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Chemical Research in Chinese Universities 2001年第3期17卷 237-242页

作者： LI Bao-long XU Yan LIU Yong-jiang XU Zheng coordination Chemistry Institute State Key Laboratory of Coordination ChemistryNanjing UniversityNanfing 210093P.R.China

A compound {[Co(azpy)2(NCS)2]·1/4EtOH·1/2H2O}n(1), where azpy=4,4’-azobispyridine, was synthesized and characterized by means of IR, TGA-DTA, magnetic susceptibility and X-ray single crystal diffraction. It consists of two independent sets of fully interlocked two-dimensional networks with the dihedral angle 61.7°, organized in parallel stacks of the sheets which are made of edge-shared [Co(Ⅱ)]4squares separated by 0. 9062nm, and defined size rhombic channels. The thermal gravimetric analysis indicates that the framework is stable up to 198℃. The variable-temperature magnetic susceptibility measurements indicated that there is a weak antiferromagnetic interaction between the cobalt(Ⅰ) ions in the complex (1).

关键词： Crystal structure Porous structure Cobalt complex Azobispyridine complex Thiocyanate complex

Aminolysis reaction of calix [ 4 ] arene esters and crystal structures and conformational behaviors of calix[4]arene amides

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Chinese Journal of Chemistry 2000年第1期18卷 94-103页

作者：武勇刘辉彪胡俊刘永江段春迎徐正 coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4] arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove mat 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2r isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = ?10°C, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may be of forming different hydrogen bonds.

关键词： Calixarene amides aminolysis reaction conformation crystal structure

Study on the inclusion compound of β-cyclodextrin with (η5-cyclopentadienyl)tricarbonylmanganese(0)

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Chinese Journal of Chemistry 1995年第4期13卷 311-317页

作者： SONG, Le-Xin MENG, Qing-Jin YOU, Xiao-Zengcoordination Chemistry State Key Laboratory, coordination Chemistry Institute, Nanjing University,Nanjing, Jiangsu 210093, China coordination Chemistry State Key Laboratory Coordination Chemistry Institute Nanjing University Nanjing Jiangsu 210093 China

The supramolecular inclusion compound of β-cyclodextrin (β-CD, host) with (η5-cyclopentadienyl)tricarbonylmanganese [MnCp(CO)3, guest] was obtained in a crystalline state. The host-guest compound is thermally stable and do not liberate the guest on heating at 100$ in vacuum. It was characteried by elemental analysis,1H NMR, differential scanning thermal (DSC) analysis and TLC. Continueous variation plot by NMR method shows that β-CD formed 1:1 inclusion compound with MnCp(CO)3. On the basis of 1H NMR spectra and the model building with Corey Pauling Koltum (CPK) models, the most probable inclusion mode is proposed.

关键词： Inclusion compound β-cyclodextrin supermolecule

Metal compound-mediated hydrolytic cleavage of oxidized insulin B chain:Regioselectivity and influence of peptide secondary structure

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Chinese Journal of Chemistry 2000年第6期18卷 855-862页

作者：罗雪梅何卫江张宇郭子建朱龙根 coordination Chemistry Institute State Key Laboratory of Coordination ChemistryNanjing UniversityNanjingJiangsu 210093China

The interaction of oxidized insulin B chain (B) with cis-[Pd(en)Cl2] (en=ethylenediamine), cis-[Pd-(dtco-3-OH)Cl2] (dtco-3-OH= dithiacyclooctan-3-ol) and CuCl2 was studied by electrospray mass spectrometry. It is discovered that the binding of Pd(II) complexes and the sites of cleavage are highly dependent on the secondary structure and local environment of B. The hydrolytic cleavage of denatured B by Pd(II) complexes was monitored by HPLC. The reaction is regioselective and follows first order kinetics with half-life of 4.8 days at 40oC. Two amide bonds, i. e. at Leu6-Cys7 and at Gly8-Ser9, which are dose to the two potential Pd(II) binding sites His5 and His10, are selectively cleaved. In the case of Cu(II) ion as promoter, only one cleavage site was observed which is located at Gly8-Ser9 bond. These results provide improved understanding on the design of artificial metallopeptidase.

