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1.
1 INTRODUCTION Benzimidazole is an interesting heterocyclic compound because it is found in various naturally occurring drugs, such as omeprazole, astemizole and emedastine difumarate[1]. The efficacy of sub- stituted benzimidazoles in the treatment of parasitic infections is well known[2~4]. Substituted benzimid- azole moieties are established pharmacophores in parasitic chemotherapy. Bis(2-benzimidazole) and some substituted bis(benzimidazol-2-yl)alkanes have attracted much interest …  相似文献   

2.
IntroductionBenzimidazole is an interesting heterocyclicring because it is present in various natural occur-ring drugs such as omeprazole,astemizole andemedastine difumarate[1] .The efficacy of substitu-ted benzimidazoles in the treatment of parasitic in-fections is well known[2 _ 4] .Substituted benzimida-zole moieties are the established pharmacophores inparasitic chemotherapy. Bis( 2 - benzimidazoles) andsome substituted bis( 2 - benzimidazolyl) alkaneshave attracted much attention of some …  相似文献   

3.
1 INTRODUCTION A variety of transition metal complexes with barbiturates have been prepared owing to their important roles in clinical detection and identi- fication of drug[1~5]. They have the general formula of M(Ⅱ)(barb)2L2, where M is a transition metal (Co, Cr, Zn, Cu etc), barb the anion of a substituted barbituratic acid and L an organic base, usually pyridine. In these complexes, the donor atom in the barbiturate anion is a deprotonated nitrogen atom and, the coordination …  相似文献   

4.
The nature of the Ga-Ga bonding in Na2[Arx*GaGaArx*](Arx* = C6H3-2,6-(C6H5)2) has been investigated and compared with that of in H2[Arx*GaGaArx*] using electron localization function(ELF) and orbital analysis.The calculation results show that in Na2[Arx*GaGaArx*],the Ga-Ga interaction is a non-classical triple bond,the heart of Na2[Arx*GaGaArx*] is the Ga2Na2 cluster rather than a simple Ga-Ga bond,and the contribution of the sodium atoms to the short Ga-Ga bond length is considerable.As the two sodium atoms are substituted by two hydrogen atoms,the Ga-Ga bond is replaced by two 3-center,2-electron(3c-2e) Ga-H-Ga covalent bridged bonding.  相似文献   

5.
Introduction The substitution of atom N for O in macrocyclic crown ether greatly influences its complexation. It is just expected that the complexing effects of the substituted macrocyclic on transition metals are greatly increased. The present paper covers the synthesis, structure and characterization of the complex [MnL(NCS)_2] of title macrocyclic ligand (L is 1-oxa-4, 7, 10-triazacy-  相似文献   

6.
A dibromo substituted BOPHY derivative(2) was prepared and found to exhibit photo-sensitization capability. Rapid oxidation of 80% DPBF at the first 6 min was observed suggesting that 2 is a superior photo-sensitizer than methylene blue. The HOMO–LUMO band gap for the lowest energy absorption bands of the BOPHY 1 is smaller than that of PS 2, which is in good agreement with the red shift in the absorption observed between 1 and 2.  相似文献   

7.
Cyclic ADP-ribose (cADPR) 1 (Figure 1), a intracellular Ca2+-mobilizing messenger, is of great interest because of its significant importance in the signal transduction1. However, the biological as well as chemical instability of cADPR limits the studies of its physiological role, at least in some aspect2. Recently, Shuto et.al.3 constructed a mimic of cADPR, cyclic IDP-carbocyclic-ribose 2, in which the 4'-oxo in furanose is substituted by a methylene group and the stability of 2 is i…  相似文献   

8.
An air and moisture stable ruthenium(Ⅲ) formate complex[Ru(HCO_2)Cl_2]_n has been synthesized and examined in the epoxidation of substituted styrenes.X-ray crystallographic data of this complex were determined and showed that the formate ligand coordinates to the ruthenium centers in a μ~2-η~2 fashion(syn,syn).Its asymmetric unit contains one Ru(Ⅲ) ion together with the half of a formate ligand and one chloride anion,which are bridged between the metal centers,forming a 1-D chain coordination polymer.This electron deficient helical coordination polymer was employed in the epoxidation of parafluorostyrene,affording the epoxide product in 92%yield.Natural chirality of this coordination polymer is applicable in asymmetric epoxidation reactions.  相似文献   

