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101.
Four infinite complexes X 1 [Ni(NCS) 2 (4,4'-oda) 2 ], X 2 [Co(NCS) 2 (4,4'-oda) 2 ] and X 2 [M(N 3 )(4,4'-oda) 2 ]NO 3 [M=Cd II ( 3 ) or Co II ( 4 )] were obtained by reactions 4,4'-oxydianiline (4,4'-oda) with Ni(SCN) 2 , Co(SCN) 2 , Cd(N 3 ) 2 and Co(N 3 ) 2 , respectively which have been structurally established by single-crystal X-ray diffraction. Complex 1 contains one-dimensional double-stranded chains comprising 24-membered Ni 2 (4,4'-oda) 2 macrocycles, each formed by two 4,4'-oda ligands and two octahedral Ni II centers. Complex 2 exhibits two-dimensional non-interpenetrating networks consisting of large 48-membered macrocycles each formed by four 4,4'-oda ligands and four octahedral Co II centers. The crystal structures of 3 and 4 are isomorphous and both contain one-dimensional double-stranded chains comprising 24-membered M 2 (4,4'-oda) 2 macrocycles, which are interlinked by w -1,3-azide groups to generate cationic two-dimensional sheets. These sheets are further connected by hydrogen bonds between the amine groups and nitrate ions to furnish three-dimensional networks. Crystal data: complex 1 crystallizes in the monoclinic space group P 2 1 / c with a =11.990(4) Å, b =9.413(4) Å, c =12.827(4) Å, g =116.32(2), V =1297.6(8) Å 3 and Z =2; complex 2 crystallizes in the orthorhombic space group Pbca with a =9.583(2) Å, b =12.738(3) Å, c =21.039(4) Å, V =2568.2(9) Å 3 and Z =4; complex 3 crystallizes in the monoclinic space group C 2/ c with a =23.036(5) Å, b =5.920(1) Å, c =17.800(4) Å, g = 92.67(3), V =2424.8(9) Å 3 and Z =4; complex 4 crystallizes in the monoclinic space group C 2/ c with a = 22.861(5) Å, b =5.812(1) Å, c =17.720(4) Å, g =93.00(3), V =2351.2(8) Å 3 and Z =4. 相似文献
102.
T. Fujita 《SAR and QSAR in environmental research》2013,24(1-2):77-88
A series of our SAR and QSAR studies of synthetic moulting hormone agonists, dibenzoylhydrazines (DBH), exhibiting insecticidal/larvicidal activity are reviewed in this article. We prepared a number of analogues where various substituents are introduced into the two benzene rings of DBH and measured their biological activity using various biological systems. Larvicidal activity was against larvae of the rice stem borer Chilo suppressalis and the moulting hormone activity was in terms of the stimulation of N-acetylglucosamine incorporation in a cultured integument system of the same insect species. Binding affinity to the ecdysone receptor was assayed with intact Sf-9 cell lines in which the ADME processes are negligible as well as using receptor proteins obtained by in vitro translation of the responsible cDNA cloned from cell-free preparation of integumentary tissue of C. suppressalis. Variations in the biological activity indices were either correlated between two types of activity or correlated using physicochemical molecular and substituent parameters in terms of the classical QSAR. Comparisons among correlations and with recently revealed X-ray crystallographic findings clearly indicate the physicochemical meaning of parameters significant in the correlation equations to help understanding molecular mechanism of the moulting hormonal action. 相似文献
103.
在水热条件下,以N-氧化-2-吡啶膦酸(H2L)为主配体,4,4'-联吡啶(bpy)为桥联配体,合成了3个铜有机膦酸配合物: {[CuL(bpy)0.5(H2O)]·2H2O}n(1), {[Cu(HL)2(bpy)]·4H2O}n(2)和{[Cu2(L)2(bpy)]·3H2O}n(3)。配合物1中,相邻的铜离子由2个膦酸根连成二聚体,二聚体之间通过bpy桥联成一维链。配合物2中,单核[Cu(HL)2]被bpy连接成一维链。配合物3中,四聚体[Cu2(L)2]2被bpy连接成“砖块状”结构的二维层。磁性研究表明,配合物1和3中铜离子之间存在反铁磁性耦合。 相似文献
104.
