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1.
Styrylstilbenes and their derivatives are a kind of organic luminescent materials. A variety of synthetic methods have been reported, and their physical properties have been studied. [1,2] A series of para-substituted styrylstilbenes were synthesized by Wittig or Arbusor-Horner reaction as a key step forming C=C bonds.  相似文献   

2.
Isoflavones have been found a wide range of applications as natural antioxidants being suggested in diet as a gents responsible for the prevention of coronary diseases, breast and prostate cancer. [1] Most of the isoflavones have been isolated from natural sources and their simple structural features lead to the development of many synthetic methods. [2] Here we synthesized a new trihydroxyisoflavone.  相似文献   

3.
Many dihydropyrimidinones and their derivatives play an important role in medicine due to their therapeutic and pharmacological properties. [1] They have emerged as the integral backbones of several calcium channel blockers, antihypertensive agents, alpha-1α-antagonists. [2] Strategies for the synthesis of dihydropyrimidinone nucleus have varied from one-pot to multistep approaches. Although high yields can be achieved by the following complex multistep procedures, these methods lack the simplicity comparing with Biginelli protocol which firstly reported by Biginelli by one-pot condensation of aryl aldehyde, β-ketoesters and urea with catalytic acid in 1993, and these multistep methods suffer from low yields particularly for substituted aromatic aldehyde.  相似文献   

4.
Silica hollow spheres(SHSs) have attracted great attention because of their low toxicity,low density,large surface area,high chemical and thermal stability,and surface permeability.They can be widely applied in storage[1],catalysis[2],drug delivery[3,4],low-dielectric-constant materials[5],low-refractive materials[6-8],and so on.Up to now,there have been various methods to produce SHSs.Inorganic[9] or organic particles[10],such as polystyrene or calcium carbonate,were used as hard templates to create hollow cavities.However,the multistep synthetic process and the lack of structural robustness of the shells upon template removal process weaken their application.Soft templates,including oil-in-water emulsions[1],[2],vesicles[13],micelle[14,15] and gas bubbles[16],are applied widely.  相似文献   

5.
(+)-Boronolide (1) and its deacetylated products have attracted much attention of synthetic chemists due to their diverse biological properties as well as their structural complexities.[1] Many of these reported synthesis involved dehydrogenation of δ-lactone by using benzeneseleninic anhydride or ring-closing olefin metathesis (RCM) to introduce the requisite α,β-unsaturated δ-lactone in boronolide. Here, we report the synthesis of boronolide with diastereoselective propargylation of α-hydroxy aldehyde as the key step and D-gluconolactone as the starting material.  相似文献   

6.
β-hydroxy-α-amino acids constitute an important class of compounds as naturally occurring amino acids and as components of many complex natural products possessing a wide range of biological activities. [1] As a consequence of the essential role played by these amino acids in the biological systems and their utility as synthetic building blocks, a number of useful strategies have been devised for their preparation. [2]  相似文献   

7.
Several kinds of potential pregnancy terminating agents have been identified such as 2-aryl pyrazolo [5,1-a] isoindoles and isoquinolines1, pyrazolo[1,5-a] indoles and quinolines2, 3,5-diaryl-s-triazoles3, 2-phenyl triazole, pyrozole, imidazole isoindoles and homologues4 etc. In order to investigate their structure-activity relationship, the quantitative structure-activity relationship (QSAR) of 2-aryl imidazo [2,1-a] isoquinolines5 has been studied with multiple regression and BP Artificial…  相似文献   

8.
1 INTRODUCTION Acridine derivatives are described to have many applications, such as biological fluorescent probes[1] as well as anti-tumor[2], anti-bacterial[3], anti-HIV[4] and anti-malarial[5] agents. Because of the importance of acridine derivatives, much work has been done for several decades. Among them the classical synthetic methods involve condensing functionalized anilines and o-halogeno- benzoic acid derivatives as well as several other steps resulting in the desired acridine[…  相似文献   

9.
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   

10.
1 INTRODUCTION There has been extensive interest in the synthesis of heteroxometallates owing to their fascinating pro- perties and great potential applications in many fields, such as catalysis, material science, medicine and magnetochemistry as well as their unusual topo- logical properties[1~4]. Although various preparation methods have been proposed for the preparation of such materials, to find new synthetic method for novel compounds in this field is still one of the major chal- le…  相似文献   

