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排序方式: 共有19条查询结果,搜索用时 31 毫秒
1.
A new coordination polymer (CP), namely, poly[[diaquatris[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]bis[μ6‐4‐(2,4‐dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O}n, has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single‐crystal X‐ray diffraction. It presents a three‐dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz‐d net and point symbol (43)2(46·618·84). The 4‐(2,4‐dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4? SBUs into two‐dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4‐bis(1H‐imidazol‐1‐yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail.  相似文献   
2.
周成勇  朱苗力  杨频 《有机化学》2006,26(6):831-834
报道了一种对称平行的多酰胺分子——二[1-甲基-4-(1-甲基-4-硝基吡咯-2-酰胺基)吡咯-2-酰胺基乙基]胺的合成方法, 以期对DNA序列进行新的特异性识别和切割, 从而研制新型有效的工具酶或抗癌药物. 合成方法简便易行、耗时短、不需过柱分离, 每步合成都有较高产率.  相似文献   
3.
Coordination polymers (CPs) built by coordination bonds between metal ions/clusters and multidentate organic ligands exhibit fascinating structural topologies and potential applications as functional solid materials. The title coordination polymer, poly[diaquabis(μ4‐biphenyl‐3,4′,5‐tricarboxylato‐κ4O3:O3′:O4′:O5)tris[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene‐κ2N3:N3′]dicopper(II)dicopper(I)], [CuII2CuI2(C15H7O6)2(C12H10N4)3(H2O)2]n, was crystallized from a mixture of biphenyl‐3,4′,5‐tricarboxylic acid (H3bpt), 1,4‐bis(1H‐imidazol‐1‐yl)benzene (1,4‐bib) and copper(II) chloride in a water–CH3CN mixture under solvothermal reaction conditions. The asymmetric unit consists of two crystallographically independent Cu atoms, one of which is CuII, while the other has been reduced to the CuI ion. The CuII centre is pentacoordinated by three O atoms from three bpt3− ligands, one N atom from a 1,4‐bib ligand and one O atom from a coordinated water molecule, and the coordination geometry can be described as distorted trigonal bipyramidal. The CuI atom exhibits a T‐shaped geometry (CuN2O) coordinated by one O atom from a bpt3− ligand and two N atoms from two 1,4‐bib ligands. The CuII atoms are extended by bpt3− and 1,4‐bib linkers to generate a two‐dimensional network, while the CuI atoms are linked by 1,4‐bib ligands, forming one‐dimensional chains along the [20] direction. In addition, the completely deprotonated μ4‐η1111 bpt3− ligands bridge one CuI and three CuII cations along the a (or [100]) direction to form a three‐dimensional framework with a (103)2(10)2(42.6.102.12)2(42.6.82.10)2(8) topology via a 2,2,3,4,4‐connected net. An investigation of the magnetic properties indicated a very weak ferromagnetic behaviour.  相似文献   
4.
朱苗力  卢丽萍  杨频 《化学学报》2004,62(8):783-788
二甲双胍盐酸盐、硝酸盐及与Zn2+, Cu2+, Ni2+三种金属离子配合物的结构特点、电荷分布和二甲双胍配合物对四氧嘧啶糖尿病小鼠血糖影响的研究表明:Zn2+配合物表现为较为少见的单齿配位,而Cu2+, Ni2+配合物表现为双齿配位.进一步电荷分布计算发现,与端基N原子相比,二甲双胍的桥基N原子具有较高的负电荷.三种金属离子配合物对四氧嘧啶糖尿病小鼠血糖的影响研究显示,桥基N配位掩蔽后,二甲双胍的降血糖功能丧失.说明桥基N对二甲双胍的降血糖作用具有重要意义.  相似文献   
5.
通过水热法合成了一种金属有机骨架[Cd3(L)2(H2O)9]·9H2O(MOF 1),其中H3L=5-(((4-羧基苯基)氧基)甲基)苯-1,3-二甲酸,并通过单晶X射线衍射、粉末X射线衍射和元素分析对其进行了表征。MOF 1表现为一个二维微孔结构,孔隙可利用体积为22.4%。荧光性能研究表明,MOF 1可以用作检测Fe(Ⅲ)和Cr(Ⅵ)的荧光传感器。它具有高选择性和低检测限,而且不受其他离子的干扰。此外,通过金属有机骨架主体和目标分析物客体的紫外可见吸收光谱研究了主体配合物的选择性荧光猝灭机制。这种荧光猝灭的可能机制是荧光共振能量转移。  相似文献   
6.
HPLC同时测定清胃黄连丸中的4种有效成分   总被引:1,自引:0,他引:1  
建立同时测定清胃黄连丸中栀子苷、黄芩苷、小檗碱和巴马汀含量的HPLC方法。结果表明,栀子苷、黄芩苷、小檗碱和巴马汀分别在2.07—66.2μg/mL(r=0.9997)、2.72—86.9μg/mL(r=0.9998)、2.23—71.3μg/mL(r=0.9998)、2.13—68.1μg/mL(r=0.9998)范围内与峰面积呈良好的线性关系;平均回收率分别为103.2%(RSD=3.27%)、106.7%(RSD=2.46%)、103.5%(RSD=2.13%)、95.7%(RSD=2.68%)。该方法简便可行、重现性好、能更好的控制清胃黄连丸的质量。  相似文献   
7.
