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931.
Qian Wu 《Tetrahedron letters》2010,51(37):4806-4807
A simple and five steps total synthesis of Ammosamide B has been developed. The tricyclic pyrroloquinoline in Ammosamides was constructed in one step based on Doebner-Miller reaction between 1,3-diamine-4,6-dinitrobenzene 8 and dimethyl-2-oxo glutaconate 9. 相似文献
932.
Reactions of triguanidinate lanthanide complexes Ln[(iPrN)(NC6H4p-Cl)C(NHiPr)]3 (Ln = Nd, Y) with 3 equiv. of n-BuLi gave [Li(THF)(DME)]3Ln[μ-η2η1 (iPrN)2C(NC6H4p-Cl)]3, which represents the first structurally characterized complexes of lanthanide and lithium metals with dianionic guanidinate ligands. The Nd complex was found to be an effective catalyst for amidation of aldehydes with amines under mild conditions with a wide scope of substrates. 相似文献
933.
Zhongyue Zhou Mingfeng Xie Tang Tang Yijun Zhang Tao Yuan Fei Qi Tom Ni Xueyu Qian 《Plasma Chemistry and Plasma Processing》2010,30(3):391-400
Capacitive radio frequency (RF) discharge of c-C4F8 (octafluorocyclobutane) has been studied with synchrotron vacuum ultraviolet (SVUV) photoionization mass spectrometry (PIMS)
at 4 Torr and 33.33 kHz. Various free radicals and reactive intermediates have been identified through measurement of photoionization
mass spectra and photoionization efficiency (PIE) spectra. CF2=CF2 is main product in the plasma, indicating that the dissociation of c-C4F8 into CF2=CF2 is one of prominent reactions in the present experimental conditions. The observation of large species including C5F8, C5F10 and C6F10 is presented in our work. Besides, the dependences of the signals of neutral species in the discharge of c-C4F8 on RF power are presented in this paper. 相似文献
934.
In this paper, two novel kinds of organic–inorganic monomer, SUA-APEMS and SUA-APS, have been achieved by modifying 5-sulfosalicylic acid (SUA) with 3-aminopropyl-methyl-diethoxylsilane (APEMS) and 3-aminopropyl trimethoxysilane (APS). These two organic–inorganic monomers were used as multi-functional bridged components, which can coordinate to metal ions (Tb3+/Eu3+/Zn2+) with carbonyl groups, strongly absorb ultraviolet and effectively transfer energy to metal ions through their triplet excited state, as well as involve in the sol–gel process with inorganic host precursor tetraethoxysilane (TEOS), resulting two series of molecular hybrid materials (named as SUA-APEMS/APS-RE) with double chemical bond (RE(Zn)–O coordination bond and Si–O covalent bond). The effective intra-molecular energy transfer process gives rise to the characteristic emission of metal ions and the chemical bond make the hybrid materials owning better properties. 相似文献
935.
Miaojing Chen Hong Li Qian Li Zhenghe Xu 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(5):1566-1570
The luminescence properties of [Ru(bpy)2MDHIP]2+ (bpy = 2,2′-bipyridine, MDHIP = 2,4-dihydrophenyl-imidazo[4,5-f][1,10]phenanthroline) in the absence and presence of DNA modulated by the introduction of Cu2+ ion and EDTA have been investigated. It is found that the ruthenium(II) complex can insert and stack between the base pairs of calf thymus DNA with MDHIP ligand, and the intramolecular hydrogen bond is located inside of the DNA. The presence of DNA can enhance the luminescence intensities of [Ru(bpy)2MDHIP]2+ both in buffer solution and on an ITO surface. Moreover, the luminescence intensities of [Ru(bpy)2MDHIP]2+ and DNA-bound [Ru(bpy)2MDHIP]2+ are quenched by Cu2+, and next recovered by the addition of EDTA. The repetitive luminescence-modulations have been achieved through the introduction of equimolar Cu2+ and EDTA, respectively. In addition, it becomes evident that the number of luminescence-modulation cycles for [Ru(bpy)2MDHIP]2+ in the absence and presence of DNA is influenced by the cumulative concentrations of CuEDTA, generated successively by the strong coordination of Cu2+ to EDTA. 相似文献
936.
Hu BW Zhao JP Yang Q Zhang XF Evangelisti M Sañudo EC Bu XH 《Dalton transactions (Cambridge, England : 2003)》2010,39(46):11210-11217
Two new azido-Co(II) complexes with pyrazine carboxylato ligands, [Co(N(3))(L)·H(2)O](n) (L = pyrazine-2-carboxylato) (1) and [CoNa(N(3))(2)(L)](n) (2), have been obtained by carefully tuning the Co(II):N(3)(-) ratio. Here we present the structural and magnetic characterization of these new species. Modulation of the coordination environment of Co(II) leads to a variation of the magnetic properties of the obtained compounds. Complex 1 exhibits ferromagnetically coupled [Co(2)] units that form the rungs of the ladder with a nearly negligible coupling between these units, while complex 2 is a 2D arrangement of 1D Co(II) single-chain magnets. 相似文献
937.
