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51.
Sébastien Thiery Céline Declairieux Denis Tondelier Gijun Seo Bernard Geffroy Olivier Jeannin Rémi Métivier Joëlle Rault-Berthelot Cyril Poriel 《Tetrahedron》2014
We report a structure–property relationship study of four 9,9′-spirobifluorene (SBF) derivatives (4-5Pm-SBF, 2-5Pm-SBF, 4-Ph-SBF and 2-Ph-SBF), substituted with either phenyl or pyrimidine at the C2 or C4 position of the SBF core. Structural, thermal, electrochemical and photophysical properties have been examined and correlated to theoretical calculations in order to study the influence of the nature and the position of the substituent. The emission properties of 4- versus 2-substituted SBFs are noticeably different highlighting, in the excited state, the remarkable effect of substitution in ortho position of SBF. All compounds have been used as host material for green dopant in PhOLEDs with very high performances (2-5Pm-SBF: CE>58 cd/A, PE>35 lm/W, EQE>14%). More importantly, the two 4-substituted SBFs have been used as host materials in blue PhOLEDs, displaying high performance and a decrease of VTH for 4-5Pm-SBF due to the incorporation of the electron-withdrawing pyrimidine. 相似文献
52.
Absolute quantitation of host cell proteins in recombinant human monoclonal antibodies with an automated CZE‐ESI‐MS/MS system
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Guijie Zhu Liangliang Sun Travis Linkous Dawn Kernaghan James B. McGivney IV Norman J. Dovichi 《Electrophoresis》2014,35(10):1448-1452
We report the first use of CZE for absolute characterization of host cell proteins (HCPs) in recombinant human monoclonal antibodies. An electrokinetically pumped nanoelectrospray interface was used to couple CZE with a tandem mass spectrometer. Three isotopic‐labeled peptides (LSFDKDAMVAR, VDIVENQAMDTR, and LVSDEMVVELIEK) were synthesized by direct incorporation of an isotope‐labeled lysine or arginine. The heavy‐labeled peptides were spiked in the HCP digests at known concentrations. After CZE‐ESI‐MS/MS analysis, the peaks of native and isotopic‐labeled peptides were extracted with mass tolerance ≤ 5 ppm from the electropherograms, and the ratios of peak area between native and isotopic‐labeled peptides pairs were calculated. Calibration curves (the ratios of peak area versus spiked peptide amount) with R2 values of 0.999, 0.997, and 0.999 were obtained for the three HCP peptides, and the absolute amounts of the three proteins present were determined to be at the picomole level in a 20 μg sample of digested HCPs. The target proteins were present at the 7–30 ppt level in the purified HCP samples. 相似文献
53.
4,4′-bis(N-carbazolyl)tolan (BCT) and 4,4′-bis[N-(3,6-di-t-butyl)carbazolyl]tolan (BCT-t-Bu) were synthesized as π-expanded analogs of 4,4′-bis(N-carbazolyl)biphenyl. Their photophysical characteristics both in solution and films were thoroughly investigated. Interestingly, the phosphorescence spectrum of BCT was significantly medium-dependent, and the emission maximum was red-shifted by 131 nm from 489 nm in solution at 77 K to 620 nm in a deposited film at 5 K, suggesting the presence of strong intermolecular interactions in the film. BCT and BCT-t-Bu were found to be useful as host materials for fluorescence-based organic light emitting diodes (OLEDs). However, their low triplet energy levels in films negated their potential to act as hosts in phosphorescence-based OLEDs. 相似文献
54.
Dr. Krzysztof M. Bąk Sophie C. Patrick Dr. Xiaoxiong Li Prof. Paul D. Beer Prof. Jason J. Davis 《Angewandte Chemie (International ed. in English)》2023,62(14):e202300867
Mimicking Nature's polymeric protein architectures by designing hosts with binding cavities screened from bulk solvent is a promising approach to achieving anion recognition in competitive media. Accomplishing this, however, can be synthetically demanding. Herein we present a synthetically tractable approach, by directly incorporating potent supramolecular anion-receptive motifs into a polymeric scaffold, tuneable through a judicious selection of the co-monomer. A comprehensive analysis of anion recognition and sensing is demonstrated with redox-active, halogen bonding polymeric hosts. Notably, the polymeric hosts consistently outperform their monomeric analogues, with especially large halide binding enhancements of ca. 50-fold observed in aqueous-organic solvent mixtures. These binding enhancements are rationalised by the generation and presentation of low dielectric constant binding microenvironments from which there is appreciable solvent exclusion. 相似文献
55.
Dr. Weichao Xue Dr. Kai Wu Nianfeng Ouyang Dr. Thierry Brotin Prof. Dr. Jonathan R. Nitschke 《Angewandte Chemie (International ed. in English)》2023,62(18):e202301319
Self-assembly of a flexible tritopic aniline and 3-substituted 2-formylpyridine subcomponents around iron(II) templates gave rise to a low-spin FeII4L4 capsule, whereas a high-spin FeII3L2 sandwich species formed when a sterically hindered 6-methyl-2-formylpyridine was used. The FeII4L4 cage adopted a new structure type with S4 symmetry, having two mer-Δ and two mer-Ʌ metal vertices, as confirmed by NMR and X-ray crystallographic analysis. The flexibility of the face-capping ligand endows the resulting FeII4L4 framework with conformational plasticity, enabling it to adapt structurally from S4 to T or C3 symmetry upon guest binding. The cage also displayed negative allosteric cooperativity in simultaneously binding different guests within its cavity and at the apertures between its faces. 相似文献
56.
