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991.
Wanhua Lei Dr. Guoyu Jiang Dr. Qianxiong Zhou Dr. Yuanjun Hou Prof. Baowen Zhang Prof. Xuexin Cheng Prof. Xuesong Wang 《Chemphyschem》2013,14(5):1003-1008
Nanoscaled coordination polymers based on biologically prevalent ions have potential applications in drug delivery and biomedical imaging. Herein, coordination polymer nanoparticles of anionic porphyrins, including meso‐tetra(4‐carboxyphenyl)‐porphyrin (H2TCPP4?) and meso‐tetra(4‐sulfonatophenyl)‐porphyrin (H2TPPS4?), and alkaline or alkaline earth metal cations, such as K+ and Ca2+, were constructed in aqueous solution in the presence of cucurbit[7]uril (CB7) or cucurbit[8]uril (CB8). UV/Vis absorption and fluorescence spectroscopy, dynamic light scattering (DLS), scanning electron spectroscopy (SEM), and atomic force microscopy (AFM) were applied to explore the assembly and particle formation of porphyrin anions and metal cations mediated by CBn. The particle size depends on the kinds of CBn and metal cations and their concentrations. The uptake of H2TPPS4? particles by tumor cells (A549 cells) was found to be more efficient than H2TPPS4? at 37 °C, showing the application potential of such assembled particles in biology and medicine. 相似文献
992.
以氮氧自由基为配体,合成了2例未见文献报道的氮氧自由基-稀土配合物[Dy(hfac)3(NIT-C3H5)(H2O)]与[Dy(hfac)3(NIT-C3H5)]n(hfac=六氟乙酰丙酮,NIT-C3H5=2-环丙烷基-4,4,5,5-四甲基-2-咪唑啉-3-氧化-1-氧基自由基)。单晶结构分析表明配合物1为单核结构,单斜晶系P21/c空间群;配合物2为一维结构,单斜晶系P21/c空间群。交流磁化率测试结果表明配合物2虚部表现出频率依赖,这表明配合物2是单链磁体。 相似文献
993.
Concise and efficient three‐component domino [4+1+1] carbocyclization to highly substituted fluoren‐9‐one derivatives promoted by K2CO3 has been developed under microwave irradiation conditions. The direct bis‐cyanation and aryl amination residing in fluoren‐9‐one framework were achieved in a one‐pot operation. The reaction proceeds at fast rates and can be finished within 30 min, which makes workup convenient to give good to excellent chemical yields. 相似文献
994.
Wei Sun Linjie Tian Hui Qi Dan Jiang Ying Wang Song Li Junhai Xiao Xiaohong Yang 《中国化学》2013,(9):1144-1152
A series of tri-substituted chiral pyrrolidin-2-one derivatives have been designed and synthesized as CC chemokine receptor 4 (CCR4) antagonists. The structure of CCR4 was built by homology modeling. Asymmetric synthesis was applied to synthesize the R,R configuration chiral pyrrolidin-2-one scaffold. The stereoisomeric con- figurations of the compounds were identified by 2D I H-~H COSY spectroscopy and 1D NOESY spectroscopy. This method was more economical and convenient than traditional X-ray single crystal diffraction. In addition, the inter- actions between these compounds and the N-terminal extracellular tail of CCR4 were studied using capillary zone electrophoresis. The CCR4 chemotaxis inhibition effect was tested in CCR4-transfected HEK293 cells. Several compounds showed potent activities as CCR4 antagonists. Among these compounds, lc is the most active one. Its apparent binding constant of CZE experiment result is (1.569±0.11)× 10s L·mol ^-1, and its percentage inhibition of the HEK293/CCR4 cells migration with the concentration of I gmol·L ^-1 in DMSO is 59%. And compound If has slightly higher affinity to N-terminal of CCR4 according to its apparent binding constant than lb because of the in- troduced ester linkage. Further studies on the mechanism of these compounds are in progress. 相似文献
995.
A new copper and silver‐mediated cyanation of aryl iodides with DDQ as a cyanide source is achieved, providing nitriles with good yields. This new approach represents a safe method leading to aryl nitriles. 相似文献
996.
The title complex l-[CuⅡ4(Hvap)2(vap)2(MeOH)2](CIO4)2 1 has been synthesized and characterized by EA. IR,TGA,solid-state CD spectra and X-ray single-crystal analyses(l-H2vap’.a Schiff base ligand derived from the condensation of o-vanillin and l-2-amino-3-phenyl-l-propanol).Complex 1 crystallizes in monoclinic system,chiral space group P21 with a =10.4257(18).b = 21.695(4),c = 15.721(3)A,β= 94.443(3).V= 3545.1(11) 3,Z=2,Cu4C70H78N4O22Cl2.Mr= 1652.42,Dc= 1.548 g/cm3, F(000)= 1704 andμ(MoKα) = 1.338 mm-1.The final R = 0.0682 and wR = 0.1420 for 6170 observed reflections with I > 2σ(I) and R = 0.1775 and wR = 0.1830 for all data.The structure of complex 1 contains a boat-shaped(Cu4O4} motif.The solid-state CD spectra confirm the chiral nature of complex 1. 相似文献
997.
A novel supramolecular graft copolymer(SGP) composed of viologen-containing copolymer(P(DMA-co-diEV)) as the main chain and Np ended PNIPAM(Np-PN1PAm) as the grafts is prepared(DMA:N,N- dimethylacryamide,diEV:ethylviologen dimer,Np:naphthalene,PNIPAM:poly(N-isopropylacrylamide)). The grafting is based on the triple complexation among a host of cucurbit[8]uril(CB[8])and two guests of diEV and Np,which is characterized by UV-vis spectra and ITC.Temperature sensitive property of PNIPAm moiety allows SGP to self-assemble into non-covalently connected micelle(NCCM) at high temperature. The micelles are sensitive to reducing agents,for example Na2S2O3,which breaks the current inclusion complex pair and induces aggregation. 相似文献
998.
999.
采用自有的专利技术配制了复合离子交换再生剂FH-30,模拟工业锅炉软化水制备的工艺条件,研究了FH-30对软化水水质和运行周期的影响。动态模拟实验结果表明:在室温下,运行流速为35cm/min,再生剂用量不同时,运行周期基本不变,软水中钠离子和铵离子含量均随运行时间的增加而逐渐减少,当复合再生剂使用量为2.1g/mL树脂时,软化出水中的钠离子和铵离子摩尔比基本不变,复合再生剂可完全替代单一钠盐再生剂。通过对再生和失效后树脂层中钠离子和铵离子进行检测,验证了钠离子、铵离子在树脂层中没有出现累积现象。 相似文献
1000.