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941.
A new polyoxomolybdate complex HNa7[Mo36O112(H2O)16]·47H2O 1 has been prepared in the beaker solution and characterized by single-crystal X-ray diffraction and elemental analyses. Crystal data: H127Mo36Na7O175, Mr = 6542.79, monoclinic, C2/c, a = 40.891(6), b = 17.900(3), c = 25.580(4) , β = 125.673(2)°, V = 15210(4) 3, Z = 4, Dc = 2.857 g/cm3, F(000) = 12464, μ = 3.013 mm-1, R = 0.0633 and wR = 0.1654 (I > 2σ(I)). With the bridging sodium cations, the [Mo36O112(H2O)16]8- units in compound 1 are linked to form a one-dimensional structure, on the basis of which a three-dimensional architecture is further constructed via other sodium cations and complicated hydrogen bonds.  相似文献   
942.
1 INTRODUCTION The synthesis and study of transition metal com- pounds incorporating organic free radicals directly bound to their coordination sphere are a major re- search aim in the field of molecular magnetism[1]. Exceptional stability, ease of chemical modification and versatility in their coordination properties have made nitroxide free radicals one of the most attrac- tive spin carriers for the design of molecular magne- tic materials[2, 3]. The structures and magnetic prope- rties …  相似文献   
943.
Design and Synthesis of Glycosylated Aromatic Nitrogen Mustard Derivatives   总被引:3,自引:0,他引:3  
Antibody-directed enzyme prodrug therapy(ADEPT) is a new strategy for the treatment of cancer that has arisen in recent twenty years, the main merits of which are that it can improve the selectivity of anticancer drugs and reduce the side effects in remote tissue. In the present study, two prodrugs-glycosylated aromatic nitrogen mustard derivatives were synthesized. Glucose and lactose were converted into glycosyl donors-trichloroacetimidate; the obtained glycosyl donors were glycosylated with p-nitrophenol(glycosyl donors) to form β-glucosyl p-nitrobenzene and β-lactosyl p-nitrobenzene that were protected by acetyl in a stereoselective manner; the two products were reduced by zinc dust and then treated with ethylene oxide, afforded two glycosylated nitrogen mustard derivatives that were protected by acetyl; the last step was to deacetylate and then afforded the two target compounds that could be used as prodrugs of ADEPT for further Anti-tumor research.  相似文献   
944.
为寻找新的高活性农药 ,根据生物等排原理 ,设计合成了 10种未见文献报道的N′ 5 ( 1H 1,2 ,3 ,4 四唑基 ) N 芳甲酰基硫脲类化合物 .它们的结构经IR ,1HNMR和元素分析确证 .初步的生物活性测定结果表明 ,部分化合物具有优良的除草活性或植物生长调节活性 .  相似文献   
945.
合成了两种新的聚醚取代的水杨醛亚胺Schiff碱锰(III)配合物MnL12Cl和MnL2Cl,研究了它们与表面活性剂2Brij35形成的金属胶束对BNPP的催化水解反应.探讨了催化反应机理,提出了水解反应的动力学数学模型;计算了催化反应的Michanelis常数和表观活化能,并与不含聚醚链的类似物MnL2Cl比较,考查了配合物配体中聚醚支链及其3端基对催化水解反应的影响.结果表明,催化水解反应遵循金属-氢氧离子机理;以羟基作为聚醚链端基的MnL12Cl的催化活性最高,在相同条件下,其表观一级速率常数约为MnL2Cl的3倍,为MnL2Cl的30倍.23  相似文献   
946.
Our previous paper1,2reported the results of selective synthesis of mannose type glycosides and their dimers in our attempt to synthesize derivatives of N-acetyllacto- samine, which could have potential activity of anti-metastasis3. Further studies on the glycosylation of the accepters exploiting glycosyl nitrate instead of the acetate as donor showed interesting chemoselectivity between the two kinds of donor, namely, the glucose type and the mannose type. The reactivity difference of the t…  相似文献   
947.
烷氧桥相连的四苯基双金属卟啉配合物的红外光谱研究   总被引:1,自引:1,他引:1  
研究了烷氧桥相连的四苯基双卟啉及其Mn(Ⅱ),Fe(Ⅲ),Co(Ⅱ)配合物的红外光谱(3600~150cm^-1),对一些主要吸收谱带进行了经验归属,金属敏感谱带出现1558.2(以H2P-H2P为例)、1477.2,1401.9,1350.5,1001.7,965.9,877.3和798.8cm^-1附近,金属和烷氧桥都敏感的谱带出现在1595.1(以H2P为例)、1491.1,851.1和72  相似文献   
948.
分别在水溶液中和W/O型CTAB/正戊醇/异辛烷/水微乳液体系中研究了测定SOD酶活性的邻苯三酚法,发现在反向微乳液中,"小水池"的低介电常数和pH抑制了底物超氧化物阴离子O2-·的产生.只有提高外加缓冲液的pH或"小水池"的水化度,才能得到所需浓度的O2-·,从而初步解决了在微乳液中SOD作用底物的产生问题,为在微乳液中准确测定SOD酶活性创造了条件.  相似文献   
949.
wo aα,w-dipolar amphiphiles, 10, 12-docosadiyne-1, 22-dicarboxylicacid (DDCA) and 10, 12-docosadiyne-1, 22-diol(DDOL)were synthesized by coupling the corresponding 10-undecylcarboxylic acid and 10-undecynol, respectively. They could form hybrid liposomes when ultrasonically dispersed with dimyristoylphosphatidylcholine (DMPC) at equal molar ratio. Liposome formation was confirmed by electron microscopy, UV measurement as well as encapsulation of fluorescent probes. UV irradiation of the mixed liposomes induced the polymerization of DDCA and DDOL on the liposomes, which could be followed by UV-Vis measurement.  相似文献   
950.
Room temperature ionic liquids (RTILs) as advanced, technological solvents can be designed to fit a particular application. They used as green “media and/or catalysts” for chemical synthesis have been extensively reviewed recently. RTILs1 not only show …  相似文献   
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