使用3,3''-硫代二丙酸、4,4''-联吡啶和硝酸锰在水热条件下反应合成了1个锰配合物,即{[Mn(DPA)(4,4''-bipy)]·H2O}n(1)(DPA=3,3''-硫代二丙酸,4,4''-bipy=4,4''-联吡啶);然后又利用3,3''-硫代二丙酸、1,3-双(4-吡啶基)丙烷和硝酸铜在水热条件下反应合成了1个铜配合物,即{[Cu(DPA)(bpp)(H2O)]·H2O}n(2)(DPA=3,3''-硫代二丙酸,bpp=1,3-双(4-吡啶基)丙烷)。并对它们分别进行了元素分析、红外光谱、热稳定性、X射线粉末衍射和X射线单晶衍射的表征。结果表明:配合物1和2分别由3,3''-硫代二丙酸配体和不同氮杂环分子以及金属离子构筑,形成了二维层状的结构。氢键和π-π作用进一步将二维结构拓展成三维超分子网络。 相似文献
105.
通过水热法合成得到了一个包含四核镉(Ⅱ)的基于2-丙基-4,5-二甲酸咪唑和4,4-联吡啶的配位聚合物[Cd2(HPIDC)2(bpy)(H2O)2](1)。X-射线单晶衍射分析结果表明:配合物1属单斜晶系,结晶在c2/c空间群中,晶胞参数为:a=1.936 6(4)nm,b=1.504 1(3)nm,c=2.200 4(5)nm,β=94.990(4)°,V=6.385(2)nm3,Z=8,1.393 mm-1,F(000)=3 216,Dc=1.684 g.cm-3,R1=0.045 8,wR2=0.108 9。通过链间的O-H…O氢键作用,形成了三维的超分子结构。固体荧光测试表明:配合物1在427 nm处发射出较强的荧光。 相似文献
106.
Self‐assembled monolayers of cucurbit[6]uril (CB[6]) on a gold electrode have been used for 4,4′‐oxydialine (ODA) analysis. The formation of the supramolecular complex between ODA and CB[6] was used for the molecular selection and the electroanalytical determination of this analyte. In addition to this, all the parameters affecting the modification of the gold electrode and the determination of 4,4′‐oxydianiline were optimized by square wave voltammetry. Upon the electrode modification, pentanethiol was employed to fill up the exposed surface between CB[6] molecules. The calculated detection and determination limits were 0.06 µg mL?1 and 0.19 µg mL?1, respectively, with good accuracy and precision as shown by the calculated values for the relative error and relative standard deviation (Er=0.1 % and RDS=2.9 %; n=10 ). Moreover, the developed methodology was successfully applied to the 4,4′‐oxydialine determination in real wastewaters and shoe‐dyeing samples. 相似文献
107.
N‐aroyl‐N′‐arylsulfonylhydrazines can be obtained by oxidation of aromatic aldehyde N‐arylsulfonylhydrazones with bis(trifluoroacetoxy)iodobenzene in acetone at room temperature in mild to good yields. 相似文献
108.
A series of furo[2′,1′:5,6]pyrido[2,3-d]pyrimidine derivatives were synthesized via the three-component reaction of an aldehyde, tetronic acid, and 6-amino-1,3-dimethyl-pyrimidine-2,4-dione in aqueous media without the use of catalyst. This protocol has the advantages of better yields, less cost, reduced environmental impact, and convenient procedure. 相似文献
109.
The reaction of ribonucleoside‐5′‐phosphoroimidazolide with a tributylammonium orthophosphate in anhydrous dimethylformamide at room temperature provides a general method for the synthesis of nucleoside‐5′‐diphosphates. The novelty of the approach is to use the triethylammonium salt of 5′‐monophosphate nucleoside derivative prior to the imidazolate reaction with imidazole, triphenylphosphine, and 2,2′‐dithiodipyridine. Deprotection, followed by displacement of the imidazole moiety using tributylammonium orthophosphate and a catalytic amount of zinc chloride in dimethylformamide gave the desired 5′‐diphosphate products. The triethyl ammonium salt of 5′‐diphosphate nucleosides was purified by flash chromatography using DEAE (diethylaminoethyl weak anion exchange resin) Sepharosa fast flow packed in an XK 50/60 column on an Akta FPLC (Fast Protein Liquid Chromatography). Synthesis procedures are reported for adenosine‐5′‐diphosphate, uridine‐5′‐diphosphate, cytidine‐5′‐diphosphate, and guanosine‐5′‐diphosphate. Yields for the displacement reactions ranged from 95 to 97%. Thus, this method offers the advantages of shorter reaction time, greater product yield, and a more cost‐effective synthetic route. 相似文献
110.
Masanori Miura Takanori Koike Tsukasa Ishihara Fukushi Hirayama Shuichi Sakamoto Minoru Okada 《合成通讯》2013,43(24):3809-3820
A one‐pot synthetic procedure for 2,2′‐disubstituted biaryls was developed via a Suzuki cross‐coupling reaction of aryl triflates in a biphasic solvent system. The effects of various bases and solvents were investigated. Results showed that the Na2CO3–toluene/H2O combination gave the highest yields. 相似文献