11.
Polymer hydrogels as a kind of soft materials have attracted increasing scientific and technological interest in past several decades. These materials have been applied widely in many fields [1], such as molecular filter [2,3], superabsorbent [4], and contact lenses [5] etc. However, synthetic polymeric hydrogels are seldom used as mechanical devices due to the lack of mechanical strength. Therefore, it is very imperative to improve their mechanical properties for wider use of polymeric hydrog…  相似文献   

12.
In this paper, an efficient synthesis of cyclopentenyl ketones and cyclohexenyl ketones through tertiary phosphine catalyzed [3 + 2] and [4 + 2] annulations of 1,2-allenic ketones with activated alkenes has been developed. Compared with published synthetic methods on cyclopentenyl ketones and cyclohexenyl ketones, the protocols developed in this paper have the advantages such as readily available starting materials, mild reaction conditions and high efficiency.  相似文献   

13.
First Total Synthesis of Four Benzodioxane Neolignans   总被引:1,自引:0,他引:1  
During the last years, 1,4-benzodioxins and 1,4-benzodioxanes have attracted considerable interest, mainly due to their very interesting biological activities. Some of them act as (- or (-blocking agents and could be used in antidepression or antihypertension therapy1. Others exhibit antihyperglycemic properties2, or could act as inhibitors of 5-lipoxygenase3. Moreover, these compounds could also be used for useful synthetic transformations4. While there are many synthetic methods for the synt…  相似文献   

14.
1 INTRODUCTION Many efforts have been devoted to the synthesis of metal organophosphonates during the past three decades because of their rich variety of structural chemistry as well as their practical or potential applications in the areas of adsorption/desorption[1, 2], catalysts[3, 4], meso-/microporous materials[5~7] and intercalation chemistry[8~16]. One encouraging deve- lopment direction is the use of phosphonic acids with bi- and trifunctional groups, such as amino, hydroxyl and…  相似文献   

15.
IntroductionAnalytical methods based on chemilumi-nescence( CL ) reactions have received considerableattention for theirapplication in various fields,ow-ing to their extremely high sensitivity along withother advantages such as wide linear dynamicrange,simple instrumentation,easy miniaturiza-tion and coupling to various separation tech-niques[1— 6] .CL sensors have been developed for be-ing used as the continuous and real- time monitorsof inorganic,organic,biological and pharmaceuti-cal comp…  相似文献   

16.
<正>Serious diseases, particularly cancer, consistently pose significant threats to both national health and economic development[1]. The cancer diagnosis methods such as fluorescent probes [2,3],as well as treatment techniques including photodynamic treatments [4] and targeted drugs [5] have attracted much attention in recent years. The development and practical application of these methods have become focal points within research works.  相似文献   

17.
Zeolite beta is a large-pore crystalline aluminosilicate, which was first synthesized by Wadlinger et al[1] in 1967. Due to its peculiar framework topology and suitable acidity, zeolite beta has received increasing industrial interest for some important reactions such as alkylation of benzene with light olefins[2] and alkylation of isobutane with butene[3]. Many literature papers have reported methods to modify the acidity of zeolite beta, which include ion-exchange, hydrothermal treatment, and acid treatment.  相似文献   

18.
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   

19.
1 INTRODUCTION The design and construction of coordination fra- meworks are of great interest due to their intriguing structural motifs and potential applications as func- tional materials[1~4]. Many interesting fra-meworks with different dimensionalities have been obtained through self-assembly of selected metal centers and tailored ligands[5, 6]. Among them, dicarboxylate ligands, such as terephthalate[7, 8], isophthalate[9~12] and succinate[13, 14], are often used as bridges to bond m…  相似文献   

20.
IntroductionThe drug- molecules are called as silyl- drug ifasilicon atom replaced one carbon atom of theorganic- drugs.Generally,they have low toxicityand pro- long efficiency.Many methods have beendesigned in order to decrease the toxicity oforganotin compounds and organosilicon which hasbeen proved to be effective.Torque[1] is a newacaricide made by America Shell Company,itsmolecular formula is [( Ph Me2 Si CH2 ) 3 Sn]2 O.Tacker[2 ] synthesized the compounds( Ph Me2 Si CH2 ) 3 Sn X[…  相似文献   

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