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One-pot Two-Step Cycloaddition Reaction for Convenient Synthesis of Polycyclic Spirooxindole-fused [1,3]Oxazines

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Chinese Journal of Chemistry 2015年第9期33卷 1049-1056页

作者： jing Sun Hui Gong Chaoguo yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The novel spirooxindoline fused [1,3]oxazines were efficiently synthesized from Diels-Alder reaction of N-arylmaleimides with 1,2-dihydro-2-oxospiro[3H-indole-3,2＇-[2H,9aH-pyrido[2,1-b][l,3]oxazines], which were generated in situ from three-component reactions of substituted pyridines and isatins with methyl propiolate, or di- methyl acetylenedicarboxylate. The stereochemistry of the products was clearly clarified by the analysis of 1H NMR data and single crystal structures of the obtained polycyclic compounds.

关键词： Diels-Alder reaction one-pot reaction diastereoselectivity spirooxindole oxazine maleimide

Theoretical study of interactions between human adult hemoglobin and acetate ion by polarizable force field and fragmentation quantum chemistry methods

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Science China Chemistry 2009年第11期52卷 1925-1931页

作者： yan XiuFen JIANG Nan MA jing School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of MOENanjing UniversityNanjing 210093China

A series of theoretical approaches,including conventional FF03 and FF03-based polarization model,as well as the generalized energy-based fragmentation(GEBF) quantum chemistry method,have been applied to investigate the interactions between acetate ion(CH3COO-) and the α-subunit of human adult hemoglobin(designated as Hb-α) at four binding sites(Lys16,Lys90,Arg92,and Lys127),*** FF03-based polarizable force fields show that the interaction energies between the CH3COO-group and Hb-α follow the trend of Arg92>Lys127>Lys90>*** complexation of CH3COO-with Hb-α is governed by the long-range electrostatic interactions and steric effect.

关键词： polarization model fragmentation QM method hemoglobin interaction

Preparation and Immunogenicity of Serogroup B Meningococcal OS-OMPC Conjugates

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Biomedical and Environmental Sciences 1999年第4期12卷 296-303页

作者： SUNYIN－yan HUXU－jing InstituteofEpidemiologyandMicrobiology ChineseAcademyofPreventiveMedicineBeijing102206 InstituteofEp

The objective of the present study is to purify oligosaccharides (OSs) from serogroup B meningococci (3407 or 542852) with common lipooligosaccharide (LOS) immunotypes prevalent in China and to successtully conjugate them to their outer membrane protein complexes (OMPCs).Conjugates possessing broad cross-reactivity with different serogroup B meningococci were *** LOSs from the above two strains were purified on a Sephghex G75 column and hydrolyzed with acetic acid, and then the pare OSs were obtained by using a Sephadex G50 chromatographic column. The pure OSs were conjugated to corresponding OMPCs by carbodiimide mediated condensation. Mice were immunized with the OS-OMPC conjugates to produce antibodies. Immunognicities of the conjugates were tested by EUSA, bactericidal test and Western-blotting. The titers of antibodies against OS and LOS elicited by the two OS-OMPC conjugates increased respectively by 2. 5and 2 to 10 times as compared with those of antibodies against unconjugated OS and LOS. The sera elicited by the conjugates possessed a stronger bactericidal activity to the stndus (3407, 542852,29021) with the same LOS immunotype than to the strain with different LOS immunotype (86155).The results determined by ELISA indicated that the sera against the conjugaes showed strong response to the strains with the same or different LOS immunotypes. It was confirmed by westem-blotting analysis that the sera elicited by the two conjugates reacted with 42, 39 and 26 kDa proteins from the OMPC. Among the reactive bands, the 42kDa proteins were class 1 OMPs. The two serogroup B meningococcal OMPCs were strong immunogens and good carriers coupling with OSs as well. The immunogencity of the conjugaed OS was increased and the OS-OMPC conjugates of the serogroup B meogingococci showed a broad antigenic response to the strains tested.

关键词： outer membrane protein chromatographic column bactericidal activity acetic acid

Convenient Synthesis of Spiro[benzo[d]pyrrolo[2,1-b]thiazole- 3,2＇-indenes] Derivatives via Three-Component Reaction

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Chinese Journal of Chemistry 2016年第4期34卷 412-418页

作者： Guoliang Shen jing Sun Chaoguo yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The three-component reaction of N-phenacylbenzothiazolium bromides, aromatic aldehydes and indane-l,3- dione in ethanol at room temperature in the presence of triethylamine as base afforded functionalized spiro[benzo- [d]pyrrolo[2,1-b]thiazole-3,2＇-indenes] in good yields and with high diastereoselectivity. The 1H NMR data and sin- gle crystal structure clearly indicated that the obtained spiro compounds predominately have one diastereoisomer.