Keisuke Wada Misaki Suzuki Dr. Takahiro Kakuta Prof. Dr. Tada-aki Yamagishi Dr. Shunsuke Ohtani Dr. Shixin Fa Dr. Kenichi Kato Prof. Dr. Shigehisa Akine Prof. Dr. Tomoki Ogoshi 《Angewandte Chemie (International ed. in English)》2023,62(19):e202217971
Controlling dynamic chirality and memorizing the controlled chirality are important. Chirality memory has mainly been achieved using noncovalent interactions. However, in many cases, the memorized chirality arising from noncovalent interactions is erased by changing the conditions such as the solvent and temperature. In this study, the dynamic planar chirality of pillar[5]arenes was successfully converted into static planar chirality by introducing bulky groups through covalent bonds. Before introducing the bulky groups, pillar[5]arene with stereogenic carbon atoms at both rims existed as a pair of diastereomers, and thus showed planar chiral inversion that was dependent on the chain length of the guest solvent. The pS and pR forms, regulated by guest solvents, were both diastereomerically memorized by introducing bulky groups. Furthermore, the diastereomeric excess was amplified by crystallization of the pillar[5]arene. The subsequent introduction of bulky groups yielded pillar[5]arene with an excellent diastereomeric excess (95 % de). 相似文献
57.
Peiren Liu Fang Fang Haochen Wang Prof. Niveen M. Khashab 《Angewandte Chemie (International ed. in English)》2023,62(32):e202218706
Stimuli-responsive or smart materials have recently shown a significant impact on the frontier of material science and engineering. The exponential development of synthetic host molecules (SHMs) over the last decades and their corresponding host–guest chemistry, have empowered researchers with new opportunities to design and construct tailored or guest-specific smart materials. In this Minireview, we present the recent advancements in synthetic host based smart materials, ranging from the fabrication strategies to the state-of-art applications including adsorption, separation, luminescence, self-healing and actuation. The role that the host–guest chemistry plays in these systems is highlighted throughout to give a better prospective of the available possibilities for emerging materials of future economies. 相似文献
58.
M. A. Niyas Dr. Kazutaka Shoyama Prof. Dr. Frank Würthner 《Angewandte Chemie (International ed. in English)》2023,62(25):e202302032
Phthalocyanines are extensively used by the dye and pigment industry and in photovoltaic and photodynamic therapy research due to their intense absorption of visible light, outstanding stability, and versatility. As pigments, the unsubstituted phthalocyanines are insoluble owing to strong intermolecular π-π-stacking interactions, which causes limitations for the solution chemistry for both free base and metalated phthalocyanines. Here we show a supramolecular host–guest strategy to dissolve phthalocyanines into solution. C64 nanographene tetraimide ( 1 ) binds two free base/zinc/copper phthalocyanines in a 1 : 2 stoichiometry to solubilize phthalocyanines as evidenced by 1H NMR spectroscopy, UV/Vis absorption and single-crystal X-ray analysis. Binding studies using a tetra-tert-butyl-substituted soluble phthalocyanine revealed binding affinities of up to 109 M−1 in tetrachloromethane, relating to a Gibbs free energy of −52 kJ mol−1. Energy decomposition analysis revealed that complexes between 1 and phthalocyanines are stabilized by dispersion interactions followed by electrostatics as well as significant charge-transfer interactions. 相似文献
59.
Prof. Bingbing Shi Xupeng Li Yongping Chai Peng Qin Yi Zhou Dr. Wen-Juan Qu Prof. Qi Lin Prof. Tai-Bao Wei Prof. Yan Sun Prof. Peter J. Stang 《Angewandte Chemie (International ed. in English)》2023,62(31):e202305767
Macrocyclic molecule-based host–guest systems, which provide contributions for the design and construction of functional supramolecular structures, have gained increasing attention in recent years. In particular, platinum(II) metallacycle-based host–guest systems provide opportunities for chemical scientists to prepare novel materials with various functions and structures due to the well-defined shapes and cavity sizes of platinum(II) metallacycles. However, the research on platinum(II) metallacycle-based host–guest systems has been given little attention. In this article, we demonstrate the host–guest complexation between a platinum(II) metallacycle and a polycyclic aromatic hydrocarbon molecule, naphthalene. Taking advantage of metallacycle-based host–guest interactions and the dynamic property of reversible Pt coordination bonds, a [2]rotaxane is efficiently prepared by employing a template-directed clipping procedure. The [2]rotaxane is further applied to the fabrication of an efficient light-harvesting system with multi-step energy transfer process. This work comprises an important supplement to macrocycle-based host–guest systems and demonstrates a strategy for efficient production of well-defined mechanically interlocked molecules with practical values. 相似文献
60.
正杆状病毒是节肢动物特异性的DNA病毒,具有载体容量大、增殖滴度高、易于大量扩增且对脊椎动物无致病性等优点,在新型基因载体及疫苗开发等方面具有广阔的应用前景[1,2].然而,杆状病毒缺乏对脊椎动物细胞的靶向性,因此有必要对杆状病毒进行修饰[3~5].叶酸(FA)是一种人体必需的维生素,具有分子量小、稳定性好、无免疫原性及易于与其它载体或药物键合等优点.由于叶酸受体在多种肿瘤细胞中过度表达,叶酸已成为一种常见的通用型肿瘤靶向分子[6~9].本文采用宿主细胞中磷脂"自 相似文献