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81.
Yan Yang Liu-Ting Yan Xu-Jian Luo Rong-Huan Qin Wen-Gui Duan 《Supramolecular chemistry》2013,25(11):810-818
Three novel coordination polymers, [Co(NH2-Aip)(H2Bibim)] n (1), [Co(NH2-Aip)(HBibimop)] n √ nH2O (2) and [Mn(NH2-Aip) √ H2O] n √ 2nH2O (3) with NH2-Aip and similar benzimidazole derivative ligands (NH2-Aip = 5-aminoisophthalic acid, H2Bibim = 2,2′-bibenzimidazole and HBibimop = 1,3-bis(benzimidazol-2-yl)-2-oxapropane), have been synthesised under hydrothermal conditions and structurally characterised by single-crystal X-ray diffraction analysis, elemental analysis and IR spectroscopy. 5-Aminoisophthalic acid ligand adopts μ2-, μ3- and μ4-bridge coordination fashion and benzimidazole derivatives exist as terminal- and bridge-mode in complexes 1–3. The intricate hydrogen bonds and π–π stacking interactions in supramolecular framework are discussed. Using the combination of ultraviolet–visible absorption titration and fluorescence spectra, the experimental results show that complexes 1 and 2 bind to DNA in an intercalative mode and their DNA-binding constants (K b ) are also found. 相似文献
82.
83.
An atom-economic route to densely functionalized thiophenes has been developed via base-catalyzed rearrangement of 5-propargyl-2H-thiopyran-4(3H)-ones involving tandem retro-thio Michael addition, propargyl isomerization, and intramolecular thio-addition to allenes. 相似文献
84.
Wenbo Wu Dr. Guohua Xu Prof. Conggang Li Prof. Gui Yu Prof. Yunqi Liu Prof. Cheng Ye Prof. Jingui Qin Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6874-6888
Through the combination of the divergent and convergent approaches, coupled with the utilization of the powerful Sharpless “click‐chemistry” reaction, two series of sulfonyl‐based high‐generation NLO dendrimers were conveniently prepared with high purity and in satisfactory yields. Thanks to the perfect three‐dimensional (3D) spatial isolation from the highly branched structure and the isolation effect of the exterior benzene moieties and the interior triazole rings, these dendrimers exhibited large second harmonic generation coefficient (d33) values up to 181 pm V?1, which, to the best of our knowledge, is the highest value so far for polymers containing sulfonyl‐based chromophore moieties. Meanwhile, compared with the nitro‐chromophore‐based analogues, their optical transparency and NLO stability were improved in a large degree, due to the lower dipole moment (μ) and the special main‐chain structure of sulfonyl‐based chromophore in these dendrimers. 相似文献
85.
Qin Dai Carl Walkey Warren C. W. Chan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(20):5193-5196
In protein‐rich environments such as the blood, the formation of a protein corona on receptor‐targeting nanoparticles prevents target recognition. As a result, the ability of targeted nanoparticles to selectively bind to diseased cells is drastically inhibited. Backfilling the surface of a targeted nanoparticle with polyethylene glycol (PEG) molecules is demonstrated to reduce the formation of the protein corona and re‐establishes specific binding. The length of the backfilled PEG molecules must be less than the length of the ligand linker; otherwise, PEG interferes with the binding of the targeting ligand to its corresponding cellular receptor. 相似文献
86.
Xing-Wei Yang Xu-Jie Qin Yun-Li Zhao Paul K. Lunga Xiao-Nian Li Shi-Zhi Jiang Gui-Guang Cheng Ya-Ping Liu Xiao-Dong Luo 《Tetrahedron letters》2014
Three novel ring-fused monoterpenoid indole alkaloids, alstolactines A–C (1–3), were isolated from the long-term stored leaves of Alstonia scholaris. Their structures were identified on the basis of extensive spectroscopic data and X-ray diffractions. Moreover, the absolute configurations of these related structures were indicated by the crystal X-ray diffractions (Mo Kα) of 1a, a chlorinated derivative of 1. 相似文献
87.
Shuai Guo Ling Qiu Yanming Wang Xuzhen Qin Hui Liu Manwen He Yaping Zhang Zhili Li Xiaohong Chen 《Analytical and bioanalytical chemistry》2014,406(18):4357-4370
Changes in serum lipidome and in tissue lipidome are associated with cancer. In this study, tissue mass spectrometry imaging (MSI) and serum lipid profiling by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) were performed to investigate significantly changed lipids in both tumor (malignant thyroid cancer (MTC) and benign thyroid tumor (BTT)) tissues and sera. Y-scatterplots of variable importance in the projection (VIP) values vs. fold change values indicate that change trends in the levels of ten lipids (i.e., phosphatidylcholine (PC)(34:1), PC(36:1), PC(38:6), phosphatidic acid (PA) (36:2), PA(36:3), PA(38:3), PA(38:4), PA(38:5), PA(40:5), and sphingomyelin (SM)(34:1)) in both tissues and sera from MTC patients, BTT patients, and normal individuals are significantly associated with these three types of pathophysiological status. In order to examine their diagnostic ability, 289 serum samples from 124 MTC patients, 43 BTT patients, and 122 normal controls were randomly divided into the training set and validation set. A biomarker of PC(34:1) exhibited excellent diagnostic ability to differentiate both MTC and BTT patients from normal individuals, with an area under the receiver operating characteristic (ROC) curve value of 0.984, a sensitivity of 96.4 %, and a specificity of 92.7 %. A panel which included PA(36:3) and SM(34:1) could distinguish between MTC and BTT, with an area under receiver operating characteristic curve (AUC) of 0.961, a sensitivity of 87.8 %, and a specificity of 92.9 %. It is worth noting that a panel consisting of PC(34:1), PA(36:3), and SM(34:1) could differentiate MTC patients from both BTT patients and normal individuals, with an AUC of 0.841, a sensitivity of 86.6 %, and a specificity of 75.5 %. Figure
Comparison of tissue lipid Profiling and serum lipid profiling using MALDI-FTICR MS to select thyroid disease-specific lipids 相似文献
88.
89.
Qin Kaiwei Guo Lei Ming Shujun Zhang Shoute Guo Yanbin Pang Lei Li Tao 《Catalysis Surveys from Asia》2022,26(2):115-128
Catalysis Surveys from Asia - The catalytic performances and mechanism differences of model catalysts Cu–SSZ-13 and Fe–SSZ-13 with similar metal content and Si/Al ratio were compared.... 相似文献
90.
Science China Chemistry - Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to... 相似文献