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181.
Hongyu Zhang Changlong Hao Aihua Qu Maozhong Sun Liguang Xu Chuanlai Xu Hua Kuang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7197-7204
The accumulation and deposition of β-amyloid (Aβ) plaques in the brain is considered a potential pathogenic mechanism underlying Alzheimer's disease (AD). Chiral l/d -FexCuySe nanoparticles (NPs) were fabricated that interfer with the self-assembly of Aβ42 monomers and trigger the Aβ42 fibrils in dense structures to become looser monomers under 808 nm near-infrared (NIR) illumination. d -FexCuySe NPs have a much higher affinity for Aβ42 fibrils than l -FexCuySe NPs and chiral Cu2−xSe NPs. The chiral FexCuySe NPs also generate more reactive oxygen species (ROS) than chiral Cu2−xSe NPs under NIR-light irradiation. In living MN9D cells, d -NPs attenuate the adhesion of Aβ42 to membranes and neuron loss after NIR treatment within 10 min without the photothermal effect. In-vivo experiments showed that d -FexCuySe NPs provide an efficient protection against neuronal damage induced by the deposition of Aβ42 and alleviate symptoms in a mouse model of AD, leading to the recovery of cognitive competence. 相似文献
182.
Feng-Xing Li Shu-Jian Ren Pei-Fang Li Peng Yang Prof. Jin Qu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18631-18636
The rapid synthesis of marine ladder polyethers from polyepoxide precursors (in analogy with the biosynthetic pathway hypothesized by Nakanishi) is hampered by the fact that the exo-selective epoxide-opening cyclization cascade that gives THF-type polyethers is preferred over the endo-selective cascade that gives the desired products. We found that perfluoro-tert-butanol (PFTB) cooperating with 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4) can promote endo-selective epoxide-opening cyclization reactions of trisubstituted epoxy alcohols. Starting from readily accessible homochiral polyepoxy alcohols with a methyl group at all the endo-cyclization sites, we were able to construct polyethers up to five consecutive fused 6-, 7-, and/or 8-membered rings in one step. Notably, molecules with the 7/7/6/6 and 7/7/6/7/6 polyether frameworks of hemibrevetoxin B and brevenal, respectively, could be synthesized in 40 % and 17 % chemical yields. 相似文献
183.
Yifan Xie Ning Qu Shaobin Lin Haojun Jiang Yanyan Zhang Xiuqing Zhang Hao Liang Fang Chen Xueling Ou 《Electrophoresis》2020,41(12):1095-1102
SNPs, combined with massively parallel sequencing technology, have proven applicability in noninvasive prenatal paternity testing (NIPPT) for singleton pregnancies in our previous research, using circulating cell-free DNA in maternal plasma. However, the feasibility of NIPPT in twin pregnancies has remained uncertain. As a pilot study, we developed a practical method to noninvasively determine the paternity of twin pregnancies by maternal plasma DNA sequencing based on a massively parallel sequencing platform. Blood samples were collected from 15 pregnant women (twin pregnancies at 9–18 weeks of gestation). Parental DNA and maternal plasma cell-free DNA were analyzed with custom-designed probes covering 5226 polymorphic SNP loci. A mathematical model for data interpretation was established, including the zygosity determination and paternity index calculations. Each plasma sample was independently tested against the alleged father and 90 unrelated males. As a result, the zygosity in each twin case was correctly determined, prior to paternity analysis. Further, the correct biological father was successfully identified, and the paternity of all 90 unrelated males was excluded in each case. Our study demonstrates that NIPPT can be performed for twin pregnancies. This finding may contribute to development in NIPPT and diagnosis of certain genetic diseases. 相似文献
184.
Yuanxin Deng Qi Zhang Prof. Ben L. Feringa Prof. He Tian Prof. Da-Hui Qu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5316-5321
Supramolecular polymers that can heal themselves automatically usually exhibit weakness in mechanical toughness and stretchability. Here we exploit a toughening strategy for a dynamic dry supramolecular network by introducing ionic cluster-enhanced iron-carboxylate complexes. The resulting dry supramolecular network simultaneous exhibits tough mechanical strength, high stretchability, self-healing ability, and processability at room temperature. The excellent performance of these distinct supramolecular polymers is attributed to the hierarchical existence of four types of dynamic combinations in the high-density dry network, including dynamic covalent disulfide bonds, noncovalent H-bonds, iron-carboxylate complexes and ionic clustering interactions. The extremely facile preparation method of this self-healing polymer offers prospects for high-performance low-cost material among others for coatings and wearable devices. 相似文献
185.
