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Synthesis and Crystal Structure of a Zinc(II) Complex with 2-(4′-Chlorine-benzoyl)-benzoic Acid and 1,10-Phenanthroline 被引量:5
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作者 李秀梅 王庆伟 刘博 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1646-1649,共4页
A new metal-organic complex Zn2(cbba)4(phen)2 (Hcbba = 2-(4'chlorine-ben- zoyl)benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analy... A new metal-organic complex Zn2(cbba)4(phen)2 (Hcbba = 2-(4'chlorine-ben- zoyl)benzoic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The compound crystallizes in orthorhombic, space group Pbcn with a = 12.0821(II), b = 18.3140(17), c = 30.961(3) A, V= 6850.7(11) A^3, C80H48C14N4O12Zn2, Mr= 1529.76, Dc = 1.483 g/cm^3,μ(MoKa) = 0.925 mm^-1, F(000) = 3120, Z = 4, the final R = 0.0559 and wR = 0.1146 for 3963 observed reflections (I〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with three carboxylate oxygen atoms from three different cbba ligands and two nitrogen atoms from the phen ligand, showing a distorted square-pyramidal geometry. Furthermore, it exhibits a 3D supramolecular network through π-π interactions and shows yellow photoluminescent property at room temperature. 展开更多
关键词 hydrothermal synthesis crystal structure zinc(ii) complex
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Hydrothermal Synthesis, Crystal Structure and Photoluminescent Property of a Zinc(II) Complex with 2,2′-Diphenic Acid and 2,2′-Bipyridine Ligands 被引量:2
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作者 王秀艳 李秀梅 +3 位作者 牛艳玲 王庆伟 刘博 王志涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1702-1706,共5页
A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence s... A new dinuclear complex [Zn(dpa)(bipy)(H2O)]2 (dpa = 2,2'-diphenic acid, bipy = 2,2'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 10.960(2), b = 9.4841(18), c = 20.599(4), β = 104.452(3)o, V = 2073.4(7)3, C48H36N4O10Zn2, Mr = 959.55, Dc = 1.537 g/cm3, μ(MoKα) = 1.225 mm-1, F(000) = 984, Z = 2, the final R = 0.0364 and wR = 0.0843 for 2788 observed reflections (I 〉 2σ(I)). In the crystal structure, the zinc atom is five-coordinated with two carboxylate oxygen atoms from different dpas, one coordinated water molecule and two nitrogen atoms from bipy ligands, showing a slightly distorted triangular bipyramidal geometry. Furthermore, it exhibits a zero-dimensional network structure with a sixteen-membered ring and shows yellow photoluminescent property at room temperature. 展开更多
关键词 hydrothermal synthesis crystal structure zinc(ii) complex LUMINESCENCE
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Synthesis, Crystal Structure and Calculated β Value of a Tetrahedral Zinc (II) Complex——Zn(2-NH_2py)_2Br_2 被引量:3
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作者 REN Peng a SU Nan-Bing a QIN Jin-Gui a Michael W. Day b CHEN Chuang-Tianc ( aDepartment of Chemistry, Wuhan University, Wuhan 43007, China) ( bBeckman Institute, California Institute of Technology, Pasadena, CA91125, USAQ ) ( cBeijing R & D Center 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第1期38-41,共4页
A new zinc(II) complex, Zn(2-NH2py)2Br2 (py=pyridine), has been synthesized, and its molecular structure has been confirmed by IR, elemental analysis and -ray crystal structure analysis. Its space group is P21/n with... A new zinc(II) complex, Zn(2-NH2py)2Br2 (py=pyridine), has been synthesized, and its molecular structure has been confirmed by IR, elemental analysis and -ray crystal structure analysis. Its space group is P21/n with Mr=413.43 (C10H12Br2N4Zn), a=7.435(2), b=12.865(3), c=14.186(4)? b=94.08(2)? V=1353.5(5) 3, Z=4, Dc=2.029 g/cm3, F(000)=328, ?2.378mm-1, R=0.0283, wR=0.0501. The total observed reflections with