9.
Some interesting bimetallic isopropoxides of nickel(Ⅱ) with gallium(Ⅲ) and zirconium(Ⅳ), Ni[Ga(OPr~1)_4]_2 and Ni[Zr_2(OPr_1)_9]_2 have been synthesized by the interaction of NiCl_2·2Pr~1OH with K[Ga(OPr~1)_4],and K[Zr_2(OPr~1)_9] respectively, in 1:2 molar ratio. These bimetallic isopropoxides undergo facile alcohol interchange reactions with primary alcohols. However, reactions with tertiary alcohols result in the isolation of partially substituted derivatives with the compositions, Ni[Ga(OPr~1)(OBu~t)_3]_2 and Ni[Zr_2(OPr~1)_3(OBu~t)_6]_2. Characterisation of these derivatives has been made on the basis of elemental analyses, infrared, electronic spectral and magnetic susceptibility measurements. These studies suggest an octahedral geometry for nickel(Ⅱ) in the primary bimetallic alkoxides, while in the case of secondary and tertiary derivatives, an equilibrium is suggested between octahedral and tetrahedral forms.##属性不符  相似文献   

10.
1 INTRODUCTION The ability of dialkyldithiocarbamate anion, -S2- CNR2 (dtc) ligand, to bind metal has been known for many years[1, 2]. It forms a chelate with virtually all transition elements and is proven to be a versatile chelating agent for the separation and extract of metals in analytical chemistry and mineral floa- ting[3~5]. Water soluble dialkyldithiocarbamate com- plexes have been tested in various medical appli- cations[6]. Some of substituted dithiocarbamate salts also show …  相似文献   

11.
The title compound, (2R,3R)-3,5,7-trihydroxyflavanone 3-acetate, is a flavanonol derivative which was first isolated from Myoporum bontioides A. Gray and characterized by MS, NMR and CD spectra. In addition, the structure was determined by X-ray single-crystal diffraction analysis. It crystallizes in the triclinic lattice, space group P21 with a = 10.686(3), b = 6.862(2), c = 11.267(3) , β = 107.46(1), V = 788.3(4) 3, Z = 2, C17H16O7, Mr = 332.30, Dc = 1.400 g/cm3, μ(MoKα) = 0.110 mm-1, F(000) = 348, the final R = 0.0283 and wR = 0.0826 for 3428 independent reflections (Rint = 0.017) and 1500 observed ones (I > 2σ(I)). The structure consists of one flavone and one water molecule. The flavone molecules form a 1D column by the p…π stacking interactions and C–H…O hydrogen bonds. The weak intermolecular/intermolecular O–H…O hydrogen bonds observed in the crystal give further rise to a complicated network structure. Primary bioassay showed that the title compound has high inhibitory activity against Magnaporthe grisea with the EC50 values of 199.41 μg/mL.  相似文献   

12.
1 INTRODUCTION A great deal of interest in transition metal com- plex assembly has recently been devoted to the development of rational synthetic routes to novel one-, two- and three-dimensional crystal frameworks, due to their potential applications in…  相似文献   

13.
CHEN Hong  LIU  Ming-Guo 《结构化学》2012,31(7):959-964
The crystal structure of the new title compound (E)-ethyl 6-benzyl-2-[(cyclopropylmethylamino)(4-fluorophenylamino)methyleneamino]-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate ethanol monosolvate (C28H31FN 4O2S·C2H6O, Mr=552.70) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21/c with a=13.806(10), b=10.850(7), c=19.938(14), β=98.842(9)° , V=2951(4)3 , Z=4, Dc=1.244g/cm 3 , F(000)=1176, μ=0.153 mm-1 , MoKα radiation (λ=0.71073), R=0.0758 and wR=0.2234 for 4262 observed reflections with I > 2σ(I). Intramolecular N-H…S and C-H…N interactions as well as intermolecular N-H…O and O-H…N hydrogen bonds help to stabilize the crystal structure. X-ray diffraction analysis reveals that the asymmetric unit contains one title molecule and one ethanol molecule.  相似文献   

14.
1 INTRODUCTION Based on the reported 1.65 ? high resolution crystal structure of spinach KARI (ketol-acid reduc- toisomerase) complex[1], we obtained 279 molecules with low binding energy toward KARI from MDL/ ACD 3D database searching, using program DOCK 4.0[2]. These potential structures provide further information for the design of new KARI inhibitors, one of novel derivatives of which as the title com- pound has been synthesized. Its crystal structure will provide us more inf…  相似文献   

15.
1 INTRODUCTION Coordination-driven supramolecular assembly hasattracted great interest in constructing beautiful mo-tifs and developing new materials[1~5]. It is crucial toselect or synthesize suitable bridging organic li-gands[6~10]. The reduced Schiff base N-(2-hydro-xybenzyl)-D,L-amino acid is an excellent ligand forself-assembly with metal ions, not only due to itsprolific coordination sites but also its strong abilityto afford hydrogen bonding from secondary aminegroup and carbox…  相似文献   