关键词： Insulin B chain hydrolytic cleavage palladium)(II) complexes Cu(II) ion electrospray mass spectrometry

Self-assembly of a photoluminescent metal-organic cage and its spontaneous aggregation in dilute solutions enabling timedependent emission enhancement

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Science China Chemistry 2022年第6期65卷 1105-1111页

作者： Dong Luo Le-Xiong Wu Yan Zhang Yong-Liang Huang Xue-Ling Chen Xiao-Ping Zhou Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou510632China Department of Chemistry Shantou University Medical CollegeShantou515041China

Charged metal-organic cages generally produce aggregates with various morphologies and different properties through the multiple supramolecular interactions in solution. Herein, a luminescent hexahedral metal-organic cage containing pyrene chromophores is successfully constructed through coordination-driven subcomponent self-assembly. The cage exhibits novel spontaneous aggregation in a dilute solution and time-dependent luminescence enhancement behavior during the subsequent incubation process. Dynamic light scatter(DLS) and transmission electron microscopy(TEM) results prove that the metalorganic cages can form blackberry-like aggregates in methanol dilute solution. Unexpectedly, the luminescent intensity of this system shows a linear increase with the extension of the incubation time in methanol, and this process is also reflected in the change in the quantum yield of the system(2% to over 80% after 5 days incubation time). Ultraviolet-visible(UV-vis),1 H nuclear magnetic resonance(1 H NMR) and mass spectra show that metal-organic cages can stably exist in dilute solution. Timedepended DLS and TEM data reveal that the aggregates of metal-organic cages are gradually changed from the dense state to the loose one, which may involve the transition of the system from an energy unstable state to a stable one, probably leading to the unusual time-dependent luminescent property. This unique time-dependent luminescent cage aggregate can be potentially applied as a “supramolecular time meter”.

关键词： self-assembly metal-organic cage spontaneous aggregation time-dependent emission enhancement pyrene

Structure and electrospray mass spectrometry studies on dithiacyclooctan-3-ol-containing palladium (II) complex of trans -[Pd(dtco-3-OH)_2](ClO_4)_2·2DMSO

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Chinese Journal of Chemistry 2000年第1期18卷 49-53页

作者：罗雪梅刘永江梅毓华朱龙根 coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

The structure of trans-[Pd(dtco-3-OH)2] (ClO4)2·2DMSO, in which dtco-3-OH is dithiacyclooctan-3-ol and DMSO is dimethyl sulfoxide, was determined by X-ray crystallographic analysis. The crystal data: space group pi, a = 0.7077(2) nm, b = 1.0788(1) nm, c = 1.1111(1) nm, α=67.710(8)°, β = 73. 59(2)°, γ = 85. 39(2)°,R1 = 0 . 0368 and Rw = 0.0998. The palladium (II) is coordinated by four sulfur atoms with a regular square planar configuration. The Pd-S distances are 0.2314(1) and 0.2317(1) nm, respectively. Both dtco-3-OH ligands are in the boat-chair configuration and two hydroxyl groups are on the opposite sites of the PdS4 coordination plane and are towards Pd(II). The Pd-O distance is 0. 285 nm, indicating a weak interaction between them. A typical hydrogen bond between the hydroxyl group of dtco-3-OH ligand and DMSO was observed in the crystal structure. An aqueous solution prepared with the crystals of the complex was used for the investigation of electrospray mass spectrometry ( ESMS ). Besides trans -[ Pd ( dtco-3-OH)2]2+. 2DMSO observed, in the full scan spectrum of ESMS, all relative species of it, which were probably produced during electrospray ionization process, were also detected. From these experiments, it reveals that ESMS is a powerful tool for studying noncovalent interaction present in solution between inorganic complexes and solvents.

关键词： Palladium (Ⅱ) complex dithiacyclooctan-3-ol crystal structure electrospray mass spectrometry

Synthesis and Crystal Structure of a Two-dimensional Framework Supramolecular Complex [Mn(phen)(DPZDA)(H_2O)]·2H_2O

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Chinese Journal of Structural Chemistry 2006年第12期25卷 1431-1434页

作者：孙亚光谷晓夫高恩君陈尚东 Laboratory of coordination Chemistry Shenyang Institute of Chemical Technology

A novel two-dimensional supramolecular complex [Mn（phen）（DPZDA）（H2O）]·2H2O has been synthesized by the reaction of Mn（CH3COO）2, 1,10-phenanthroline （phen） and H2DPZDA （3,5-dimethyl-pyrazine-2,6-dicarboxylic acid）. Elemental analysis, IR spectra and X-ray singlecrystal diffraction were carried out to determine the composition and crystal structure of the title complex. Crystal data： triclinic system, space group P1, a = 7.7474（13）, b = 9.3381（15）, c = 15.146（3） A, α = 93.872（3）, β= 102.451 （11 ）, y = 105.261 （ 11）°, C20H20MnN4O7, Mr = 483.34, Z = 2, F（000） = 498, V=1023.2（3）A^3, Dc=1.569 g/cm^3,μ=0.697 mm^-1, -9≤h≤9, -11≤k≤10, -18≤l≤12, R = 0.0365 and wR=0.0901 for 3585 independent reflections （Rint= 0.0165） and 2923 observed reflections （I〉 2σ（I））. Structural analysis indicates that Mn（Ⅱ） adopts a distorted octahedral geometry. The 2-D framework supramolecular structure of the title complex is constructed from hydrogen bonds and π…π interactions.

