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1.
1 INTRODUCTION Since the discovery of buckministerfullerene (C60)[1], experimental and theoretical studies of the structure and properties of fullerenes have spread worldwide. Many experimental studies appeared on their syntheses[2], isolation[3], and characterization[4]. Theoretically, except studies on their chemical pro- perties[5], most of the work was concentrated on their interesting geometric[6~8] and electronic structures[9, 10]. For example, the ground state of C48 has C2 symme…  相似文献   

2.
Derivatized polyoxometalates (POMs ), especially those including organic andorganometallic components, have received current attention due to their potential applicationin catalysis, medicine and material sciences~[1]. For these reasons, several research groupshave devoted their efforts to the synthesis of organic and organometallic derivatives of heteropolyanions~[2]. However, the studies on organophosphorus-substituted heteropolyanionshave been reported rarely. Recently, a unique study on …  相似文献   

3.
1 INTRODUCTION Palladium compounds have attracted much attention as a consequence of their application in homogeneous and heterogeneous catalyses[1]. For instance, palladium compounds are the most active catalysts for the carbonylation, such as palladium-catalyzed carbonylation of nitroarenes, aryl halides, alkyne and so on[2~4]. Some dramatic results in the homogeneous catalysis of the reactions of organic compounds, particularly the successful commercial exploitation of the Wacker on…  相似文献   

4.
1 INTRODUCTION During the past years, dicarboxylic acids have been widely used as one polydentate ligand invo- lved in various metal chelation reactions to form transition or rare earth metal complexes with inter- esting properties in material science[1] and biological systems[2]. For example, Kim Y and his coworkers focused on the synthesis of copper(II) complexes containing malonate and pyrazine ligands to study their magnetic property and electronic conducti- vity[3]. The importance o…  相似文献   

5.
1 INTRODUCTION Many crown ethers have been synthesized[1, 2] and widely used[3~5]. The amide-type acyclic poly- ethers with versatile molecular structures offer many advantages over the traditional crown ethers, such as their potential activity for ion-selective electrodes[6] and the extraction of metal ions[7], so they have attracted much scientific attention[8~10]. In an effort to investigate the effect of skeleton of acyclic polyether on the extractability of metal ions, and to find …  相似文献   

6.
1 INTRODUCTION With the methods of [2+3] and [1+1] tripodal condensation of polyaldehyde with polyamine, many Schiff bases and their relative reduced polyaza cryptands have been facilely synthesized in high yields[1~5]. In this one-step route, some metal ions such as alkali[2, 6, 7], alkali earth[8], rare earth[9, 10] and other transition ions[4, 11, 12] were used as templates[13, 14]. Formerly, the dialdehydes are needed to be rigid structures[15] to prevent themselves from polymeri…  相似文献   

7.
1 INTRODUCTION Metallosupramolecular species with metal-metal interactions have been designed and synthesized due to their potential applications as functional materi- als[1]. For Ag(I) coordination compounds, short Ag(I) –Ag(I) separations have been found in many bi- and polynuclear complexes[2~4], and these short metal- metal distances have been attributed to the ligand ar- chitecture[5, 6]. Thus, the rational design of bi- and polynuclear Ag(I) complexes must recognize the in- here…  相似文献   

8.
1 INTRODUCTION Owing to their biological activities and chemical/industrial versalities, considerable attention has been continually attracted to metal-hydrazine complexes. For instance, Schiff base hydrazine and its analogues have been well studied in order to better understand the action mechanism of Vitamin B6-containing enzymes[1~3]. Six-coordinated copper(Ⅱ) complexes are of considerable interest, mainly due to their coordination geometry and spectroscopic properties[4]. Due to th…  相似文献   

9.
1 INTRODUCTION The transition metal complexes containing ferrocene ligand arouse the interest of chemists because of their novel structures and special properties[1]. The ferrocene derivatives have been used in electrochemistry, in nonlinear optics, and as molecular ferromagnets. Some complexes of 1,1′-bis(diphenylphosphino)ferrocene (dppf) have been synthesized, and many of their crystal structures have been reported by far[2~5]. Here we report the synthesis and crystal structure of a …  相似文献   