I≥2?I) were 5314, of which the independent reflections were 3106. The complex structure contains a distorted tetrahedron formed by four atoms coordinated to zinc atom, namely two bromide atoms and two nitrogen atoms. The two ZnBr bond lengths within one molecule, 2.3763(6) and 2.4002(5)? respectively, are not equal; and so are the two ZnN bond lengths, which are 2.031(2) and 2.044(2)?respectively. The calculation results using PM3 method through MOPAC software package in Chem 3D show that its first molecular hyperpolarizability b value is 5.210-30esu, which is comparable with that of p-nitroaniline. No bulk SHG effect has been detected due to the centrosymmetric space group. 展开更多
关键词 zinc (ii) complex SYNTHESIS crystal structure nonlinear optical material
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Synthesis and Crystal Structure of Zinc(II) Complex with Isonicotinate Containing a Three-dimensional Hydrogen-bond Network 被引量:8
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作者 沈良 刘加庚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期253-255,共3页
A zinc complex, [Zn(iso)_2(H_2O)_4](iso=C_6H_4NO_2^-), was synthesized and characterized by elemental analysis, thermal analysis and IR spectrum studies. The crystal structure of the complex was determined by X-ray di... A zinc complex, [Zn(iso)_2(H_2O)_4](iso=C_6H_4NO_2^-), was synthesized and characterized by elemental analysis, thermal analysis and IR spectrum studies. The crystal structure of the complex was determined by X-ray diffraction. The crystal crystallizes in the triclinic system, molecular formula ZnC12H16N2O8, Mr=381.64, space group P with a = 6.338(1), b =6.919(1), c=9.277(1), α=96.28(1), β=104.91(1), γ=112.85(1)°, V=352.12(9)?3, Z=1, Dc=1.80g?cm-3 and F(000)=196, μ =1.791mm-1. The crystal structure was solved by direct methods for final R=0.0204 and Rw=0.0542 for 1258 observed reflections with [Fo>4σ(Fo)]. The crystal structure reveals that zinc ion is trans-octahedral with two pyridyl nitrogens and two aque oxygens at the equational positions and two aqua oxygens at the axial positions. The complex forms a three-dimensional network through intermolecular hydrogen bonds. 展开更多
关键词 ISONICOTINATE zinc complex crystal structure H-bonded network
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Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone 被引量:5
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作者 YU Qing ZHU Li-Gang BIAN He-Dong DENG Ji-Hua YANG Xiao-E GUO Gui-Quan LIANG Hong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1271-1275,共5页
The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analys... The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group PI with a = 7.529(3), b = 10.206(4), c = 14.678(6)A, a = 86.293(6), β= 87.686(7), γ= 81.382(6)°, C28H44Cl2N16O22Zn, Mr = 1093.06, V = 1112.3(8) ,A^3 Z = 1, Dc = 1.632 g/cm^3, S = 1.089, μ(MoKa) = 0.773 mm^-1, F(000) = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint = 0.0224. The crystal structure possesses a [Zn(H2O)6]^2+ cation, two ClO4^- anions and four PNOSs. In the crystal structure, Zn^2+ cation is located at the symcenter and coordinated by six water molecules. In [Zn(H2O)6]^2+, an elongate octahedral complex cation, the average Zn-O bond length is 2.087(2) A. There exist a lot of H bonds in the structure, linking the cation [Zn(H2O)6]^2+, anion ClO4^- and PNOS to form a 3D network. 展开更多
关键词 zinc(Ⅱ) complex salt picolinaldehyde N-oxide SEMICARBAZONE crystal structure Schiff base
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Syntheses, Characterizations, Crystal Structures and Antibacterial Activities of Two Zinc(II) Complexes with a Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:3
