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2-取代亚肼基-1,3-二硫杂环戊烷类化合物的合成及其生物活性研究 总被引:9,自引:0,他引:9
以取代苯甲醛、取代吡啶和取代苯甲酸酯等为原料合成了 10种含硫杂环化合物 (其中 2a~ 2g化合物为国内外未见报道 ) .在合成过程中采用了超声波技术 ,极大地缩短了反应时间 ,提高了收率 .所得化合物的结构经IR ,1 HNMR ,MS和元素分析证实 .对其生物活性进行了初步测试 ,结果证明一些化合物具有良好的抑菌或杀菌作用 ,其中 2b ,2c ,2e ,2h ,2i和2j对大肠杆菌 ( 10 40 7号 )的抗菌效果与CET和SMZ相当 ;2b ,2c ,2f对草绿色链球菌 ( 112 3号 )的抗菌效果与CET和SMZ相当 . 相似文献
34.
Monoclonal antibody technique was employed to detect the conformational difference of CaM induced by metal ions. A trivalent europium ion induced conformation-specific anti-calmodulin monoclonal antibody was successfully prepared with europium-saturated calmodulin as antigen. 相似文献
35.
In this work, the surface properties of novel sugar-containing polymers, α-allyl glucoside (AG)/acrylonitrile (AN)copolymers, were studied by contact angle, protein adsorption and cell adhesion measurements. It was found that the contactangle of the copolymer films decreased from 68° to 30° with the increase of AG content in the copolymer. The adsorptionamount of bovine serum albumin (BSA) and the adhesive macrophage onto the film surface also decreased significantly withincreasing α-allyl glucoside content from 0 to 42 wt% in the copolymer. These preliminary results reveal that both thehydrophilicity and the biocompatibility of polyacrylonitrile-based membranes could be improved by copolymerizing acrylonitrile with vinyl carbohydrates. 相似文献
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铟锡氧化物纳米网的微波法制备及其光催化特性研究 总被引:2,自引:0,他引:2
By using ultrasonic and chemical liquid coprecipitation, the precursor was prepared with high purity In, SnCl4·5H2O and urea. The In2O3·SnO2 nanonets were obtained from precursor by heating in microwave oven. The powders were characterized by XRD, TEM. The analyzed results show the sample is In2O3·SnO2, and In2O3is rhombohedral system while SnO2 is tetragonal system. The sample is in spherical grain shape, with average granularity of 35 nm, and the mesh diameter of 10~80 nm. The sample was with fluorescence and good photocatalytic performance for degradation of organic dyestuff. 相似文献
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Huan Yang QI Chao Feng ZHANG Mian ZHANG Jian Qun LIU Zheng Tao WANG 《中国化学快报》2005,16(8):1050-1052
Three new anthraquinones, emodin-8-β-D-(2"-O-coumarate)glucoside 1, emodin-8-β-D-(6'-O-acetyl)glucoside 2 and physicon-8-β-D-(6'-O-acetyl)glucoside 3, were isolated from the roots of Polygonum cillinerve and their structures were established by spectroscopic methods. The biological activity indicated that compound 1 had the scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals (the IC50 = 8.5 μmol/L), and compound 1-3 showed no activities against HL-60 and BCJC-823 cells by MTT method in vitro. 相似文献
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Chao Zhang 《Tetrahedron》2007,63(26):5832-5838
The ability to inhibit any protein kinase of interest with a small molecule is enabled by a combination of genetics and chemistry. Genetics is used to modify the active site of a single kinase to render it distinct from all naturally occurring kinases. Next, organic synthesis is used to develop a small molecule, which does not bind to wild-type kinases but is a potent inhibitor of the engineered kinase. This approach, termed chemical genetics, has been used to generate highly potent mutant kinase-specific inhibitors based on a pyrazolopyrimidine scaffold. Here, we asked if the selectivity of the resulting pyrazolopyrimidines could be improved, as they inhibit several wild-type kinases with low-micromolar IC50 values. Our approach to improve the selectivity of allele-specific inhibitors was to explore a second kinase inhibitor scaffold. A series of 6,9-disubstituted purines was designed, synthesized, and evaluated for inhibitory activity against several kinases in vitro and in vivo. Several purines proved to be potent inhibitors against the analog-sensitive kinases and exhibited greater selectivity than the existing pyrazolopyrimidines. 相似文献