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991.
Zhu Kai Li Cui Wu Kingsley Y. Mohr Christopher Li Xun Lanman Brian 《Journal of computer-aided molecular design》2022,36(8):591-604
Journal of Computer-Aided Molecular Design - KRAS has long been referred to as an ‘undruggable’ target due to its high affinity for its cognate ligands (GDP and GTP) and its lack of... 相似文献
992.
993.
Metal‐Free Reaction of ortho‐Carbonylated Alkynyl‐Substituted Arylaldehydes with Common Amines: Selective Access to Functionalized Isoindolinone and Indenamine Derivatives 下载免费PDF全文
Dr. Ziping Cao Hongbo Zhu Dr. Xin Meng Jun Guan Qiang Zhang Laijin Tian Xuejun Sun Guang Chen Prof. Dr. Jinmao You 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16979-16985
Herein we describe a reaction of ortho‐carbonylated alkynyl‐substituted arylaldehydes with common primary amines that can provide functionalized isoindolinone and 3‐hydroxylindenamine products in high yields. Depending on the substituent size of primary amines, two distinct reaction pathways were exploited selectively, that are, an initial aza‐conjugate addition followed by hydrogen transfer to access isoindolinone framework and a unique oxa‐conjugate addition followed by Petasis–Ferrier rearrangement to afford indenamine derivatives. In the presence of Et3N, the reaction property of small primary amines was changed, proceeding to afford 3‐hydroxylindenamine derivatives efficiently. These products contain interesting substructures that exist in many natural products and bioactive molecules. The reaction features contain the use of transition‐metal‐free catalysts, simple operation, broad substrate scope, and product diversity. 相似文献
994.
Generation of Oxazolidine‐2,4‐diones Bearing Sulfur‐Substituted Quaternary Carbon Atoms by Oxothiolation/Cyclization of Ynamides 下载免费PDF全文
Hai Huang Junzhen Fan Dr. Guangke He Zhimin Yang Xiaodong Jin Qi Liu Prof. Dr. Hongjun Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2532-2538
A novel method for metal‐free oxothiolation of ynamides to construct oxazolidine‐2,4‐diones bearing sulfur‐substituted quaternary carbon atoms has been developed. It represents a rare C?O bond cleavage of ynamides, as well as a facile and tandem approach for the formation of C?O, C?S, and C?Cl bonds. This redox‐neutral protocol can be applied to the synthesis of multisubstituted oxazolidine‐2,4‐diones with good chemoselectivity and good yields of isolated products under mild conditions. 相似文献
995.
996.
Nickel-cobalt layered double hydroxides (NiCo-LDH) were successfully deposited on nickel foam by a facile hydrothermal method using polyvinyl pyrrolidone (PVP) as the structure-directing reagent. The effect of PVP on the morphology and electrochemical performance of binder-free NiCo-LDH electrode for supercapacitor were investigated in detail. The prepared NiCo-LDH presented good dispersivity and appeared different flower-like structure via the addition of PVP. Specially, the NiCo-LDH electrode using 1 g of PVP exhibited a superior performance with a high-specific capacity of 724.9 C g?1 at a current density of 1 A g?1 and 577.1 C g?1 at 10 A g?1. In addition, a hybrid supercapacitor (HSC) based on the optimized NiCo-LDH as positive electrode and activated carbon as negative electrode was assembled with 6 M KOH as the electrolyte. The HSC device can deliver an energy density of 32.3 Wh kg?1 at the power density of 387.1 W kg?1. Moreover, the HSC device exhibited a good cycling stability with a retention rate of 94.0% after 2000-cycle charge-discharge test at 3 A g?1. 相似文献
997.
Cui‐Wei Wang Chao Liu Xiao‐Wei Zhu Zi‐Ying Yang Hong‐Fan Sun De‐Ling Kong Jing Yang 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):407-417
Well‐defined star‐shaped hydrophobic poly(ε‐caprolactone) (PCL) and hydrophilic poly(ethylene glycol) (PEG) amphiphilic conetworks (APCNs) have been synthesized via the combination of ring opening polymerization (ROP) and click chemistry. Alkyne‐terminated six arm star‐shaped PCL (6‐s‐PCLx‐C?CH) and azido‐terminated PEG (N3‐PEG‐N3) are characterized by 1H NMR and FT‐IR. The swelling degree of the APCNs is determined both in water and organic solvent. This unique property of the conetworks is dependent on the nanophase separation of hydrophilic and hydrophobic phases. The morphology and thermal behaviors of the APCNs are investigated by SEM and DSC respectively. The biocompatibility is determined by water soluble tetrazolium salt reagents (WST‐1) assay, which shows the new polymer networks had good biocompatibility. Through in vitro release of paclitaxel (PTX) and doxorubicin (DOX), the APCNs is confirmed to be promising drug depot materials for sustained hydrophobic and hydrophilic drugs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 407–417 相似文献
998.
Dithienoindophenines: p‐Type Semiconductors Designed by Quinoid Stabilization for Solar‐Cell Applications 下载免费PDF全文
Longbin Ren Dr. Haijun Fan Dazhen Huang Dafei Yuan Prof. Dr. Chong‐an Di Prof. Dr. Xiaozhang Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17136-17140
Compared with the dominant aromatic conjugated materials, photovoltaic applications of their quinoidal counterparts featuring rigid and planar molecular structures have long been unexplored despite their narrow optical bandgaps, large absorption coefficients, and excellent charge‐transport properties. The design and synthesis of dithienoindophenine derivatives (DTIPs) by stabilizing the quinoidal resonance of the parent indophenine framework is reported here. Compared with the ambipolar indophenine derivatives, DTIPs with the fixed molecular configuration are found to be p‐type semiconductors exhibiting excellent unipolar hole mobilities up to 0.22 cm2 V?1 s?1, which is one order of magnitude higher than that of the parent IP‐O and is even comparable to that of QQT(CN)4‐based single‐crystal field‐effect transistors (FET). DTIPs exhibit better photovoltaic performance than their aromatic bithieno[3,4‐b]thiophene (BTT) counterparts with an optimal power‐conversion efficiency (PCE) of 4.07 %. 相似文献
999.
1000.
We present a review of photoexcited quasiparticle dynamics of cuprate and pnictide high‐temperature superconductors in regimes (temperature, doping) where different phases such as superconductivity, spin‐density‐wave (SDW) and pseudogap phases coexist or compete with one another. We start with the overdoped cuprate superconductor Y1–xCax Ba2Cu3O7–δ, where the superconducting gap and pseudogap coexist in the superconducting state. In another cuprate Tl2Ba2Ca2Cu3Oy, we ob‐ serve a competition between SDW and superconducting orders deep in the superconducting state. Finally, in the underdoped iron pnictide superconductor (Ba,K)Fe2As2, SDW order forms at 85 K, followed by superconductivity at 28 K. We also find the emergence of a normal‐state order that suppresses SDW at a temperature T * ~ 60 K and argue that this normal‐state order is a precursor to superconductivity. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献