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作者 余玉叶 赵国良 温一航 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1395-1402,共8页
Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol ... Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (C15HIsNO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc(Ⅱ) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria. 展开更多
关键词 O-VANILLIN P-TOLUIDINE Schiff base zinc(Ⅱ) complex crystal structure antibacterial activities
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Synthesis, Crystal Structure and Kinetic Mechanism of Thermal Decomposition of a Zinc(II) Complex with N-Salicylidene-p-toluidine 被引量:2
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作者 ZHAO Guo-Liang WEN Yi-Hang YU Yu-Ye 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期609-615,共7页
The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. Th... The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896(3), b = 12.506(2), c = 15.352(3) A,β = 114.711 (4)°, V = 2598.0(8) A^3, C28H26ZnCl2N2O2, Mr = 558.80, Z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027(19), F(000) = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections (Ⅰ 〉 2σ(Ⅰ)). In complex 1, the center Zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves. 展开更多
关键词 zinc(Ⅱ) complex N-salicylidene-p-toluidine crystal structure kinetic mechanism of thermal decomposition
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Synthesis and Crystal Structure of Dinuclear Zinc(II) Complex with 3-Me-N-oxopyridine-2-thiol 被引量:1
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作者 牛德仲 孙柏旺 +1 位作者 路再生 宋保林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第2期108-111,共4页
The complex Zn(Mept) 2 (Mept=Bis(3-methyl-oxopyridine-2-thionato)) was obtained by the reaction of MeHpt with ZnSO 4 in ethanol. A single crystal X-ray study shows that the complex bis(3-Me-oxopyridine-2-thionato)zi... The complex Zn(Mept) 2 (Mept=Bis(3-methyl-oxopyridine-2-thionato)) was obtained by the reaction of MeHpt with ZnSO 4 in ethanol. A single crystal X-ray study shows that the complex bis(3-Me-oxopyridine-2-thionato)zinc(II) (Zn 2C 24 H 24 N 4O 4S 4) is a dimer. The oxygen and sulfur atoms from Mept ligand coordinates to a zinc atom forming (3-Me-oxopyridine-2-thionato)zinc(II) monomer, and every two monomeric units are linked centrosymmetrically by two oxygen bridges. The compound Zn(Mept) 2 belongs to the monoclinic system with space group P2 1/c, a=7.7627(9), b = 10.3335(7), c=17.4528(13) , β=99.134(9)°, V=1382.2(2) 3, Z=2, M r=691.46, D c=1.661 g/cm 3, μ=2.076 mm -1 , F(000)=704, R=0\^0463, R w=0.0747 for 3378 reflections with I>2σ(I). The coordination geometry about each Zn(II) ion is a distorted trigonal bipyramid. The Zn atom is coordinated by two sulfur atoms (Zn(1)-S(1) 2.307(1); Zn(1)-S(2) 2.295(2)) and one oxygen atom (Zn-O(2A) 2.126(3)) in the equatorial plane, while the two oxygen atoms of Mept ligands (Zn(1)-O(1) 2\^050(3), Zn(1)-O(2) 2\^172(3)) occupy the axial positions with O(1)-Zn(1)-O(2) 177\^2(1)°. 展开更多
关键词 crystal structure zinc complex 3-methyl-oxopyridine-2-thione
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Synthesis,Structure,and Luminescent Property of a 3-D Zinc Complex {[Zn_8^(II)(4-APha)_8(CH_3COO)_8](CH_3CH_2OH)_2}_n 被引量:1
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作者 杨华 胡道道 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第7期1019-1024,共6页
The title complex [ZN8II(4-APha)8(CH3COO)8(CH3CH2OH)2]n (1, 4-APha = 4-ami- nophenylhydroxamic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffracti... The title complex [ZN8II(4-APha)8(CH3COO)8(CH3CH2OH)2]n (1, 4-APha = 4-ami- nophenylhydroxamic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, IR and elemental analysis. The crystal belongs to the monoclinic system, space group C2/c with a = 39.074(4), b = 9.9645(8), c=38.846(3) A, β = 136.438°, V= 10423.1(14) A3, C84H118N16O39Zn8, Mr = 2498.90, Z = 4, Dc = 1.592 g/cm3,μ= 1.900 mm-1, F(000) = 5144, the final R = 0.1036 and wR = 0.2953. This complex possesses a 3-D structure which is constructed from 1-D chain motifs linked by the 4-APha" ligands. The luminescent property of the title complex has been investigated. 展开更多
