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1.
新型四硫代富瓦烯衍生物的合成及其性质的研究   总被引:2,自引:0,他引:2  
合成了3个新的含有卤素取代基的四硫代富瓦烯衍生物及6个新的相关化合物。利用溶液的电子吸收光谱对四硫代富瓦烯衍生物的性质进行了研究。研究结果表明, 四硫代富瓦烯衍生物的分子中π轨道之间的能级差较小, 因而分子具有较高的稳定性。  相似文献   

2.
SummaryThethemeof 17ICCEisthatthenewcenturyoffersnewchallenges,newopportunitiesandnewhopesforchemicaledu cation .Theseaspirationsarecertainlycriticalforchemicaledu cationinAustralia ,particularlyatthetertiarylevel.Ithasbeenrecognizedforatleastthepasttwode…  相似文献   

3.
为建设高分子物理精品课程,近年来我们关注和跟踪高分子科学发展前沿,开设了"高分子材料流变学"、"高分子凝聚态物理"等新课,编著出版新教材。这些课程和教材的一个显著特点是不失时机地将学科发展的新动态、新成果引入研究生、本科生教学,提升高分子物理课教学质量。在编著新教材中,除介绍大量新知识、新思想外,还探索性地构建起新课程的理论体系和框架。  相似文献   

4.
According to Watson′s DSC principle, a new design of electric circuit of DSC was proposed, Referring to the instrument constraction of DSC of Perkin-Elmer corporation, a new instrument construction of DSC was designed.This new electric circuit and this new instrument construction can overcome the shortcomings in de- sign of DSC of Perkin-Elmer corporation, Figure 1 is a schematic diagram of the new electric circuit. The temperatures and enthalpies of phase transitions of stan- dard materials were measured by using the new DSC. The experimental results are shown in table 1.  相似文献   

5.
中国番荔枝科植物抗癌有效成分研究   总被引:6,自引:0,他引:6  
陈若芸  于德泉 《有机化学》2001,21(11):1046-1050
介绍了近年来我们实验室中国番荔枝科植物抗癌有效成分研究工作。从番荔枝科5种紫玉盘属植物,5种哥纳香属植物,1种番荔枝属植物,1种囊瓣木属植物中分离得到59种新的番荔枝内酯,32种新的多氧取代环己烯,12种新的苯乙烯吡喃酮和3种新的生物碱,并通过化学和光谱方法鉴定了它们的结构。大部分化合物显示了较强的抗癌活性。并对抗癌活性成分海南哥纳香醇甲进行了全合成。  相似文献   

6.
概念是有机合成化学发展的基础之一,新概念的产生和发展可为有机合成开拓新的研究领域和发展方向。此文介绍现代有机合成中的一些新概念和新方法,结合具体的有机合成反应实例展示有机合成在这些概念的基础上取得的新成果和新进展,并综合归纳了现代有机合成的发展方向和应重视的研究领域。  相似文献   

7.
Water-soluble constituents of Glehnia littoralis fruit   总被引:2,自引:0,他引:2  
From the water-soluble portion of the methanol extract of the fruit of Glehnia littoralis Fr. SCHMIDT ex MIQ. (Umbelliferae; "hamabofu" in Japanese), thirty compounds, including three new monoterpenoids and a new monoterpenoid glucoside, a new benzofuran glucoside, a new alkyl glucoside, and a new glucide, were obtained. Their structures were clarified by spectral investigation.  相似文献   

8.
In this paper we present new modified open Newton Cotes integrators and we develop a new modified trigonometrically-fitted open Newton-Cotes method. We study the connection between the new proposed schemes, the differential methods and the symplectic integrators. although The research on multistep symplectic integrators is very poor, although, much research has been done on one step symplectic integrators and several of then have obtained based on symplectic geometry. In this paper a new open modified numerical algorithm of Newton-Cotes type is produced. We present the new obtained method as symplectic multilayer integrator. The new obtained symplectic schemes are applied for the solution of the resonance problem of the radial Schrödinger Equation. The results show the efficiency of the new proposed algorithm.  相似文献   

9.
N-取代芳环-4-氨基喹唑啉类化合物的合成及生物活性研究   总被引:10,自引:0,他引:10  
刘刚  宋宝安  桑维钧  杨松  金林红  丁雄 《有机化学》2004,24(10):1296-1299
以4-氯喹唑啉和芳香胺反应,合成了三个新的N-取代苯环或杂环4-氨基喹唑啉类化合物.三个新化合物经1HNMR,IR及元素分析证明其结构.生物活性测试表明,三个新化合物均有一定的抑菌效果.  相似文献   

