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991.
992.
Three new cobalt complexes were synthesized by solid-state reaction at room temperature. It was found that one mole of complex reacted with two moles of oxygen at room temperature. And the oxygenated complexes [Co·(L1)2·2O2](NO3)2·2H2O (L1=N,N′-bis(4-hydroxyl-3-methoxy-benzyl)-triethylenetetramine), [Co·(L2)2·2O2](NO3)2 ·2H2O (L2=N,N′-bis(4-hydroxyl-benzyl)-triethylenetetramine) and [Co·L3·2O2](NO3)2·2H2O (L3=N,N′-bis(2-hydroxyl-benzyl)-triethylenetetramine) were obtained and characterized by elemental analysis, IR spectra, 1H NMR, TG/DTA, UV-Vis and molar conductance. The coordinated oxygen contents in the oxygenated complex were also determined by weight method. It was found that one O2 molecule coordinated to the Co ion and formed superoxo type oxygenated complex. 相似文献
993.
The EPR spectra of three new gadolinium complexes with noncyclic polyether Schiff bases in powder and those of these complexes in organic solvents were investigated at different temperatures. It was observed that EPR spectra of nine and four peaks of Gd(Ⅲ) complexes in polycrystalline powder and freezing samples appeared at low temperature respectively for the first time. The interpretations of these results obtained on the basis of spin Hamiltonian of s = 7/2 system are satisfactory. The correlations of EPR feature between crystal-field strength in complexes and local symmetry around Gd3+ ions were revealed. The crystal-field parameters b20 and the asymmetry parameters λ' of complexes were estimated. A series of interesting regularity and new results were obtained. 相似文献
994.
995.
996.
3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮的合成与晶体结构 总被引:3,自引:0,他引:3
合成了3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮.通过元素分析、红外光谱、紫外光谱、核磁共振氢谱和质谱对其组成和结构进行了表征.利用X射线衍射分析方法测定了它的晶体结构.该化合物的晶体属单斜晶系,空间群P21/c,a=1.41946(17)nm,b=0.58445(7)nm,c=2.1756(3)nm,β=104.795(2)°,V=1.7450(4)nm3,Z=4,Dc=1.280 g·cm-3,F(000)=712,μ=0.088mm-1,R1[I>2σ(I)]=0.0627,wR2[I>2σ(I)]=0.1484.晶体结构测定结果表明化合物分子中的环己烯部分为半椅式构象,分子间通过氢键形成具有16元环的二聚体. 相似文献
997.
998.
Xiao Ying Xu Feng Cheng Jian Hua Shen Xiao Min Luo Li Li Chen Li Duo Yue Yi Du Fei Ye Shan Hao Jiang Da Yuan Zhu Hua Liang Jiang Kai Xian Chen 《International journal of quantum chemistry》2003,93(6):405-410
Docking simulation of 18 agonists with the ligand binding pocket (LBP) of PPARγ has been performed. The binding conformations and binding affinities of these agonists were obtained by use of the flexible docking protocol FlexX. Test compound calculations indicated that FlexX can reproduce the binding conformation of the crystal structure (root mean square deviation = 1.43 Å); moreover, the predicted binding affinities correlate well with the activities of these agonists. The interaction model and pharmacophore of PPARγ agonists were derived and the difference in biologic activities of these agonists can be well explained. The PPARγ agonists must have both polar head and the hydrophobic tail, which form hydrogen bonds and hydrophobic contacts with hydrophilic and hydrophobic regions of the LBP of PPARγ, respectively. In addition, a suitable linker is also necessary. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 405–410, 2003 相似文献
999.
具有超大通道结构的介孔氧化硅柱层状钛酸的合成和催化应用初探 总被引:6,自引:0,他引:6
A mesoporous (d=2.3mm) silica-pillared layered tetratitanate with a super gallery (d001=1.84mm)was prepared by first preswelling layered tetratitanate with n-dodecyl amine, then reacting with 20wt% NH2(CH2)3Si(OC2H5)3 aqueous solution, and finally calcinating the resultant solid product in air at 550℃. All the reaction was carried out hydrothermally in an autoclave at 130℃. The obtained material has a relatively high BET surface area of 204m2·g-1 and a thermal stability beyond 600℃. The catalytic application of the material was also investigated by using the dehydration of isopropanol and the reform of n-hexane as two probing reactions. 相似文献
1000.