10.
1 INTRODUCTION Chiral amino acids and their versatile derivatives are very useful compounds in many fields[1]. In com- parison with well-documented chiral α and β amino acids and amino alcohols, the studies of chiral γ, δ… ω amino acids and amino alcohols deserve more attention. For example, there have been numerous reports on versatile functions of γ aminobutyric acid (GABA) produced from L-glutamic acid in the presence of L-glutamate decarboxylase (GAD)[2]. However, the stereo…  相似文献   

11.
1INTRODUCTION Investigation of the coordination chemistry of copper(II)continues to be stimulated by interest in developing modes for copper proteins and in under-standing the factors which give rise to the seemingly infinite variety of distortions from regular stereo-chemistry observed in Cu(II)complexes[1,2].For more than decades,due to the unique coordination polyhedra and their easy preparation,tripodal copper complexes have attracted much attention in addition to their special chemi…  相似文献   

12.
1 INTRODUCTIONOrganophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine. During the past two decades, (-ketophosphonates and their derivatives have attracted considerable attention because these compounds are endowed with special physical, chemical and pharmacological properties due to the proximity of the carbonyl and the phosphoryl groups[1~6]. For example, it is well known that phosphonoformic acid (PFA) is effectiv…  相似文献   

13.
1 INTRODUCTION The synthesis of Mo(W)/Cu(Ag,Tl)/S polymeric complexes from the reactions of [MS4]2- (M = Mo, W) with Cu , Ag or Tl remains attractive due to their rich coordination chemistry[1~10] and NLO ma- terials[7, 10]. For example, the reacti…  相似文献   

14.
1INTRODUCTION In recent years,dicarboxylic acids have been wide-ly used as poly-dentate ligands involved in various metal chelation reactions to form transition or rare earth metal complexes with interesting properties in material science[1~3]and biological systems[4~7].For example,Kim,Y.and his coworkers focus on the syn-theses of copper(II)complexes containing ligands of malonate and pyrazine to study their electronic con-ductivity and magnetic property[8].The importance of Tr(II)/dic…  相似文献   

15.
A series of phenylbenzamidine analogs were synthesized and tested for their biological activities of inhibiting the reuptake of 5- HT. All of them were new compounds, and their structures were confirmed by 1HNMR, MS and XRD.  相似文献   

16.
1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…  相似文献   

17.
1 INTRODUCTION Interest in transition-metal sulfides arises from their significance in industrial catalysis and biolo- gy[1]. Transition-metal sulfides as versatile catalysts are often less susceptible to poisoning and show higher selectivity than their corresponding oxides[2]. In fact, the transition-metalion chemistry has been an active area for both experimental and theoretical studies[3~10]. Recently, Schwarz’s and Armentrout’s working groups[11, 12] have reported the experimenta…  相似文献   

18.
1 INTRODUCTION As purine analogs, pyrzolo[3,4-d]pyrimidines have anti-tumor[1], antibacterial[2] and anti-leukemic activities[3,4]. Few of these, however, have been studied for pesticidal activity. It is reported that some substituted pyrzolo[3,4-d]pyrimidines have good fungicidal activity[5~7]. These prompted us to study pyrazolo[3,4-d]pyrimidines analogs further. It is shown that two possible products can be formed in the reaction of ethyl N-pyrazolylformimidate with alkylamines as sh…  相似文献   

19.
Steered molecular dynamics simulations of protein-ligand interactions   总被引:1,自引:0,他引:1  
Molecular recognition and specific protein-ligandinteractions are central to many biochemical processes,such as enzyme catalysis, assembly of organelles, en-ergy transduction, signaling, diverse control functions,and replication, expression and storage of the geneticmaterial[1]. Moreover, protein-ligand interactions pro-vide the mechanism of many drug therapies and un-derstanding of such interactions is thus significant forrational drug design[1,2]. For the experimental studiesof protein-ligan…  相似文献   

20.
1 INTRODUCTION The design, development and marketing of new chiral drugs are now a major theme in the drug chirality research and industry[1]. In 1996, the FDA announced it would consider further incentives for developing single isomer drugs because of their bet- ter pharmacokinetics prosperity, safety, and tolera- bility. Our recent drug candidate, 9α-(3-azabicyclo- [3,3,1]nonanyl)-2?-cyclopentyl-2?-hydroxyl-2?-thien- ylacetate I, is a potential selective M1 antagonist. It is composed…  相似文献   

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