关键词 zinc complex hydroxamic acftls 3-D framework luminescent property
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Synthesis and Crystal Structure of a Tetranuclear Carboxylate-bridged Lanthanum(III)-Zinc(II) Complex [La_2Zn_2(m-CNC_6H_4COO)_(10)(Py)_2(C_2H_5OH)_2] 被引量:1
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作者 郑发鲲 郭国聪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第5期391-395,共5页
The title complex was prepared from self-assembly reaction of La(NO3)3(6H2O, Zn(NO3)2(6H2O, m-cyanobenzoic acid (m-CNC6H4COOH) and pyridine (Py) in refluxing ethanol and its structure was determined by single-... The title complex was prepared from self-assembly reaction of La(NO3)3(6H2O, Zn(NO3)2(6H2O, m-cyanobenzoic acid (m-CNC6H4COOH) and pyridine (Py) in refluxing ethanol and its structure was determined by single-crystal X-ray diffraction. Crystallographic data: C94H62N12La2O22Zn2, Mr = 2120.12, triclinic space group P, a = 13.2219(5), b = 13.2713(5), c = 14.1987(6) ?, (???69.156(1), ( = 84.034(1), ( = 89.400(1) (, V = 2314.9(2) ?3, Z = 1, Dc = 1.521 g/cm3, F(000) = 1060, ( (MoK() = 14.94 cm-1, the final R = 0.043 and wR = 0.117 for 6381 unique reflections with I > 2((I). Crystal structure determination shows that the neighboring lanthanum(III) and zinc(II) ions are bridged by three bidentate m-cyanobenzonate ligands in the syn-syn fashion to form a pair of dinuclear [LaZn(m-CNC6H4COO)3(Py)(C2H5OH)] subunits, being linked together by two bidentate and two tridentate m-cyanobenzonate groups in the syn-syn and syn-anti modes, respectively, to construct a tetranuclear La-Zn complex [La2Zn2(m-CNC6H4COO)10(Py)2(C2H5OH)2]. 展开更多
关键词 synthesis crystal structure lanthanum complex zinc complex carboxylate complex
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Elimination of GGTA1,CMAH,β4GalNT2 and CIITA genes in pigs compromises human versus pig xenogeneic immune reactions
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作者 Jing Xu Jilong Ren +11 位作者 Kai Xu Minghui Fang Meina Ka Fei Xu Xin Wang Jing Wang Zhiqiang Han Guihai Feng Ying Zhang Tang Hai Wei Li Zheng Hu 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第4期584-590,共7页
Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to im-prove the immune compatibility between humans and pigs.Curre... Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to im-prove the immune compatibility between humans and pigs.Current knockout strat-egies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHC II molecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHC II can be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHC I and II deletion. 展开更多
关键词 CD4 T cell genetically edited pig immune rejection major histocompatibility complex ii XENOTRANSPLANTATION
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Synthesis, Characterization and DFT Studies of Two Zinc(II) Complexes Based on 2-Isopropylimidazole
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作者 Jean Jacques Anguile Odette Nana Ngnabeuye +4 位作者 Ndosiri Ndoye Bridget Tanyi Rogers Fomuta Alvine Loris Djoumbissie Alain Charly Kuate Tagne Jean Ngoune 《Open Journal of Inorganic Chemistry》 2018年第4期105-124,共20页