10.
A new three-parameter cubic equation of state is presented by combination of a modified attractive term and van der Waals repulsive expression. Also a new alpha function for the attractive parameter of the new EOS is proposed. The new coefficients of alpha function and the other parameters of the attractive term are adjusted using the data of the saturated vapor pressure and liquid density of almost 60 pure compounds including heavy hydrocarbons. The new EOS is adopted for prediction of the various thermophysical properties of pure compounds such as saturated and supercritical volume, enthalpy of vaporization, compressibility factor, heat capacity and sound velocity. Following successful application of the new EOS for the pure components, using vdW one-fluid mixing rules, the new EOSs are applied to prediction of the bubble pressure and vapor mole fraction of the several binary and ternary mixtures. The accuracy of the new EOS for phase equilibrium calculation is demonstrated by comparison of the results of the present EOSs with the PT, PR, GPR and SRK cubic EOSs.  相似文献   

11.
A new bicyclogermacrane sesquiterpenoid, two new cembrane diterpenoids and five new dolabellane diterpenoids, along with known terpenoids, have been isolated from the Malaysian liverwort Chandonanthus hirtellus. The structures of the new compounds were established by spectroscopic and chemical methods in addition to X-ray crystallographic studies.  相似文献   

12.
In the context of formation of new aza analogs of camptothecin, nitration then reduction of condensed pyridones was realized, leading to new derivatives of pyrrolo-aza-indoles. Treatment of these compounds with hydrobromic acid led to new structure rearrangements while oxidation of the α-position was unsuccessful. Mechanisms of formation of the new products are discussed.  相似文献   

13.
Water-soluble constituents of dill   总被引:1,自引:0,他引:1  
From the water-soluble portion of the methanol extract of dill (fruit of Anethum graveolens L.), which has been used as a spice and medicine, thirty-three compounds, including a new monoterpenoid, six new monoterpenoid glycosides, a new aromatic compound glucoside and a new alkyl glucoside were obtained. Their structures were clarified by spectral investigation.  相似文献   

14.
Water-soluble constituents of ajowan.   总被引:4,自引:0,他引:4  
From the water-soluble portion of the methanol extract of the fruit of Carum ajowan (ajowan), which has been used as a spice and medicine, 25 compounds, including five new monoterpenoid glucosides, a new monoterpenoid, two new aromatic compound glucosides, and two new glucides, were obtained. Their structures were clarified by spectral investigation.  相似文献   

15.
From the water-soluble portion of the methanol extract of coriander (fruit of Coriandrum sativum L.), which has been used as a spice and medicine since antiquity, 33 compounds, including two new monoterpenoids, four new monoterpenoid glycosides, two new monoterpenoid glucoside sulfates and two new aromatic compound glycosides were obtained. Their structures, were clarified by spectral investigation.  相似文献   

16.
Tse WC  Boger DL 《Chemistry & biology》2004,11(12):55-1617
Biologically active, therapeutically useful, DNA binding natural products continue to reveal new paradigms for sequence-selective recognition, to enlist beautiful mechanisms of in situ activation for DNA modification, to define new therapeutic targets, to exploit new mechanisms to achieve cellular selectivity, and to provide a rich source of new drugs. These attributes arise in compact structures of complex integrated function.  相似文献   

17.
A new design for the coated piezoelectric crystal detector cell is described; this provides very high sensitivity. Triethanolamine and quadrol are the new substrates used for the detection of sulfur dioxide. The new design and the new coatings together make possible the selective detection of sulfur dioxide in nitrogen even at p.p.b. levels.  相似文献   

18.
An extract of Keiskea japonica MIQ. showed an inhibitory effect on hyaluronidase activity. From the extract, four new phenylpropanoids, two new maltol glycosides, two new monoterpene glycosides, and two new phenolic compounds were isolated together with 19 known compounds. Among these constituents, two phenylpropanoids and a flavone glucuronide were revealed as hyaluronidase inhibitors.  相似文献   

19.
A new homogeneous fullerenated carbazole polymer has been synthesized, revealing a new substitution pattern for carbazole and a new photodecomposition-resistant substitution pattern for fullerenes. The synthetic method may be accomplished in one pot via acid catalyzed alkylation. The new polymer has several unusual photovoltaic, charge storage, and photoconductivity capabilities. © 1994 John Wiley & Sons, Inc.  相似文献   

20.
Molecular two-photon spectroscopy is promising to be a new tool for finding otherwise forbidden spectroscopic transitions. Work in the gas phase is particularly important for a study of vibronic two-photon states. The proof of such a new method, at least in part, must be based on its ability to make new assignments. Benzene has up to now been the first, and only example for new assignments. We now present naphthalene as a second system for this new technique. Assignments of new states are presented and based on a spectrum at a pressure of only 70 mtorr. The analysis makes use of rotational structure, polarization behavior and hot band information. We assign not only six new fundamentals in the first excited singlet state 1B3u but also fix some ground state assignments, which were ambiguous in the IR spectrum.  相似文献   

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