目前对青翘含量的研究取得了一定的成果,但关于不同炮制方法对青翘质量的影响还没有相关文献报道.本文采用分辨率高、准确度好,简便快捷、无污染的FTIR光谱法鉴别不同炮制方法对青翘质量的影响,研究了山西青翘使用不同方法和不同时间炮制后的FTIR光谱特征.结果表明,青翘共有峰为12处,其峰的数目、形状及相对强度可用于区分青翘的...  相似文献   
8.
Reaction of ZnCl2 and 4-amino-3,5-propyl-1,2,4-triazole(dpatrz) or CdCl2, NaN3 and dpatrz, in aqueous solution at room temperature yields two neutral clusters: a dinuclear complex [Zn2(dpatrz)2Cl4](I) and a linear trinuclear complex, [Cd3(dpatrz)4(N3)2Cl4](Ⅱ). Both complexes have been characterized by X-ray single-crystal diffraction, powder XRD, IR, elemental analysis, TG and fluorescence analysis. Complex I crystallizes in orthorhombic, space group Pbca with a = 11.865(2), b = 14.464(3), c = 15.985(3) , V = 2743.4(9) 3, Z = 4, C16H32N8Cl4Zn2, Mr = 609.4, Dc = 1.475 g·cm3, μ = 2.16 mm-1, F(000) = 1248, GOOF = 1.091, the final R = 0.0295 and wR = 0.0665 for 1999 observed reflections(I 2σ(I)). Complex Ⅱ crystallizes in monoclinic, space group P21/c with a = 11.408(2), b = 15.211(3), c = 18.152(6) , β = 123.75(2)o, V = 2619.1(1) 3, Z = 2, C32H64N22Cl4Cd3, Mr = 1236.05, Dc = 1.567 g·cm3, μ = 1.46 mm-1, F(000) = 1244, GOOF = 1.042, the final R = 0.0444 and wR = 0.0913 for 3466 observed reflections(I 2σ(I)). The analysis of X-ray revealed that both structures lie about the inversion centers: complex I adopts two μ1,2-triazole bridges linking two Zn(Ⅱ) ions and Ⅱ forms a linear trinuclear structure with four μ1,2-triazoles and two μ1,1-N3- bridging modes. There are different coordinated geometries for three Cd(Ⅱ) ions in Ⅱ: one is coordinated with an octahedral environment, and the other two are distorted tetragonal pyramids(τ = 0.34). The hydrogen bonds of C–H···Cl and N–H···Cl lead to the discretes into a 3D supramolecular network in both compounds. The thermal stabilities and photoluminescence behaviors of them were also studied.  相似文献   
9.
覃事栋  冯思思  张红梅  朱苗力  杨频 《化学学报》2005,63(13):1155-1160,i001
报道六齿配体N,N,N',N'四(2-苯并咪唑亚甲基)-1,2-乙二胺(EDTB)及单核镍(Ⅱ)配合物[Ni(EDTB)]·2Cl·CH3OH·C2H5OH的合成、晶体结构和SOD模拟活性.该配合物为三斜晶系,P1-空间群,a=1.0931(2)nm,b=1.1693(2)nm,c=1.6756(4)nm,a=76.042(3)°,β=88.787(3)°,γ=72.044(3)°,V=1.9740(7)nm3,Dc=1.321 g/cm3,Z=2,F(000)=824,μ=0.670mm-1.最终因子R[I>2σ(I)]R1=0.0011,wR2=0.1497;R(全部数据)R1=0.0870,wR2=0.1604.结构分析表明,镍(Ⅱ)分别与配体中的四个苯并咪唑氮和两个亚胺基氮配位形成扭曲的八面体构型.改良的邻苯三酚自氧化活性测定表明,该配合物具有较高的SOD模拟活性.  相似文献   
10.
Six two‐dimensional (2D) coordination polymers (CPs), namely, poly[{μ5‐3,3‐[(5‐carboxylato‐1,3‐phenylene)bis(oxy)]dibenzoato‐κ6O1:O1′:O3,O3′:O5:O5′}bis(N,N‐dimethylformamide‐κO)lanthanide(III)], [Ln(C21H11O8)(C3H7NO)2]n, with lanthanide/Ln = cerium/Ce for CP1 , praseodymium/Pr for CP2 , neodymium/Nd for CP3 , samarium/Sm for CP4 , europium/Eu for CP5 and gadolinium/Gd for CP6 , have been prepared by solvothermal methods using the ligand 3,3′‐[(5‐carboxy‐1,3‐phenylene)bis(oxy)]dibenzoic acid (H3cpboda) in the presence of Ln(NO3)3. The complexes were characterized by single‐crystal X‐ray and powder diffraction, IR spectroscopy, elemental analysis and thermogravimetric analysis (TGA). All the structures of this family of lanthanide CPs are isomorphous with the triclinic space group P and reveal that they have the same 2D network based on binuclear LnIII units, which are further extended via interlayer C—H…π interactions into a three‐dimensional supramolecular structure. The carboxylate groups of the cpboda3? ligands link adjacent LnIII ions and form binuclear [Ln2(RCOO)4] secondary building units (SBUs), in which each binuclear LnIII SBU contains four carboxylate groups from different cpboda3? ligands. Moreover, with the increase of the rare‐earth Ln atomic radius, the dihedral angles between the aromatic rings gradually increase. Magnetically, CP6 shows weak antiferromagnetic coupling between the GdIII ions. The solid‐state luminescence properties of CP2 , CP5 and CP6 were examined at ambient temperature and CP5 exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.53, 0.31), with luminescence quantum yields of 22%. Therefore, CP5 should be regarded as a potential optical material.  相似文献   
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