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Chinese Chemical Letters 2017年第5期28卷 981-985页

作者： Jin-Wei Yuan ling-bo qu School of Chemistry & Chemical Engineering Henan University of TechnologyAcademician Workstation for Natural Medicinal Chemistry of Henan Province

Direct C—H functionalization of quinoline N-oxides with arylboronic acids is achieved using KMnOas the sole and efficient oxidative *** method provides an efficient protocol to construct regioselectively 2-arylquinol... 详细信息

关键词： quinoline N-oxide Arylboronic acid KMnO_4-mediated Radical reaction Arylation

Development of ELISA and immunochromatographic assay for ofloxacin

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Chinese Chemical Letters 2007年第9期18卷 1107-1110页

作者： Wu Yong Sun Wen Ying Liu ling bo qu Department of Pharmacy China Pharmaceutical UniversityNanjing 210009China Department of Chemistry Zhengzhou UniversityZhengzhou 450052China

Two rapid, sensitive and reliable immunoassay methods, namely competitive indirect enzyme-linked immunosorbent assay (CI-ELISA) and colloidal gold-based immunochromatographic assay (CGIA), were developed to detect ofloxacin (OFL). The linear range of the CI-ELISA was from 0.5 to 128 ng/mL with a limit of detection (LOD) of 0.35 ng/mL. Good recoveries were obtained in analyzing simulated swine urine samples. The CGIA could accurately estimate OFL at concentrations as low as 10 ng/mL in less than 10 min, and test results were read visually without any instrument.

关键词： Ofloxacin (OFL) Polyclonal antibody (pAb) Competitive indirect enzyme-linked immunosorbent assay (CI-ELISA) Colloidal gold-based immunochromatographic assay (CGIA)

Novel preparation of organic polymer-based monolithic column by microwave irradiation

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Chinese Chemical Letters 2007年第11期18卷 1399-1402页

作者： Xiong Wen Ye Yu Ping Zhang ling bo qu Li qun Fan bo Li Department of Chemistry Zhengzhou University Henan 450052 China Henan Institute of Science and Technology Xinxiang 453003 China

Microwave irradiation was firstly attempted for the preparation of organic-based monoliths of poly（styrene-divinylbenzene- methacrylic acid）, which single step in situ polymerization was carried out during 15 min. The colunm permeability, electrophoretic and chromatographac behaviors were comparatively evaluated using pressure-assisted CEC, GEC and low pressure-driven separation modes. The largest theoretical plates for the preparing column could be close to 18,0000 plates/m for thiourea in the mode of p-CEC. It provided a viable alternative to traditional initiation means for the perparation of monolithic capillary columns.

关键词： Monolithic columns Microwave irradiation Electrochromatography Polymerization

AFM and fluorescence spectrascopy investigation for disaggregation of existing Aβ fibrils by baicalein

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Chinese Chemical Letters 2012年第5期23卷 595-598页

作者： Sheng Mei Song Yong Xiang Wang Li Min Xiong ling bo qu Mao Tian Xu Department of Chemistry Zhengzhou UniversityZhengzhou 450052China Henan Key Laboratory Cultivation Base of Nanobiological Analytical Chemistry Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China

The wavelength for the peak of fluorescence emission of thioflavin T（ThT） was changed from 445 nm to 481 nm when ThT was added in Aβ solution which indicating the β-sheet structure of Aβ*** significant decrease in the intensity of fluorescence at 481 nm was observed when the baicalein was added in mixed solution of Aβand ThT,suggesting that the depolymerization of Aβ fibrils happened and there were Aβ fibrils left to react with ThT to keep the initial fluorescence *** the existing Aβ fibrils are disaggregated by baicalein in a time- and dose-dependent *** images of the morphologies of the Aβ_（1-42） fibrils obviously changed smaller and more dispersive when baicalein added indicating also the depolymerization of Aβ.The results demonstrate a basis for development of a potential herb drug candidate for the treatment of Alzheimer＇s disease（AD）.