Wang Cong Wu Yancong Qu Yao Zhao Kun Xu Jianhua Xia Xinzhao Wu Huilu 《Transition Metal Chemistry》2020,45(8):523-529
Three new metal complexes, namely: [Mn(AIDB)Cl2]·DMF (1), [Zn(AIDB)Br2]·CH3OH (2) and [Co(AIDB)Cl2]·CH3OH (3) having a ligand bis(benzimidazol-2-ylmethyl)allylamine (AIDB), have been synthesized in high yields and characterized by elemental analyses, molar conductivities, IR, UV–Vis spectra and single-crystal X-ray diffraction. The structural analysis revealed that all the three complexes 1–3 have five-coordinated trigonal bipyramid geometry where the degree of distorting is 1>3>2. In vitro antioxidant activity assay demonstrates that the complexes 1 and 3 display high scavenging activity against hydroxyl (OH·) and superoxide (O2−·) radicals.
相似文献186.
Xiaobo Qu Yihui Huang Hengfa Lu Tianyu Qiu Di Guo Tatiana Agback Vladislav Orekhov Zhong Chen 《Angewandte Chemie (International ed. in English)》2020,59(26):10297-10300
Nuclear magnetic resonance (NMR) spectroscopy serves as an indispensable tool in chemistry and biology but often suffers from long experimental times. We present a proof‐of‐concept of the application of deep learning and neural networks for high‐quality, reliable, and very fast NMR spectra reconstruction from limited experimental data. We show that the neural network training can be achieved using solely synthetic NMR signals, which lifts the prohibiting demand for a large volume of realistic training data usually required for a deep learning approach. 相似文献
187.
Liangliang Liang Wei Yan Xian Qin Xiao Peng Han Feng Yu Wang Ziyu Zhu Lingmei Liu Yu Han Qinghua Xu Junle Qu Xiaogang Liu 《Angewandte Chemie (International ed. in English)》2020,59(2):746-751
Stimulated emission depletion (STED) microscopy enables ultrastructural imaging of biological samples with high spatiotemporal resolution. STED nanoprobes based on fluorescent organosilica nanohybrids featuring sub‐2 nm size and near‐unity quantum yield are presented. The spin–orbit coupling (SOC) of heavy‐atom‐rich organic fluorophores is mitigated through a silane‐molecule‐mediated condensation/dehalogenation process, resulting in bright fluorescent organosilica nanohybrids with multiple emitters in one hybrid nanodot. When harnessed as STED nanoprobes, these fluorescent nanohybrids show intense photoluminescence, high biocompatibility, and long‐term photostability. Taking advantage of the low‐power excitation (0.5 μW), prolonged singlet‐state lifetime, and negligible depletion‐induced re‐excitation, these STED nanohybrids present high depletion efficiency (>96 %), extremely low saturation intensity (0.54 mW, ca. 0.188 MW cm?2), and ultra‐high lateral resolution (ca. λem/28). 相似文献
188.
Jie Li Shuanglin Qu Wanxiang Zhao 《Angewandte Chemie (International ed. in English)》2020,59(6):2360-2364
A rhodium‐catalyzed remote C(sp3)?H borylation of silyl enol ethers (SEEs, E/Z mixtures) by alkene isomerization and hydroboration is reported. The reaction exhibits mild reaction conditions and excellent functional‐group tolerance. This method is compatible with an array of SEEs, including linear and branched SEEs derived from aldehydes and ketones, and provides direct access to a broad range of structurally diverse 1,n‐borylethers in excellent regioselectivities and good yields. These compounds are precursors to various valuable chemicals, such as 1,n‐diols and aminoalcohols. 相似文献
189.
Shufang Ji Yang Qu Tao Wang Yuanjun Chen Guofeng Wang Xue Li Juncai Dong QiuYu Chen Wanying Zhang Zedong Zhang Shiyou Liang Rong Yu Yu Wang Dingsheng Wang Yadong Li 《Angewandte Chemie (International ed. in English)》2020,59(26):10651-10657
The solar‐driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN‐NT) with a tunable dispersion density of single atoms. Er1/CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR. 相似文献