关键词： Mn(Ⅱ) crystal structure weak interaction supramolecule

Multimodal Fraudulent Website Identification Method Based on Heterogeneous Model Ensemble

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China Communications 2023年第5期20卷 263-274页

作者： Shengli Zhou Linqi Ruan Qingyang Xu Mincheng Chen Information Department of Zhejiang Police College Hangzhou 310053China Zhejiang Branch of National Computer Network Emergency Response Technical Team/coordination Center of China(CNCERT/ZJ) Hangzhou 310052China

The feature analysis of fraudulent websites is of great significance to the combat,prevention and control of telecom fraud *** to address the shortcomings of existing analytical approaches,*** dimension and venerability to anti-reconnaissance,this paper adopts the Stacking,the ensemble learning algorithm,combines multiple modalities such as text,image and URL,and proposes a multimodal fraudulent website identification method by ensembling heterogeneous *** is first used in the training of multiple largely different base classifiers that are strong in learning,such as BERT model,residual neural network(ResNet)and logistic regression *** of the text,image and URL features are then performed *** results of the base classifiers are taken as the input of the meta-classifier,and the output of which is eventually used as the final *** study indicates that the fusion method is more effective in identifying fraudulent websites than the single-modal method,and the recall is increased by at least 1%.In addition,the deployment of the algorithm to the real Internet environment shows the improvement of the identification accuracy by at least 1.9%compared with other fusion methods.

关键词： telecom fraud crime fraudulent website data fusion deep learning

Synthesis and Crystal Structure of a 2D coordination Polymer:[Nd_2(PDB)_2(CH_3COO)_2(H_2O)_3]

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Chinese Journal of Structural Chemistry 2008年第1期27卷 112-116页

作者：谷晓夫孙亚光高恩君阎晓梅 Laboratory of coordination Chemistry Shenyang Institute of Chemical Technology

A novel coordination polymer [Nd2（PDB）2（CH3COO）2（H2O）3] （H2PDB = pyridine3,4-dicarboxylic acid） has been synthesized by the reaction of Nd（CH3COO）3 with pyridine3,4-dicarboxylic acid under hydrothermal conditions. Elemental analysis, IR spectra and X-ray crystal structure analysis were carried out to determine the composition and crystal structure of the title complex which belongs to the triclinic system, space group P^-1 with a = 6.9409（14）, b = 7.5497（15）, c = 22.530（5）A, α = 84.79（3）, β = 88.15（3）, γ= 75.55（3）^o, C18H18N2O15Nd2, Mr = 790.82, Z = 2, V = 1138.5（4） A^3, Dc = 2.307 g/cm^3,μ = 4.593 mm^-1, -6≤h≤8, -5≤k ≤8, -26≤l≤ 26, F（000） = 760, Rint = 0.0298, R= 0.0314 and wR= 0.0695 （I〉 2σ（I））. Nd（1） and Nd（2） are linked into zigzag chains by carboxylate groups of acetate with interesting μ3-η^2：η^2 fashion. The zigzag chains are bridged by PDB to form a 2D framework, and a 3D supramolecular network is further constructed via π-π stacking.

关键词： Nd(Ⅲ) crystal structure coordination polymer

SYNTHESIS, CHARACTERIZATION OF IMIDAZOLATE-BRIDGED HETEROPOLY- NUCLEAR COMPLEXES AND THEIR ACTIVITY IN DISMUTATION OF O^(-)_(2)

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Science China Chemistry 1991年第8期34卷 897-907页

作者：唐雯霞陈东刘之俊戴安邦 coordination Chemistry Institute Nanjing University

A series of imidazolate-bridged heteropolynuclear complexes containing Cu2+ or Zn2+ were synthesized and characterized by reflectance spectroscopy, NMR and X-ray diffraction analysis. The bonding nature and the stability of imidazolate bridges in the complexes were studied by ESR spectroscopy, and the catalytic activity of the complexes in dismutation of O-2 was determined by NBT method. Results obtained indicate that the central Cu with N4 and N2O2 square planar or N4O square pyramidal coordination in which there is a weak bond H2O or ClO-4 on axial position, has a comparatively higher activity, but that with N5 square pyramidal having a strong bond axial ligand has almost no activity. Thus the results imply a possible formation of Cu-O-2 intermediate adduct in the catalytic process by Cu, Zn-SOD.

关键词： copper zinc imidazolate-bridged complex dismutalion of O-2.