Jun Gu Yongchun Zhu Haibo Li Shenglin Xiong Xianwen Zhang Xiaoqing Wang Xiaoyan Liu Yitai Qian 《Solid State Sciences》2010,12(7):1192-1198
NaLa(WO4)2:Eu microcrystals with shapes of four-arris shuttle, quadrangled star, and quadrangled dendrite were hydrothermally synthesized at 180 °C for 16 h. The concentration of the reactants and cetyltrimethyl ammonium bromide (CTAB) influenced the morphologies of the products. As La(NO3)3, Na2WO4 and CTAB was 0.375, 1.0, and 1.0 mmol, respectively, four-arris shuttle was obtained. As the concentration of the reactants doubled and the amount of CTAB ranged from 0.4 to 2.0 mmol, quadrangled dendrite, quadrangled star and four-arris shuttle were prepared, respectively. Luminescence intensity measurement of the three morphologies of NaLa(WO4)2:Eu showed that quadrangled dendrite was the strongest and four-arris shuttle was the lowest. 相似文献
938.
ChengLian Feng YiPing Xu JinMiao Zha Qian Luo XiaoQuan Shan ZiJian Wang 《中国科学:化学(英文版)》2010,53(11):2379-2386
Decabromodiphenyl ether (BDE209) is poorly absorbed by mammals, and little information is available on the toxicokinetics of BDE209 and its metabolites in fish. In the present study, rainbow trout (Oncorhynchus mykiss) were administered to 100 ng/g and 500 ng/g body wet weight of BDE209 via a single intraperitoneal injection and parent BDE209 and its metabolites were sequentially monitored for 28 days. The results showed that toxicokinetic profiles of BDE209 could be described by the one-compartment model. In the higher dose group (500 ng/g wet weight), the calculated half-life (t 1/2) and elimination rate (k e) were 17.7 d and 0.039/d in the liver, and 100.3 d and 0.007/d in the muscle, respectively. Three major methoxylated brominated diphenyl ethers (MeO-BDEs) were detected with 2,2′,4,4′-tetrabromo-5-methoxydiphenyl ether (5-MeO-BDE47) being detected in all tissue samples. There was no significant temporal change of 5-MeO-BDE47 concentration in the muscle, whereas an exponential increase was observed in the liver. Therefore, the metabolism rate of BDE209 depended on the administered dose. BDE209 was hardly accumulated in the muscle of rainbow trout, while the liver was a primary metabolic organ. MeO-BDEs were formed via metabolism of BDE209, which probably played a significant role in fish toxicology as a potential indicator. 相似文献
939.
Thomas J. Payne Chad R. Thurman Hao Yu Qian Sun Dillip K. Mohanty Philip J. Squattrito Mark‐Robin Giolando Christopher R. Brue Kristin Kirschbaum 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(7):o369-o373
N,N′‐Diethyl‐4‐nitrobenzene‐1,3‐diamine, C10H15N3O2, (I), crystallizes with two independent molecules in the asymmetric unit, both of which are nearly planar. The molecules differ in the conformation of the ethylamine group trans to the nitro group. Both molecules contain intramolecular N—H...O hydrogen bonds between the adjacent amine and nitro groups and are linked into one‐dimensional chains by intermolecular N—H...O hydrogen bonds. The chains are organized in layers parallel to (101) with separations of ca 3.4 Å between adjacent sheets. The packing is quite different from what was observed in isomeric 1,3‐bis(ethylamino)‐2‐nitrobenzene. 2,6‐Bis(ethylamino)‐3‐nitrobenzonitrile, C11H14N4O2, (II), differs from (I) only in the presence of the nitrile functionality between the two ethylamine groups. Compound (II) crystallizes with one unique molecule in the asymmetric unit. In contrast with (I), one of the ethylamine groups, which is disordered over two sites with occupancies of 0.75 and 0.25, is positioned so that the methyl group is directed out of the plane of the ring by approximately 85°. This ethylamine group forms an intramolecular N—H...O hydrogen bond with the adjacent nitro group. The packing in (II) is very different from that in (I). Molecules of (II) are linked by both intermolecular amine–nitro N—H...O and amine–nitrile N—H...N hydrogen bonds into a two‐dimensional network in the (10) plane. Alternating molecules are approximately orthogonal to one another, indicating that π–π interactions are not a significant factor in the packing. Bis(4‐ethylamino‐3‐nitrophenyl) sulfone, C16H18N4O6S, (III), contains the same ortho nitro/ethylamine pairing as in (I), with the position para to the nitro group occupied by the sulfone instead of a second ethylamine group. Each 4‐ethylamino‐3‐nitrobenzene moiety is nearly planar and contains the typical intramolecular N—H...O hydrogen bond. Due to the tetrahedral geometry about the S atom, the molecules of (III) adopt an overall V shape. There are no intermolecular amine–nitro hydrogen bonds. Rather, each amine H atom has a long (H...O ca 2.8 Å) interaction with one of the sulfone O atoms. Molecules of (III) are thus linked by amine–sulfone N—H...O hydrogen bonds into zigzag double chains running along [001]. Taken together, these structures demonstrate that small changes in the functionalization of ethylamine–nitroarenes cause significant differences in the intermolecular interactions and packing. 相似文献
940.
Yu‐Bo Wang Tong‐Hen Pan Qian Liang Dong‐Sheng Liu Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(5):m127-m129
The asymmetric unit of the title complex, [CdCl2(C14H12N4O2S)2]n, consists of one CdII ion located on the crystallographic inversion centre, one 4‐benzoyl‐1‐isonicotinoylthiosemicarbazide ligand and one chloride ligand. The central CdII ion adopts a distorted octahedral coordination geometry formed by two pyridyl N atoms of two ligands, two S atoms of two other ligands and two chloride ligands. The thiosemicarbazide ligands act as bridges, linking the metal ions into a two‐dimensional layered structure parallel to the bc plane. Intermolecular N—H...O hydrogen bonds and C—H...π interactions exist between adjacent layers. 相似文献