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91.
The novel complex [Zn2(Mba)3(Phen)2EtOH)]·ClO4 (Hmba=methoxybenzoic acid, Phen=1,10-phenanthroline, EtOH=ethanol) was synthesized by hydrothermal reactions, and its structure was determined by X-ray diffraction. The crystal belongs to the triclinic system, space group P with a=1.15362(1), b=1.3655(3), c=1.61451(1) nm, α=72.842(2), β=83.259(3), γ=72.083(2)°, V=2.3112(6) nm3, Z=2, μ(MoKα)=11.71 cm-1, F(000)=1120, R=0.0552 and wR=0.1157 (I > 2·(I)). The two centric zinc(Ⅱ) ions in the complex locate in a distorted octahedral coordination geometry and a distorted trigonal bipyramid coordination geometry, respectively. Two bridging bidentate carboxyl groups and a μ2-O carboxyl group from three methoxybenzoic acids act as the bridge to link two Zn(Ⅱ) ions. The asymmetric units are connected by π-π packing interactions between aromatic rings to form a three-dimensional supramolecular network. The experimental results show a good fluorescence property for the complex.  相似文献   
92.
微波辐射下,8-羟基喹啉与三环己基氢氧化锡反应,合成了三环己基锡配合物Cy3SnOC9NH6(Cy为环己基)。 通过UV、IR、1H和13C NMR、元素分析及X射线单晶衍射等技术手段表征结构。 实验结果表明,该配合物属三斜晶系,空间群P1,晶体学参数:a=0.99530(5) nm,b=1.01129(5) nm,c=2.58327(13) nm,α=89.1880(10)°,β=86.6290(10)°,γ=81.2490(10)°,Z=4,V=2.5654(2) nm3,Dc=1.326 Mg/m3,μ(MoKα)=1.013 mm-1,F(000)=1064,R1=0.0447,wR2=0.0891。 配合物在200 ℃以下稳定,对人体的癌细胞Colo205、HepG2、MCF-7和NCI-H460增殖均有较强的抑制作用。  相似文献   
93.
2-羰基丙酸水杨酰腙与二丁基氧化锡反应, 合成了二丁基锡2-羰基丙酸水杨酰腙配合物, 经元素分析、1H NMR、13C NMR、IR、UV-Vis和X射线单晶衍射等技术手段表征分子结构, 结构分析表明, 该配合物晶体属四方晶系, 锡与配位原子形成变形五角双锥构型的双核有机锡配合物, 分子以Sn2O2四元环为中心对称。 热分析结果表明, 在空气氛下, 配合物在103 ℃以下可稳定存在; 研究了配合物在近生理条件下与DNA的相互作用, 用紫外光谱、荧光光谱法及粘度法研究了配合物与鲱鱼精DNA的相互作用, 结果表明, 配合物与鲱鱼精DNA作用方式为插入结合。  相似文献   
94.
二(2,4-二氯苄基)二氯化锡分别与对甲氧基苯甲酰肼缩2-丁酮酸或2-噻吩酰肼缩2-丁酮酸酸反应,合成了两个二(2,4-二氯苄基)锡配合物(C1、C2),通过傅里叶变换红外光谱仪(FTIR)、核磁共振波谱仪(NMR)、高分辨质谱仪(HRMS)以及X射线单晶衍射(SCXRD)等表征了配合物结构。 两个配合物分子均为双锡核分子,以Sn2O2四元环为中心对称,且锡原子与配位原子形成七配位畸变五角双锥构型。 配合物C1、C2在空气氛围,120 ℃以下可稳定存在。 配合物C1、C2对人肺癌细胞(NCI-H460)、人肝癌细胞(HepG2)和人乳腺癌细胞(MCF7)均有较好的抑制作用,配合物C1略优于C2。 配合物C1、C2通过插入结合方式与小牛胸腺DNA相互作用,并且配合物C1与DNA的作用略强于C2。  相似文献   
95.
合成了3个有机锡9-芴酮-4-甲酸酯:三苯基锡9-芴酮-4-甲酸酯[(C6H5)3Sn(C14H7O3)](1)、三环己基锡9-芴酮-4-甲酸酯[(C6H11)3Sn(C14H7O3)](2)和三(2-甲基-2-苯基丙基)锡9-芴酮-4-甲酸酯[(C6H5C(CH3)2CH2)3Sn(C14H7O3)](3)。通过元素分析、红外光谱、核磁共振谱(1H、13C和119Sn)、热重分析进行了表征;用单晶X射线衍射方法测定了化合物的晶体结构,并对其进行了量子化学计算和体外抗...  相似文献   
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98.