Two novel coordination compounds, [Zn(L)2(OOCH)2] (1) and [Zn(L)3(OCHO)](OCHO)]·H2O (2) (where L = 2-isopropylimidazole, C6H10N2) have been prepared by reaction of 2-isopropylimidazole with zinc(II) formate at ro... Two novel coordination compounds, [Zn(L)2(OOCH)2] (1) and [Zn(L)3(OCHO)](OCHO)]·H2O (2) (where L = 2-isopropylimidazole, C6H10N2) have been prepared by reaction of 2-isopropylimidazole with zinc(II) formate at room temperature using toluene as solvent. These compounds were characterized by elemental and thermal analyses, IR, 1HNMR and 13CNMR spectroscopies, single crystal X-ray diffraction and DFT studies. The Zn centers in 1 and 2 adopt pseudo-tetrahedral coordination geometries. Compound 1 crystallizes in the monoclinic system P2/c space group whereas compound 2 crystallizes in the P-1 space group of the triclinic crystal system. Several types of hydrogen intra-/intermolecular interactions are observed in these materials and extend into a two-dimensional leaf like network in 1 and a two-dimensional lattice of rectilinear pillars in 2. Compounds 1 and 2 were also optimized and their frontier molecular orbitals, global reactivity descriptors, molecular electrostatic potential, natural bond orbitals were investigated using density functional theory (DFT). In fact the induced structural differences from complex 1 to complex 2 led to the reduction of the frontier molecular orbital energy gap by 1.338 eV and a decrease of the chemical hardness by 0.669 eV. 展开更多
关键词 zinc(ii) complexES of 2-Isopropylimidazole THERMOGRAVIMETRIC Analysis 1H-MR 13C-MR Crystal Structure DFT Studies
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Synthesis and Crystal Structure of a New Complex [Bis(dien)zinc(II)] Zinc(II) Tetrachloride (dien = Diethylenetriamine)
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作者 许瑞波 许兴友 +6 位作者 施鹏飞 王大奇 高镜 杨绪杰 陆路德 汪信 徐国想 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1441-1444,共4页
The title complex [bis(dien)zinc(Ⅱ)] zinc(Ⅱ) tetrachloride was synthesized and characterized by X-ray single-crystal diffraction, elemental analysis, electric conductivity, IR and electronic spectra. The compo... The title complex [bis(dien)zinc(Ⅱ)] zinc(Ⅱ) tetrachloride was synthesized and characterized by X-ray single-crystal diffraction, elemental analysis, electric conductivity, IR and electronic spectra. The compound crystallizes in the tetragonal system, space group I^-4 with a = 10.250(3), b = 10.250(3), c = 9.054(2) V = 951.2(5)A^3, Mr = 486.95, Z = 2, F(000) = 504, Dc = 1.700 g/cm&3,μ = 3.083 mm^-1, λ. = 0.71073A, the final R = 0.0226 and wR = 0.0642. The symmetric crystal smacture consists of a zinc complex cation [Zn(dien)2]^2+ and a zinc tetrachloride aniOn [ZnC14]^2-, forming a three, dimensional framework through intrmnolecular and intermolecular hydrogen bonds. 展开更多
关键词 DIETHYLENETRIAMINE zinc tetrachloride zinc complex crystal structure
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Synthesis and Determination of Stability Constants of a New Bis-1,2,4-triazole Ligand for Complexation with Zinc(II), Copper(II) and Nickel(II) in Acetonitrile
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作者 Reza Emamali Sabzi Abbas Nikoo +3 位作者 Yaser Nikzad Morteza Bahram Karim Akbari Naser Samadi 《American Journal of Analytical Chemistry》 2012年第6期437-442,共6页
In this work, the synthesis and complexation properties of a new compound, 1,3-bis[5-(2-hydroxyphenyl)-4-phenyl- 1,2,4-triazole-3-yl-thio]propane (BTP), towards certain transition metal ions, (M(II) where M = Zn, Cu, ... In this work, the synthesis and complexation properties of a new compound, 1,3-bis[5-(2-hydroxyphenyl)-4-phenyl- 1,2,4-triazole-3-yl-thio]propane (BTP), towards certain transition metal ions, (M(II) where M = Zn, Cu, Ni) in acetonitrile is reported. A hard-modeling strategy was applied to UV-Visible spectroscopy data obtained from monitoring the reaction between BTP and the selected metal ions to determine the concentration profiles of each species and the corresponding stability constant(s) of the complex(es). The stability constants of complexes are always defined in terms of their free metal, free ligand and complexed forms. These constants are influenced by parameters such as the type of metal, ligand, counterion or solvent. In this study, the formation constants of the complexes were determined for the synthesized ligand with several metallic cations in acetonitrile solvent by UV-Vis spectrophotometry. 展开更多
