of nonlinear mathematical physics equation is presented by a new general ansatz. The proposed method is more powerful than most of the existing methods. By use of the method, we not only can successfully recover the previously known formal solutions but also can construct new and more general formal solutions for some nonlinear evolution equations. We choose the （3＋1）-dimensional Kadomtsev-Petviashvili equation to illustrate our method. As a result, twenty families of periodic solutions are obtained. Of course, more solitary wave solutions, shock wave solutions or triangular function formal solutions can be obtained at their limit condition.

关键词： MJEFE method KP equation periodic solutions solitary wave solutions

Identification of LmUAP1 as a 20-hydroxyecdysone response gene in the chitin biosynthesis pathway from the migratory locust, Locusta migratoria

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Insect Science 2018年第2期25卷 211-221页

作者： Xiao-Jian Liu Ya-wen sun Da-Qi Li Sheng Li En-Bo Ma[] Jian-Zhen Zhang Research Institute of Applied Biology College of Life Science Shanxi University Taiyuan China Key Laboratory of Insect Developmental and Evolutionary Biology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

In Locusta migratoria, we found that two chitin biosynthesis genes, UDP N-acetylglucosamine pyrophosphorylase gene LmUAP1 and chitin synthase gene Lm- CHS1, are expressed mainly in the integument and are responsible for cuticle formation. However, whether these genes are regulated by 20-hydroxyecdysone （20E） is still largely unclear. Here, we showed the developmental expression pattern ofLmUAP1, LmCHS1 and the corresponding 20E titer during the last instar nymph stage of locust. RNA interference （RNAi） directed toward a common region of the two isoforms of LmEcR （LmEcRcom） reduced the expression level of LmUAP1, while there was no difference in the expression of LmCHS1. Meantime, injection of 20E in vivo induced the expression of LmUAP1 but not LmCHS1. Further, we found injection-based RNAi of LmEcRcom resulted in 100% mortality. The locusts failed to molt with no apolysis, and maintained in the nymph stage until death. In conclusion, our preliminary results indicated that LmUAP1 in the chitin biosynthesis pathway is a 20E late-response gene and LmEcR plays an essential role in locust growth and development, which could be a good potential target for RNAi-based pest control.

关键词： chitin synthesis Locusta migratoria regulation RNA interference 20-hydroxyecdysone

Effects of a novel mesoionic insecticide,triflumezopyrim,on the feeding behavior of rice planthoppers,Nilaparvata lugens and Sogatella furcifera(Hemiptera:Delphacidae)

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Journal of Integrative Agriculture 2020年第10期19卷 2488-2499页

作者： ZHU Jun sun wen-qing LI Yao GE Lin-quan YANG Guo-qing XU Jian-xiang LIU Fang College of Horiculture and Plant Protection Yangzhou UniversityYangzhou 225009P.R.China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture&Agri-Product Safety Yangzhou UniversityYangzhou 225009P.R.China

The rice planthoppers,Nilaparvata lugens and Sogatella furcifera,are important sap-sucking pests of rice in *** mesoionic insecticide tifumezopyrim was previously shown to be highly effective in controlling both *** and *** this study,electropenetrography(EPG)was used to evaluate the effect of three triflumezopyrim concentrations(LC。LC。and LC)on the feeding behavior of *** and *** signals of planthoppes indicated that there were six different waveforms NP,N1,N2,N3,N4,and N5,which corresponded to non-penetration,stylet penetration into epidermis,salivation,extracellular movement of stylet,sap ingestion in phloem,and water ingestion in xylem during *** to untreated controls,triflumezopyrim at LC。and LC。prolonged the duration of the non-penetration period by 105.3 to 333.7%.The probing frequencies of *** exposed to tiflumezopyrim at LC1。and LCso were significantly increased;however,the probing frequencies of *** showed a significant decrease when exposed to triflumezopyrim at all *** exposure prolonged the duration of salivation and shortened the duration of extracellular *** duration of phloem sap ingestion decreased from 37.2 to 77.7%in the LCgo and LCgo treatments,*** in feeding behavior in response to triflumezopyrim and pymetrozine were *** summary,the results show that the LC。and LCgo concentrations of trflumezopyrim inhibit the feeding activities of *** and *** mainly by prolonging the duration of non penetration and by shortening the duration of phloem sap ingestion,which may foster more efficient use of triflumezopyrim in Asia.

关键词： Nilaparvata lugens Sogatella furcifera triflumezopyrim pymetrozine,feeding behavior EPG

Synthesis, Crystal Structure and Fungicidal Activity of Ethyl 2-(3-(4-Fluorobenzamido)phenyl)-4-((4-fluorobenzoyl)oxy)thiazole-5-carboxylate

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Chinese Journal of Structural Chemistry 2019年第6期38卷 923-929页

作者： GUO Xiao-Feng SU Han-Xiang FAN Zhi-Jin sun Xue-wen sun Yao-Zheng QIN Zhong-Xiang State Key Laboratory of Elemento-organic Chemistry College of Chemistry Nankai University

The target compound, ethyl 2-（3-（4-fluorobenzamido）phenyl）-4-（（4-fluorobenzoyl）oxy） thiazole-5-carboxylate, was synthesized by four-step procedures including N-protection, thionation, cyclization and acylation. Its structure was characterized by 1 H NMR, 13C NMR, HRMS and single-crystal X-ray diffraction. The target compound crystallizes as monoclinic crystal system, space group C2/c with a = 9.6097（19）, b = 14.246（3）, c = 33.070（7） ?, V = 4515.1（16） ?3, Z = 8, Dc = 1.496 Mg/m3, F（000） = 2096 and μ = 0.203 mm-1. There are 21864 reflections measured（4.94≤2θ≤55.96°）, of which 5357 were unique（Rint = 0.1418） and used in all calculations. The final R = 0.0581（I > 2σ（I）） and wR = 0.1453（reflections）. The target compound showed over 50% of growth inhibition against Physalospora piricola, Rhizoctonia cerealis and Sclerotinia sclerotiorum.