Two series of new dinuclear rare‐earth metal alkyl complexes supported by indolyl ligands in novel μ‐η211 hapticities are synthesized and characterized. Treatment of [RE(CH2SiMe3)3(thf)2] with 1 equivalent of 3‐(tBuN?CH)C8H5NH ( L1 ) in THF gives the dinuclear rare‐earth metal alkyl complexes trans‐[(μη211‐3‐{tBuNCH(CH2SiMe3)}Ind)RE(thf)(CH2SiMe3)]2 (Ind=indolyl, RE=Y, Dy, or Yb) in good yields. In the process, the indole unit of L1 is deprotonated by the metal alkyl species and the imino C?N group is transferred to the amido group by alkyl CH2SiMe3 insertion, affording a new dianionic ligand that bridges two metal alkyl units in μη211 bonding modes, forming the dinuclear rare‐earth metal alkyl complexes. When L1 is reduced to 3‐(tBuNHCH2)C8H5NH ( L2 ), the reaction of [Yb(CH2SiMe3)3(thf)2] with 1 equivalent of L2 in THF, interestingly, generated the trans‐[(μη211‐3‐{tBuNCH2}Ind)Yb(thf)(CH2SiMe3)]2 (major) and cis‐[(μη211‐3‐{tBuNCH2}Ind)Yb(thf)(CH2SiMe3)]2 (minor) complexes. The catalytic activities of these dinuclear rare‐earth metal alkyl complexes for isoprene polymerization were investigated; the yttrium and dysprosium complexes exhibited high catalytic activities and high regio‐ and stereoselectivities for isoprene 1,4‐cis‐polymerization.  相似文献   
99.
《中国化学快报》2023,34(12):108355
Replicating extraordinarily high membrane transport selectivity of protein channels in artificial channel is a challenging task. In this work, we demonstrate that a strategic application of steric code-based social self-sorting offers a novel means to enhance ion transport selectivities of artificial ion channels, alongside with boosted ion transport activities. More specifically, two types of mutually compatible sterically bulky groups (benzo-crown ether and tert-butyl group) were appended onto a monopeptide-based scaffold, which can order the bulky groups onto the same side of a one-dimensionally aligned H-bonded structure. Strong steric repulsions among the same type of bulky groups (either benzo-crown ethers or tert-butyl groups), which are forced into proximity by H-bonds, favor the formation of hetero-oligomeric ensembles that carry an alternative arrangement of sterically compatible benzo-crown ethers and tert-butyl groups, rather than homo-oligomeric ensembles containing a single type of either benzo-crown ethers or tert-butyl groups. Coupled with side chain tuning, this social self-sorting strategy delivers highly active hetero-oligomeric K+-selective ion channel (5F12BF12)n, displaying the highest K+/Na+ selectivity of 20.1 among artificial potassium channels and an excellent EC50 value of 0.50 μmol/L (0.62 mol% relative to lipids) in terms of single channel concentration  相似文献   
100.
A series of racemic 6,6’-[(6,6’-dimethyl-[1,1’-biphenyl]-2,2’-diyl)bis(nitrylomethilidyne)]-bis(2-R1-4-R2-phenol) proligands ( L1H2 , R1=R2=Me; L2H2 , R1=tBu, R2=Me; L3H2 , R1=R2=cumyl; L4H2 , R1=CPh3, R2=Me) were reacted with {Mg[N(SiMe3)2]2}2 to provide mononuclear and dinuclear magnesium complexes [ L1 2Mg2] ( 1 ), L2–4 Mg ( 2 – 4 ), { L1 – 3 [MgN(SiMe3)2]2} ( 5 – 7 ). Complexes 3* and 4* in which each metal center is coordinated with a THF molecule were obtained when the corresponding crude complexes were recrystallized with a mixture of THF and n-hexane. Similarly, the formation of THF coordinated structure 7* of the heteroleptic dinuclear complex 7 was identified. The molecular structures of complexes 3* , 6 and 7* were established by X-ray single crystal diffraction studies, which show that mononuclear complex 3* possesses a five-coordinated metal center adopting a distorted square pyramid configuration, the two metal centers of the dinuclear complex 6 are bridged by two phenoxy oxygen atoms and each has a four-coordinated distorted tetrahedral configuration, and each metal center of the dinuclear complex 7* is still four-coordinated upon the coordination of THF but without bridging to each other. All complexes were investigated for the ring-opening polymerization (ROP) of rac-lactide (rac-LA) at 60 °C in toluene or tetrahydrofuran. Compared with the mononuclear counterparts, the dinuclear magnesium silylamido complexes showed significantly higher activities.  相似文献   
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