关键词 ZN(ii) Cu(ii) and NI(ii) complexes Triazole LIGAND Spectrophotometry
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Synthesis and Crystal Structure of an Azide Bridged Binuclear Zinc(II) Complex Including the Reduced Derivative of Nitronyl Nitroxide, [Zn(Him2Py)(N_3)_2]_2
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作者 王利亚 张晨曦 +2 位作者 廖代正 姜宗慧 阎世平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第2期171-175,共5页
The title compound [Zn(Him2Py)(N3)2]2 (Zn2C26H38N18O2, Mr = 765.48) has been prepared and structurally characterized by X-ray diffraction methods. It crystallizes in monoclinic, space group P21/n with a = 10.989(3), b... The title compound [Zn(Him2Py)(N3)2]2 (Zn2C26H38N18O2, Mr = 765.48) has been prepared and structurally characterized by X-ray diffraction methods. It crystallizes in monoclinic, space group P21/n with a = 10.989(3), b = 11.519(3), c = 13.812(4) ? b = 101.700(5), V = 1711.9(9) ?, Z = 2, Dc = 1.485 g/cm3, m(MoKa) = 1.456 mm~1, F(000) = 792, the final R = 0.0401 and wR = 0.0861 for 2054 observed reflections with I>2s(I). The imino nitroxide 2-(3- methyl-2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl (im2Py) was reduced to obtain 2-(3-methyl -2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-ydroxy (Him2Py) coordinating to the zinc (II) ion, around which the coordination geometry is a square-based pyramid with a terminal nitrogen atom located at the apical position. The four basal sites are occupied by two m1,1 nitrogen atoms from two different bridging azide ions and two nitrogen atoms from Him2Py. The units of [Zn(Him2Py)(N3)2]2 were connected as two dimension planes by intermolecular hydrogen bonds. 展开更多
关键词 crystal structure nitronyl nitroxide radical Zn(ii) complex
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Synthesis of Branched Polyethylene via Bulky α-Diimine Nickel(II)-Catalyzed Ethylene Chain-Walking Polymerization
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作者 Zhengquan Dong Pei Li +1 位作者 Guoyong Xu Fuzhou Wang 《Open Journal of Organic Polymer Materials》 2024年第1期1-12,共12页
The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ... The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature. 展开更多
关键词 Ethylene Polymerization α-Diimine Ni(ii) complex Chain-Walking Polymerization Branched Polyethylene
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Growth Response and Metal Accumulation of Sedum alfredii to Cd/Zn Complex-Polluted Ion Levels 被引量:22
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作者 叶海波 杨肖娥 +2 位作者 何冰 龙新宪 石伟勇 《Acta Botanica Sinica》 CSCD 2003年第9期1030-1036,共7页
Sedum alfredii Hance has been identified as a new Zn-hyperaccumulator native to China. In this study, responses and metal accumulation of S alfredii were examined under Zn/Cd complex polluted conditions. The results s... Sedum alfredii Hance has been identified as a new Zn-hyperaccumulator native to China. In this study, responses and metal accumulation of S alfredii were examined under Zn/Cd complex polluted conditions. The results showed that optimal growth of S alfredii in terms of the maximum dry matter yield was observed at Zn/Cd complex level of 500/100 mumol/L. Plant cadmium (Cd) or zinc (Zn) concentrations increased with increasing Cd or Zn supply. During the 20 d treatment, the