关键词： Amyloid β peptide Baicalein Fluorescence spectroscopy Atomic force microscope

Theoretical insight into phosphoric acid-catalyzed asymmetric conjugate addition of indolizines to a,β-unsaturated ketones

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Chinese Chemical Letters 2018年第8期29卷 1237-1241页

作者： Haohua Chen Lei Zhu Kangbao Zhong Xiaoyu Yue ling-bo qu Ruopeng Bai Yu Lan School of Chemistry and Chemical Engineering Chongqing University College of Chemistry and Molecular Engineering Zhengzhou University

Phosphoric acid catalysis is a powerful tool for the construction of new CààC bonds because of its unique LUMO-lowering activity. Theoretical calculations were employed to investigate phosphoric acidcatalyzed asymmetric conjugate addition of indolizines to a,b-unsaturated ketones. The calculation results showed that this transformation proceeds via a reaction pathway involving nucleophilic addition,deprotonation–aromatization, and tautomerization. The computational results showed that deprotonation–aromatization is the rate-determining step and the enantioselectivity-determining *** S-configured product was preferentially generated via a pathway starting from the s-cis conjugated ketone, whereas the s-trans isomer led to a side product with the R configuration. Non-covalent interaction analysis showed that the enantioselectivity is mainly caused by bond-rotation strain in the transition states of the deprotonation–aromatization step.

关键词： Phosphoric acid catalysis Theoretical calculations Mechanism Enantioselectivity

Regioselectivity of Pd-catalyzed o-carboranearylation: a theoretical view

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Organic Chemistry Frontiers 2022年第6期9卷 1686-1695页

作者： Jiying Liu Dongmin Fu Zitong Chen Tiantian Li ling-bo qu Shi-Jun Li Wenjing Zhang Yu Lan Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan 450001China School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China

The mechanism and the regioselectivity of Pd-catalyzed B(4)–H arylation and B(4,5)–H diarylation foro-carborane with bidentate directing groups were investigated. The complete catalytic cycle involves Pdmediated concerted metalation–deprotonation, oxidative addition, counterion exchange, and reductiveelimination, where counterion exchange is critical. The reductive elimination is the rate- and regioselectivity-determining step for the whole catalytic cycle. B(3)-Arylation is unfavorable because the stericrepulsion between the substituent group on C(2) and the metal moiety would lead to significant distortionof o-carborane and would result in a higher activation energy for reductive elimination. The distortion ofo-carborane can be clearly observed from the change of its aromaticity in the corresponding transitionstates by the calculation of nucleus-independent chemical shifts. Moreover, counterion exchange withcarboxylate before reductive elimination significantly increases the positive charge of palladium, whichleads to a lower activation free energy for the sequential step.

关键词： elimination catalyzed reductive

Selective Cyclooxygenase-2 Inhibitors: Design and Synthesis

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Chinese Chemical Letters 1999年第6期10卷 469-472页

作者： Xin Sheng LEI Zong Ru GUO ling bo qu Qi Qing ZHU(Institute of Materia Medica. Chinese Academy of Medical SciencesAnd Peking Union Medical College. Beijing 100050) Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

The discovery of COX-2 provides a novel target developing more effective NSAIDs with fewer side effects. On the basis of results from the structure-activity relationships (SAR) of selective COX-2 inhibitors, we have d... 详细信息

关键词： cyclooxygenase cyclooxygenase-2 inhibitor selective

Synthesis and thermal properties of Asymmetric Cyclotriphos-phazene-based Benzoxazine resin

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Synthesis and thermal properties of Asymmetric Cyclotriphos-...

boosting charge extraction and efficiency of inverted perovskite solar cells through coordinating group modification at the buffer layer/cathode interface

河南省化学会2016年学术年会

作者： Yan Zhu Jing Zhu Juan He Hong-Liang Wei Hui-Juan Chu Gang Wang ling-bo qu College of Chemistry and Chemical Engineering Henan University of Technology

Cyclotriphosphazene, a ring compound consisting of alternating phosphorus and nitrogen atoms with two substituents, exhibits remarkable resistance to heat, super flame retardancy. Benzoxazine resin is a new phenol formaldehyde resin(phenolic resin) evolved from the traditional resin. It not only has the heat-resistant, fire-retardant and other features, it also has the unique properties that traditional phenolic resins do not have, such as: no shrinkage during polymerization, can be cured without a catalyst, ease to be processed to desired shapes and the flexibility in the design of molecular structures. It therefore has an excellent prospects in applications. In this paper, benzoxazine structure was introduced to the phospha-zene ring in order to improve the flame retardant and heat resistance properties of the modifiled *** this paper, firstly 2,2′dihydroxybiphenyl(HOC6H4C6H4OH) was adopted for conducting partial blocking of phosphonitrilic chloride trimer(HCCP) to prepare mono-spiro phosphazenes(T1),then the p-aminophenol and salicylide were added for dehydration, preparing the schiff base which contains two phenolic hydroxyl structures, and then Na BH4 was used for the reduction of C=N double bond, after that, adding paraformaldehyde into the 1,4-dioxane system, so that the polybenzoxazines C3 of phenolic hydroxyl group can be synthesized. Finally, in the 1,4-dioxane system, the nucleophilic substitution of T1 and C3 occurred, producing the asymmetric cyclotriphosphazene-benzoxazine ***, the evaluation of thermal properties of the themoset resin demonstrated that the glass transition temperature(Tg) achieved 156°C and have a high decomposition temperature and char *** flame-retardant performance has also been investigated by LOI and UL 94 vertical burning tests,their LOI values were above 29%, and achieved a UL94 V-0 classification.