关键词： multicomponent reaction nitrogen ylide spiro compound benzothiazole indan-1,3-dione

Preparation of Molecularly Imprinted Electrochemical Sensor for Detection of Vincristine Based on Reduced Graphene Oxide/Gold Nanoparticle Composite Film

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Chinese Journal of Chemistry 2016年第12期34卷 1268-1276页

作者： yan Zhang jing Zheng Mandong Guo College of Chemistry and Material Science Shanxi Normal University Linfen Shanxi 041004 China

An innovative molecularly imprinted electrochemical sensor was fabricated based on reduced graphene oxide （RGO） and gold nanocomposite （Au） for rapid detection of vincristine （VCR）. The RGO-Au composite membrane was obtained via direct one-step electrodeposition technique of graphene oxide （GO） and chloroauric acid （HAuCl4） on the surface of a glassy carbon electrode （GCE） by means of cyclic voltammetry （CV） in the potential range be- tween -1.5 and 0.6 V in phosphate buffer solution （PBS） of pH 9.18, which is capable of effectively utilizing its superior electrical conductivity, larger specific surface area due to its synergistic effect between RGO and Au. The molecularly imprinted polymers （MIPs） were synthesized on the RGO-Au modified glassy carbon electrode surface with VCR as the template molecular, methyl acrylic acid （MAA） as the functional monomer, and ethylene glycol maleic rosinate acrylate （EGMRA） as a cross-linker. The performance of the sensor was investigated by cyclic voltammetry （CV）, differential pulse voltammetry （DPV） and electrochemical impedance spectroscopy （EIS） in de- tail. Under the optimum conditions, the fabricated sensor exhibited a linear relationship between oxidation peak current and VCR concentration over the range of 5.0×10 8 5.0×10^-6 mol.L l with a correlation coefficient of 0.9952 and a detection limit （S/N=3） of 2.6×10 8 mol.L^-1. The results indicated that the imprinted polymer films exhibited an excellent selectivity for VCR. The imprinted sensor was successfully used to determine VCR in real samples with recoveries of 90%-- 120% by using the standard addition method.

关键词： molecularly imprinted polymers electrochemical sensor reduced graphene oxide and gold nanocom-posites vincristine

lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用

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中国组织工程研究 2025年第5期29卷 928-935页

作者：白静张雪任燕李月辉田晓宇唐山中心医院口腔科河北省唐山市063000 唐山市丰润区人民医院河北省唐山市063000 开滦(集团)有限责任公司唐家庄医院河北省唐山市063000 遵化市人民医院河北省遵化市064200

背景:LncRNA-TNFRSF13C是B细胞发育和功能中的一个重要因子,在牙周炎患者牙周组织中高表达,但具体机制还不清楚。目的:探讨lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用机制。方法:人牙周膜细胞经过脂多糖处理后分为7... 详细信息

背景:LncRNA-TNFRSF13C是B细胞发育和功能中的一个重要因子,在牙周炎患者牙周组织中高表达,但具体机制还不清楚。目的:探讨lncRNA-TNFRSF13C调控miR-1246对牙周细胞低氧诱导因子1α的作用机制。方法:人牙周膜细胞经过脂多糖处理后分为7组:A组(无转染的人牙周膜细胞株)、B组(人牙周膜细胞株转染TNFRSF13C NC-siRNA)、C组(人牙周膜细胞株转染TNFRSF13C-siRNA)、D组(人牙周膜细胞株转染miR-1246 mimics)、E组(人牙周膜细胞株转染miR-1246 siRNA)、F组(人牙周膜细胞株转染TNFRSF13C-siRNA+miR-1246 mimics)及G组(人牙周膜细胞株转染TNFRSF13C-siRNA+miR-1246 siRNA)。采用qRT-PCR检测各组细胞lncRNA-TNFRSF13C、miR-1246相对表达;CCK-8检测细胞活性;流式细胞仪检测细胞凋亡率;免疫印迹检测细胞中低氧诱导因子1α、血管内皮生长因子蛋白的表达;Pearson分析lncRNA-TNFRSF13C与miR-1246相关性,双荧光素酶分析靶向关系。结果与结论:①A、B两组人牙周膜细胞活性、凋亡率及蛋白指标比较差异均无显著性意义(P>0.05),与B组相比,C组细胞活性升高、凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白降低(P<0.05),与C组相比,D组细胞活性降低,凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白均升高(P<0.05),D组相比,E组细胞活性升高(P<0.05),F组细胞活性低于E组,E、F组细胞凋亡率降低(P<0.05),与F组相比,G组细胞活性升高、凋亡率及低氧诱导因子1α、血管内皮生长因子蛋白降低(P<0.05)。②lncRNA-TNFRSF13C与miR-1246呈现正相关(P<0.05)。③TNFRSF13C-siRNA组与TNFRSF13C-NC组在miR-1246-wt荧光活性降低(P<0.05);与miR-1246-NC组相比,miR-1246 mimics组低氧诱导因子1α-wt、血管内皮生长因子-wt荧光活性升高(P<0.05)。④结果说明,下调lncRNA-TNFRSF13C对脂多糖处理的牙周细胞具有促进活性、降低凋亡的作用,同时也可抑制低氧诱导因子1α、血管内皮生长因子的表达,其机制与调控miR-1246活性相关。