highest Cd concentration in the leaves reached 12.1 g/kg at Zn/Cd level of 50/400 mumol/L and that of Zn in the stems was 23.2 g/kg at Zn/Cd level of 1000/50 mumol/L. The distribution of Cd in different plant parts decreased in the order: leaf > stem greater than or equal to root, whereas that of Zn was: stem > leaf greater than or equal to root. The accumulation of Cd and Zn in the shoots and roots of S. alfredii increased with the increasing of Zn/Cd supply levels, peaked at Zn/Cd levels of 250/400 and 500/100 mumol/L, respectively. The highest Cd and Zn uptake by the shoots was approximately 5 and 11 mg/plant, and was over 20 and 10 times higher than those in the roots, respectively. Zn supply at levels less than or equal to 500 mumol/L increased plant Cd concentrations, whereas high Zn supply decreased root Cd but did not affect leaf Cd concentrations in S alfredii Low Cd supply increased Zn concentration in the leaves, but Cd supply higher than 50 mumol/L considerably reduced root Zn concentrations, especially at low Zn level. These results indicate that S. alfredii can tolerate high Zn/Cd complex levels and has an extraordinary ability to hyperaccumulate not only Zn but also Cd. It could provide a new valuable plant material for understanding the mechanisms responsible for co-hyperaccumulation of Zn and Cd as well as for phytoremediation of the Cd/Zn complex polluted soils. 展开更多
关键词 complex pollution cadmium (Cd) zinc (Zn) HYPERACCUMULATION Sedum alfredii
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Interactions Between Anticancer Pt(II) complexes and Human Erythrocyte Spectrin *
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作者 杨晓改 李荣昌 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第3期9-14,共6页
The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are ... The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP. 展开更多
关键词 Pt (ii) complex SPECTRIN CONFORMATION Binding sites Kinetic CHIRAL
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Hydrothermal Synthesis and Crystal Structure of a Zinc Complex:[Zn_(2.5)(phen)(BDC)_2(OH)] (phen = 1,10-Phenanthroline, BDC = Benzene-1,4-dicarboxylic Acid) 被引量:10
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作者 王庆伟 李秀梅 史林芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期11-14,共4页
A metal-organic coordination polymer [ZnE.s(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-c... A metal-organic coordination polymer [ZnE.s(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The complex crystallizes in the triclinic system, space group PI with a = 11.199(2), b = 11.593(2), c = 11.865(3)/A, α= 99.330(1), β = 111.506(1), γ = 104.804(1)^o, V= 1328.4(5)A^3, Dc= 1.722 g/cm^3, Z = 1, Mr = 1377.82, F(000) = 692,μ(MoKa) = 2.306 mm^-1, S = 1.093, R= 0.0281 and wR = 0.0756 for 4179 observed reflections (I 〉 2σ(/)). The coordination polyhedron around Zn(II) can be described as a tetrahedron, trigonal bipyramid and octahedron. It is worth noting that the crystal structure of 1 is composed of tetranuclear zinc clusters linked by {ZnO6} units. 展开更多
关键词 zinc complex hydrothermal synthesis crystal structure tetranuclear zinc cluster
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Preparation of Platinum(II) Complexes with 1-β-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide and its Deoxy-analogue 被引量:7
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作者 Wen PEI Kobe JOZE 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期559-562,共4页
The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-t... The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF. 展开更多
关键词 Platinum(ii) complexes ribavirin and deoxyribavirin nucleobase platination complexation reaction antitumor agents
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