关键词： cyclotriphosphazene benzoxazine synthesis thermal properties flame-retardant performance

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Nano Research 2025年第1期18卷 415-423页

作者： Zhiqing Liang Ziqiu Ren Ziyu Wang Nan Yan ling Li bo Zhang Yanlin Song College of Chemistry Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

In inverted perovskite solar cells (PSCs),effective modification of the interface between the metalcathode and electron transport layer (ETL) is crucial forachieving high performance and stability. Herein, sulfonatedbathocuproine, commonly known as disodium bathocuproinedisulfonate (BCDS), was employed as a cathode buffer layerto address the interfacial issues at the [6,6]-phenyl-C61-butyricacid methyl ester (PCBM)/Ag interface. BCDS possesses theability to form coordinate bonds with Ag electrodes. Theutilization of the BCDS buffer layer enhanced the chargeextraction capability at the cathode interface whilesimultaneously achieving interfacial defect passivation,improving interfacial contact and increasing the built-in electricfield. Consequently, a power conversion efficiency (PCE) of25.06% was achieved. Furthermore, owing to the excellent filmforminguniformity of BCDS on PCBM, the stability of thedevice was also improved. After storage in dry air for morethan 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoringcoordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising newfrontier in buffer layer development and performance optimization strategies for PSCs.

关键词： perovskite solar cells buffer layer bathocuproine disulfonate coordination group modification electron transport layer(ETL)-cathode interface

一种用于光催化C(sp^(2))-H键官能团化通用的非均相钒酸铋催化剂

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Chinese Journal of Catalysis 2023年第3期46卷 157-166页

作者：曾繁林朱虎林王茹楠袁晓亚孙凯屈凌波陈晓岚於兵郑州大学化学学院绿色催化中心河南郑州450001

近年来,可见光诱导的有机反应条件温和、效率高,因而备受关注.由于多数有机物不能直接吸收可见光,因此需要添加具有光学活性的化合物作为光催化剂,促进反应发生.目前有机化学工作者已经发展了许多高效的光催化剂,如过渡金属(钌、铱等)... 详细信息

近年来,可见光诱导的有机反应条件温和、效率高,因而备受关注.由于多数有机物不能直接吸收可见光,因此需要添加具有光学活性的化合物作为光催化剂,促进反应发生.目前有机化学工作者已经发展了许多高效的光催化剂,如过渡金属(钌、铱等)配合物、有机染料等.然而这些光催化剂也存在一些局限,例如贵金属光催化剂价格昂贵,有机染料稳定性相对较差,而且大多数是均相催化剂,且反应后无法回收利用.从绿色化学的角度讲,针对光催化的有机反应,发展低成本、多功能、高效、可回收的非均相光催化剂具有重要意义.本文采用水热/煅烧相结合的方法合成了三种钒酸铋晶体,并通过粉末单晶衍射、紫外可见光吸收光谱、光电流实验、荧光发射光谱、扫描电镜等手段进行表征.结果表明,合成的钒酸铋属于单斜晶系,且表现出一定的光电性能.相较于市售的钒酸铋,合成的BiVO_(4)-180具有更小的粒径,呈现规则的椭圆形,在模型反应中表现出更高的光催化活性.以BiVO_(4)-180为非均相光催化剂,用于多种C(sp^(2))-H官能团化反应,实现了一系列复杂有机分子的合成和药物分子米非司酮、醋酸乌利司他的后修饰.主要涉及的有机光反应包括:N,N-二甲基芳香胺与马来酰亚胺或苄烯丙二腈的[4+2]环化反应,吲哚C-3位、α-氨基酸酯、芳烃等化合物的直接官能团化反应.此外,光催化剂的回收实验表明BiVO_(4)-180在反应后很容易回收再利用,在经过8次催化使用后,其结构和催化活性几乎未发生变化.反应机理研究表明,BiVO_(4)-180的光生电子和氧空位在上述有机光反应中起到关键作用.综上,BiVO_(4)-180作为廉价易得、稳定的非均相光催化剂,可以有效地应用在多种可见光催化的C(sp^(2))-H官能团化反应中.该策略具有反应条件温和,催化剂易制备且可回收,适用于药物修饰,底物适用性广等优点.

关键词：钒酸铋光催化非均相催化剂碳氢键官能团化自由基化学