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131.
An efficient and general route for the synthesis of functionalized hexahydroindole and hexahydrobenzofuran derivatives has been developed via the palladium-catalyzed domino coupling/cyclization reaction of 1,6-enynes and aryl halides. The results indicated that the electronic properties of the aryl halides strongly affect the reaction yields. 相似文献
132.
本文评述了当前细胞无机化学研究中的几个方面,主要是包括钙离子和稀土离子在内的金属离子和活性小分子对细胞膜离子通道、膜受体蛋白、胞内受体蛋白以及对细胞功能的影响. 相似文献
133.
134.
Summary [MoCu3S3Br(SCH2CH2S)(PPh3)3]·MeCN, MW=1382.78, space group Pl, has the triclinic cell parametersa=12.272(11),b=13.172(7),c=20.363(3)Å, =106.26(3)o, =95.64(5)o, =65.79(6)o; Z=2, V=2881.4Å3. Dc=1.55 g cm–3. MoK radiation. =0.71073Å, =22.8 cm–1. F(000)=1348. R=0.69 for 4964 observed unique reflections [I>3(I)]. There are some distortions in the cubane-like MoCu3S3Br core, with three form Mo–Cu bonds. The Mo atom is bound by chelating SCH2CH2S and three 3-S atoms. 相似文献
135.
The effects of La3+ on inward K+ channels at plasma membrane in vicia guard cells are investigated using the whole-cell patch-clamp recording mode. It is
shown that La3+ on both sides of plasma membrane blocks inward K+ currents in a concentration-dependent manner, indicating that La3+ binding sites may exist on both sides of plasma membrane in guard cells in vicia. The dose response is fitted by the Michaelis-Menten
relation characterized by an inhibitor constant K
i
of 2.56±0.25 μmol · L−1 (outside membrane) and (1.18±0.11)×10−15 mol · L−1 (inside membrane). Intracellular La3+ has much stronger inhibitory effect on inward K+ currents than extracellular La3+ does, suggesting there may exist stronger binding sites inside membrane than outside membrane. Since ion channel activities
of guard cells directly affect plant stomatal movement and water status, our results imply that rare earth elements might
have potential practical values in regulating plant water status and strengthening plant drought endurance. 相似文献
136.
Jun Du Zeming Huang Yanan Zhang Prof. Dr. Shaowu Wang Prof. Dr. Shuangliu Zhou Prof. Dr. Huayi Fang Prof. Dr. Peng Cui 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(43):10149-10155
The first heterobimetallic Pd−Sc complex featuring a very short Pd→Sc dative bond has been synthesized and characterized by multinuclear NMR spectroscopy, X-ray diffraction analysis, and electrochemistry. Computational studies elucidated the nature of the Pd→Sc bond as a donor–acceptor interaction, which generates a more electron-deficient Pd0 metal center as compared to that in the mono Pd0 complex in their reactions with isonitrile and carbon monoxide. Cooperative reactivity has been demonstrated in the reaction with MeI. 相似文献
137.
Jun Du Shuangliu Zhou Xiuli Zhang Lijun Zhang Peng Cui Zeming Huang Yun Wei Xiancui Zhu Shaowu Wang 《应用有机金属化学》2020,34(1):e5275
Reactions of the ligand precursors 2-(2′-pyridyl)-3,5-Me2-pyrrole ( L 1 H) and 2-(2-pyridyl)-3,4,5-Me3-pyrrole ( L 2 H) with [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 in toluene afforded a series of low-coordinated rare-earth metal bis-amido complexes L 1 RE[N(SiMe3)2]2 [RE = Y ( 1a ), Dy ( 1b ), Er ( 1c ), Yb ( 1d )] and L 2 RE[N(SiMe3)2]2 [RE = Y ( 2a ), Dy ( 2b ), Er ( 2c ), Yb ( 2d )]. With the ionic radius of rare-earth metal increasing, the reaction of L 1 H and [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 gave dinuclear complexes ( L 1 )2RE(μ-Cl)(μ-η5:η1:η1- L 1 )RE( L 1 )[N(SiMe3)2]2 [RE = Sm ( 1e ), Pr ( 1f )]; however, the reaction of L 2 H and [(Me3Si)2N]3Sm(μ-Cl)Li(THF)3 afforded ( L 2 )2Sm[N(SiMe3)2]2 ( 2e ). Results indicated that the ionic radius of rare-earth metal and subtle change in the ligands have substantial effects on the structure and bonding mode of complexes. The complexes showed a high catalytic activity for the ring-opening reaction of cyclohexene oxide with amines to afford various β-aminoalcohols under mild solvent-free conditions. 相似文献
138.
本文给出了有限交换局部环R上无限线性群GL(R)=∪nGLnR的Sylowp-子群的形式.令M是有限交换局部环R的唯一极大理想,k=R/M为R的剩余类域.用X(k)表示k的特征,并假定P与x(k)互素.作者证明了:GL(R)的任一Sylowp-子群S或者同构于的可数无限直积与P(j)的无限直积的直积(当P≠2或P=2,X(k)β≡1(mod4))或者同构于Pi的无限直积与P(j)的无限直积的直积(当P=2,X(k)β≡3(mod4)),这里,只是GL(epi)R(分别地,GL(2ri)R)的Sylowp-子群,P(j))同构于P=∪i∈Ipi,I是可数集. 相似文献
139.
140.
关于具有终对象的范畴的一些结论 总被引:1,自引:1,他引:0
本文对于具有终对象的范畴的一些结论进行了讨论,诸如在满足公理(P)和公理(U)的条件下的一些结果;另外,关于象与逆象的一些命题也进行了论证. 相似文献