关键词： thiazole synthesis crystal structure fungicidal activity

A Cyanine-based Liposomal Nanophotosensitizer for Enhanced Cancer Chemo-Photodynamic Therapy

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Chemical Research in Chinese Universities 2021年第4期37卷 925-933页

作者： LI Mengqi MA He SHI Chao ZHANG Han LONG Saran sun wen DU Jianjun FAN Jiangli PENG Xiaojun State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian116024P.R.China State Key Laboratory of Fine Chemicals Shenzhen Research InstituteDalian University of TechnologyShenzhen518057P.R.China

Currently,chemotherapy is one of the most important treatment modalities for malignant tumors in the clinic,however,it exhibits some shortcomings,such as poor selectivity,limited efficacy and serious adverse ***,synergistic therapy and accurate drug delivery at tumor sites become a promising strategy for achieving tumor ***,a smart NIR fluorescence imaging-guided nanoliposome was fabricated by encapsulating a chemotherapeutic drug(doxorubicin,DOX),liposomes(L)and a near-infrared(NIR)photosensitizer(CY)to form L@CY@DOX,which could realize enhanced therapeutic efficacy of chemo-PDT in cancer therapy(PDT=photodynamic therapy).L@CY@DOX can induce mitochondrial apoptosis and produce severe toxicity at the cellular level,and L@CY@DOX can enrich in the tumor site,which significantly induces tumor *** vitro and in vivo studies demonstrated that L@CY@DOX exhibited great antitumor efficacy compared with each one of these monotherapies,indicating that the combination of chemotherapy and PDT possessed potential development prospects and is anticipated in clinical application.

关键词： Photodynamic therapy Liposome Photosensitizer Cyanine dye Doxorubicin Cancer

Influence of Monomers'Structure on the Assembly and Material Property of Pillar[5]arene-Based Supramolecular Polymer Gels

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Chinese Journal of Chemistry 2021年第12期39卷 3421-3428页

作者： Juan Liu Xiao-wen sun Ting-Ting Huang You-Ming Zhang Hong Yao Tai-Bao Wei Qi Lin College of Chemical Engineering Northwest Minzu University(Northwest University for Nationalities)Xibei XincunLanzhouGansu 730000China Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhouGansu 730070China

Pillar[5]arene-based supramolecular polymer gels(SPGs)show broad application *** investigate the influence of the supramolecular monomers'structure on the assembly and properties of corresponding pillar[5]arene-based SPGs,a series of monomers based on different functionalized pillar[5]arene derivatives with various structures were *** are per-methylated pillar[5]arene(H1),bromobutane-functionalized pillar[5]arene(H2),4-hydroxybenzaldehyde-functionalized pillar[5]arene(H3),ethyl thioglycolate-functionalized pillar[5]arene(H4),thioacetylhydrazine-functionalized pillar[5]arene(H5),bola-type bis-pillar[5]arene(H6)and tripodal-type tri-pillar[5]arene(H7).Meanwhile,a neutral tripodal-guest TG was also employed to co-assemble with these pillar[5]arene-based monomers by host-guest *** a result,under the same conditions(10%,DMSO-H_(2)O,w/v,10 mg·mL^(-1)=1%),H1 and H2 cannot assemble into SPGs with ***,mono-p[5]derivatives H3—H5 could assemble into SPGs with *** importantly,bis-p[5]H6 and tri-p[5]H7 could assemble into supramolecular polymer network gel(SPNG)and supramolecular polymer organic framework gel(SOFG)with TG,*** gels all show blue aggregation-induced emission(ALE)*** these SPGs,the SPNG shows the best viscoelastic behavior and self-healing *** result is attributed to the flexible network structure of *** addition,the xerogels of SOFG and SPNG have shown nice adsorption and separation properties for organic dyes in water solution.

关键词： Pillararerie Host-guest systems Self-assembly Aggregation Structure-activity relationships

Data Mining Ontology Development for High User Usability

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 51-56页

作者： LI Yu-hua LU Zheng-ding sun Xiao-lin wen Kun-mei LI Rui-xuan College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

This paper mainly introduces the development and implementation of the user centered data mining service ontology on Universal Knowledge Grid （UKG）. UKG is an ontology-based grid architecture model to build large-scale distributed knowledge discovery system on the grid. The data mining ontology services are the main service offering by UKG. It can meet the user requirements of knowledge discovery in different domains and different hierarchies and make the system exoteric, extensible and high usable. A data min- ing solution for money laundering is introduced.

关键词： data mining ontology usability universal knowledge grid