关键词：牙周炎牙周膜细胞脂多糖炎症 miR-1246 lncRNA-TNFRSF13C

Three-Component Reaction for Construction of Spiro[indoline- 3,7＇-thiazolo[3,2-a]pyridines] and Spiro[benzo[4,5]- thiazolo[3,2-a]pyridine-3,3＇-indolines]

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Chinese Journal of Chemistry 2015年第12期33卷 1371-1379页

作者： Fan yang jing Sun Chaoguo yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou Jiangsu 225002 China

The three-component reaction of thiazole （benzothiazole）, dialkyl but-2-ynedioate, and isatinylidene malononi- triles in toluene at 110-120 ℃ in a sealed tube afforded a mixture of cis/trans-isomers of functionalized di- astereoisomeric spiro[indoline-3,7＇-thiazolo[3,2-a]pyridines] and spiro[benzo[4,5]thiazolo[3,2-a]pyridine-3,3＇-in- dolines] in good yields. Both cis-isomers and trans-isomers were successfully separated out and fully characterized with spectroscopy and single crystal determination. Under similar conditions, the three-component reaction con- taining 2-（1,3-dioxo-lH-inden-2（3H）-ylidene）malononitrile resulted in spiro[indene-2,7＇-thiazolo[3,2-a]pyridine] derivatives.

关键词： multicomponent reaction spirooxindole thiazole benzothiazole electron-deficient alkyne malononi-trile

Retrieval of Eddy Thermal Conductivity in the Weakly Nonlinear Prandtl Model for Katabatic Flows

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Journal of Meteorological Research 2017年第5期31卷 965-975页

作者： Bing yan Sixun HUANG jing FENG Institute of Meteorology and Oceanography National University of Defense Technology State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration

Because the nonlinearity of actual physical processes can be expressed more precisely by the introduction of a non- linear term, the weakly nonlinear Prandtl model is one of the most effective ways to describe the pure katabatic flow （no backgrotmd flow）. Features of the weak nonlinearity are reflected by two factors： the small parameter c and the gradually varying eddy thermal conductivity. This paper first shows how to apply the Wentzel-Kramers-Brillouin （WKB） method for the approximate solution of the weakly nonlinear Prandtl model, and then describes the retrieval of gradually varying eddy thermal conductivity from observed wind speed and perturbed potential temperature. Gradually varying eddy thermal conductivity is generally derived from an empirical parameterization scheme. We utilize wind speed and potential temperature measurements, along with the variational assimilation technique, to de- rive this parameter. The objective function is constructed by the square of the differences between the observation and model value. The new method is validated by numerical experiments with simulated measurements, revealing that the order of the root mean squre error is 10-2 and thus confirming the method＇s robustness. In addition, this me- thod is caoable of anti-interference, as it effectivelv reduces the influence of observation error.

关键词： weakly nonlinear Prandtl model parameter retrieval variational method Wentzel-Kramers-Brillouin(WKB) method

Dispersion features of pollutants in a compound channel with vegetated floodplains

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Journal of Hydrodynamics 2022年第6期34卷 1095-1105页

作者： yan-fang Zhao jing-jing Fan Wei-jie Wang Han-qing Zhao Fei Dong Zhen Han Shi-yan Wang School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan056038China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing210024China

The planting of the vegetation on the floodplain helps the ecological restoration,which is the main form of the river’s ecological ***,the current research of the river dynamics focuses on the water movement under a compound channel with the vegetated *** simulated vegetation species are selected in this paper for the flume simulation experiments of the floodplain vegetation,and the compound channel is divided into three subregions in the transverse *** Navier-Stokes equation and the eddy viscosity theory are applied to obtain the transverse distribution of the depth-averaged velocity and the results agree well with the experimental *** paper proposes a new method based on the analytical solution of the flow velocity distribution to calculate the average flow velocity in each *** results can effectively simulate the average flow velocity of the measured *** description of the pollutant transport processes in a moving stream requires a refined determination of the dispersion coefficients in the compound *** process of the pollutant concentrations in each zone and the reasons for their occurrence are elucidated on the basis of the experimental ***,the measured values of the longitudinal dispersion coefficients are obtained by the“routing procedure,”and a two-zone model of the pollutant dispersion is constructed on the basis of the hydrodynamic *** prediction method for the longitudinal dispersion coefficients is also *** the predicted and measured section average flow velocities to the two-zone model to predict the longitudinal dispersion coefficient,and the average relative errors are only 4.17%,7.15%,*** result indicates that the two-zone model can effectively predict the longitudinal dispersion *** calculation methods for the longitudinal dispersion coefficients from—various studies are *** results reveal that the p

关键词： Compound channel floodplain vegetation velocity distribution pollutant transport dispersion coefficient