16.
The new title compound N-(5-(4-chloro-2-(trifluoromethyl)phenyl)furan-2-carbon-yl)- N'-(4,6-dimethylpyrimidin-2-yl)thiourea (C19H14C1F3N4O2S) has been synthesized, and its crystal structure and biological behaviors were studied. The title compound crystallizes in the monoclinic system, space group P21/c with a = 7.932(5), b = 33.46(2), c = 7.556(5) A, β = 98.058(9)°, V = 1986(2) A^3 Mr = 454.85, Z = 4, Dc = 1.521 g/cm^3, μ = 0.349 mm^-1 and F(000) = 928. The structure was solved by direct methods and refined to R = 0.0724 and wR= 0.1429 for 3494 observed reflections (I 〉 2σ(I)). Intermolecular hydrogen bonds along the b axis together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary biological tests show definite herbicidalactivity for the title compound.  相似文献   

17.
The new title compound N-(5-(4-chloro-2-(trifluoromethyl)phenyl)furan-2-carbon-yl)- N?-(4,6-dimethylpyrimidin-2-yl)thiourea (C19H14ClF3N4O2S) has been synthesized, and its crystal structure and biological behaviors were studied. The title compound crystallizes in the monoclinic system, space group P21/c with a = 7.932(5), b = 33.46(2), c = 7.556(5) , β = 98.058(9)°, V = 1986(2) 3, Mr = 454.85, Z = 4, Dc = 1.521 g/cm3, μ = 0.349 mm–1 and F(000) = 928. The structure was solved by direct methods and refined to R = 0.0724 and wR = 0.1429 for 3494 observed reflections (I > 2σ(I)). Intermolecular hydrogen bonds along the b axis together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary biological tests show definite herbicidal activity for the title compound.  相似文献   

18.
以大豆苷元为先导化合物,合成了水溶性异黄酮化合物4’,7-二甲氧基异黄酮磺酸锂.X射线单晶衍射分析表明:标题化合物属于三斜晶系,空间群Pi,晶胞参数为:a=0.7732(2)nm,b=1.874(5)nm,c=1.920(5)nm,α=111.224(4)°,β=90.21(5)°,γ=100.68(4)°Z=2.标题化合物的分子组成为[Li(H2O)4]2(C17H13O4SO3)2·4H2O,其中两种类型的锂离子均被4分子水所配位.[Li(H2O)4]^+、C17H13O4SO3^-和H2O之间存在多种氢键作用;氢键作用以及阴阳离子之间的静电引力作用共同将标题化合物组装成具有三维网络结构的超分子.  相似文献   

19.
The crystal structure of the title compound (C19H17F3N2O4,Mr=394.35) was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group C2/c with a=28.383(6),b=10.355(2),c=12.799(3)(A),β=111.74(3)°,V=3493.8(12)(A)3,Z=8,De=1.499 g/cm3,λ(MoKα)=0.71073,F(000)=1632,μ= 0.127 mm-1,R=0.0412 and wR=0.1019.In the title compound,there exist three intennolecular hydrogen interactions (O(4)...O(1),O(4)...O(3) and O(4)...N(1)) between water.The neighboring molecules are linked to each other generating a two-dimensional network structure via the three intermolecular hydrogen bonds and π-π interactions shaped by phen-phen with centroid distance of 4.049 (A).  相似文献   

20.
翟君  徐立 《结构化学》2012,31(2):255-261
The title complex [Fe(CDTA)(H2O)]·[Fe(1,10-phen)3]·10H2O·2OH (CDTA = transcyclohexane-1,2-diamine-N,N,N,N′-tetraacetate) has been prepared and characterized by single-crystal X-ray diffraction analysis. The crystal adopts space group P with a = 12.793(4), b = 14.104(5), c = 17.880(5), V = 2792.2(1)3, Dc = 1.459 g/cm3, C50H66Fe2N8O21, Mr = 1226.81, F(000) = 1284, μ = 0.604 mm-1, Z = 2, R = 0.1055 and wR = 0.2581 for 8675 observed reflections (I > 2σ(I)). X-ray crystallography analysis exhibits that the title compound consists of two crystallographically independent molecules [Fe(CDTA)(H2O)] and [Fe(1,10-phen)3], and they are connected through O-H···O hydrogen bonds and π···π stacking interactions forming a 3D supramolecular structure. Interestingly, there is a cyclic water hexamer with chair conformation in this complex.  相似文献   

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