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121.
Tie‐Gen Chen Haolin Zhang Pavel K. Mykhailiuk Rohan R. Merchant Courtney A. Smith Tian Qin Phil S. Baran 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2476-2480
This work bridges a gap in the cross‐coupling of aliphatic redox‐active esters with aryl zinc reagents. Previously limited to primary, secondary, and specialized tertiary centers, a new protocol has been devised to enable the coupling of general tertiary systems using nickel catalysis. The scope of this operationally simple method is broad, and it can be used to simplify the synthesis of medicinally relevant motifs bearing quaternary centers. 相似文献
122.
Ying‐Ming Zhang Jiang‐Hua Liu Qilin Yu Xin Wen Yu Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10663-10667
Tunable protein assemblies not only hold a dominant position in vital biological events but are also a significant theme in supramolecular chemistry. Herein, we demonstrated that the intertubular aggregation of microtubules (MTs) could be efficiently regulated by a synergistic polypeptide–tubulin interaction and host–guest complexation. The benzylimidazolium‐modified antimitotic peptide (BP) could recognize the MTs and concurrently form stable inclusion complexes with avirulent cucurbit[7]uril (CB[7]) and cucurbit[8]uril (CB[8]) in different binding stoichiometries. The self‐assembling morphology of MTs was converted from fibrous to nanoparticulate aggregates via extensive BP?CB[8] cross‐linkage, leading to significant cell apoptosis and tumor ablation in vivo. The targeted (BP?CB[8])@MT ternary assembly provides a facile supramolecular method to enhance the protein–protein interactions, which may be developed as a therapy for degenerative diseases, such as cancer. 相似文献
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Junrui Li Safia Z. Jilani Honghong Lin Xiaoming Liu Kecheng Wei Yukai Jia Peng Zhang Miaofang Chi YuYe J. Tong Zheng Xi Shouheng Sun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(33):11651-11657
Efficient electro‐oxidation of formic acid, methanol, and ethanol is challenging owing to the multiple chemical reaction steps required to accomplish full oxidation to CO2. Herein, a ternary CoPtAu nanoparticle catalyst system is reported in which Co and Pt form an intermetallic L10‐structure and Au segregates on the surface to alloy with Pt. The L10‐structure stabilizes Co and significantly enhances the catalysis of the PtAu surface towards electro‐oxidation of ethanol, methanol, and formic acid, with mass activities of 1.55 A/mgPt, 1.49 A/mgPt, and 11.97 A/mgPt, respectively in 0.1 m HClO4. The L10‐CoPtAu catalyst is also stable, with negligible degradation in mass activities and no obvious Co/Pt/Au composition changes after 10 000 potential cycles. The in situ surface‐enhanced infrared absorption spectroscopy study indicates that the ternary catalyst activates the C?C bond more efficiently for ethanol oxidation. 相似文献
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This paper is concerned with the boundary behavior of strictly convex large solutions to the Monge-Ampère equation detD2u(x)=b(x)f(u(x)), u > 0, x ∈ Ω, where Ω is a strictly convex and bounded smooth domain in RN with N ≥ 2, f is normalized regularly varying at infinity with the critical index N and has a lower term, and b ∈ C∞(Ω) is positive in Ω, but may be appropriate singular on the boundary. 相似文献
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The aim of this paper is to present a general convexification recipe that can be useful for studying non-convex variational problems. In particular, this allows us to treat such problems by using a powerful primal–dual scheme. Possible further developments and open issues are given. 相似文献