共查询到20条相似文献,搜索用时 78 毫秒
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Combretastatin A-4是一类结构独特的天然产物,具有较好的抗肿瘤活性。为了进一步研究该类化合物的构效关系,以3,4,5-三甲氧基苯甲醛和3-羟基-4-甲氧基苯乙酸为原料,在碱性条件下经缩合、酰化反应合成了5个未见文献报道的Combretastatin A-4衍生物。并通过~1HNMR、~(13)CNMR和MS对其结构进行确证。采用MTT法对合成的目标产物体外抗肿瘤活性进行了初步测定。结果表明,(E)-N-(2-(二甲氨基)乙基)-2-(3-羟基-4-甲氧基苯基)-3-(3,4,5-三甲氧基苯基)丙烯酰胺和(E)-2-(3-羟基-4-甲氧基苯基)-N-(2-(吡咯烷-1-基)乙基)-3-(3,4,5-三甲氧基苯基)丙烯酰胺对K562肿瘤细胞有较弱的抑制作用。 相似文献
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该文基于Perkin反应合成了具有血管阻断及抗肿瘤活性的天然产物Combretastatin B-1(CB1)。以异香兰素为起始原料,用二溴海因对其进行选择性溴代得到2-溴-3-羟基-4-甲氧基苯甲醛(Ⅱ),该化合物与3,4,5-三甲氧基苯乙酸(Ⅲ)发生Perkin反应得到(Z/E)-2-(3,4,5-三甲氧基苯基)-3-(2'-溴-3'-乙酰氧基-4'-甲氧基)丙烯酸(Z-4、E-4),再经羟化反应及脱羧-异构化反应制备得到E-Combretastatin A-1(E-CA1),最后经催化氢化反应得到CB1,总收率为53.4%。 相似文献
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目的:研究微波辅助法提取积雪草黄酮类化合物效果。方法:选择积雪草材料,使用热风烘干、自然风干和微波辅助方法,判断烘干效果以及黄酮类化合物的提取有效性。结果:微波干燥方法微波功率为406W、时间为90s、乙醇浓度为70%、固液比为1∶20,提取出积雪草黄酮类有效物质的效果最好。结论:使用微波辅助法能更有效地烘干积雪草,并顺利提取出其中的黄酮类化合物。 相似文献
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本文通过单因素实验确定了微波法提取北五味子中黄酮类化合物的最佳实验工艺条件,并确定了微波法相比于其它方法的优越性. 相似文献
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研究了以3,4-二氯硝基苯为原料通过卤素交换氟化合成3-氯-4-氟硝基苯的反应。结果表明,微波加热条件下反应速率是常规加热的3~12倍。收率和选择性也都有提高。金属Lewis酸A1C13和SbCl3用作本反应的催化剂可以取得良好的效果,其中SbCl3效果最好,用于400W微波加热反应10min可得到97.0%的收率。 相似文献
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以硫酸氢钠为催化剂,采用微波辐射,由间苯二酚与乙酰乙酸乙酯缩合制备7-羟基-4-甲基香豆素。结果表明,微波辐射合成7-羟基-4-甲基香豆素的最佳反应条件为:n(间苯二酚)∶n(乙酰乙酸乙酯)=1.0∶1.0,硫酸氢钠0.4 g,10 mL环己烷,反应温度100℃,微波辐射时间12 min,微波功率500 W,产率91.0%。 相似文献
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以苄胺和丙烯酸甲酯为起始原料,对于Michael加成、Dieckmann缩合采用微波辐射的方法,分别对不同的微波辐射时间、微波功率、微波温度进行了试验,最佳的Michael加成条件是:微波功率设定为110~120 W,微波反应温度设定为50~55℃时,微波辐射80 min,最佳的Dieckmann缩合条件是:在微波功率... 相似文献
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Franziska Reipsch Bernhard Biersack Henrike Lucas Rainer Schobert Thomas Mueller 《International journal of molecular sciences》2021,22(23)
Specific targeting of the tumoral vasculature by vascular-disrupting agents (VDA), of which combretastatin A-4 (CA-4) is a main representative, has been considered a new therapeutic strategy against multidrug-resistant tumors. In addition, CA-4 and analogs are tubulin-targeting agents and can exert direct antitumor effects by different mechanisms. Herein, we analyzed a series of synthetic CA-4 analogs featuring N-methylimidazole-bridged Z-alkenes with different halo- or amino-substituted aryl rings in vitro and in vivo, focusing on models of colorectal cancer. Combined in vitro/in vivo structure–activity relationship studies using cell lines and xenograft tumors susceptible to VDA-induced vascular damage demonstrated a clear association of cytotoxic and vascular-disrupting activity with the ability to inhibit tubulin polymerization, which was determined by specific substitution constellations. The most active compounds were tested in an extended panel of colorectal cancer (CRC) cell lines and showed activity in CA-4-resistant and chemotherapy-resistant cell lines. The bromo derivative brimamin was then compared with the known fosbretabulin (CA-4P) by activity tests on DLD-1- (multidrug-resistant) and HT29- (CA-4-resistant) derived xenograft tumors. Treatment did not induce pronounced vascular-disrupting effects in these tumors. Histological analyses revealed distinct tumor substructures and vessel compositions of DLD-1/HT29 tumors, which clearly differed from the tumor models susceptible to VDA treatment. Even so, brimamin effectively retarded the growth of DLD-1 tumors, overcoming their resistance to standard treatment, and it inhibited the outgrowth of disseminated HT29 tumor cells in an experimental metastasis model. In conclusion, combretastatin analogous N-methylimidazoles proved capable of inducing vascular-disrupting effects, comparable to those of CA-4P. In addition, they showed antitumor activities in models of drug-resistant colorectal cancer, independent of vascular-disrupting effects. 相似文献
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Mg4Nb2O9具有与α-Al2O3相同的刚玉型晶体结构,可望成为取代氧化铝陶瓷的新一代高Q值基板材料.TG-DTA(热失重-差热)和X射线衍射分析表明,Mg4Nb2O9的合成温度低于900℃.在900~1400℃温度范围内,采用固相反应法合成了Mg4Nb2O9化合物.相结构检测分析表明,生成物中除了主晶相Mg4Nb2O9外,还含有MgNb2O6和MgO2种物相;Mg4Nb2O9相的最佳合成温度为1300℃.同时,对Mg4Nb2O9陶瓷的微波性能进行了测试分析,得到了ε为13.1,Q·f为136682 GHz的较好性能. 相似文献
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以CoCl2·6H2O和AlCl3为起始原料,NaOH为沉淀剂,用微波水热法合成了纳米CoAl2O4钴蓝色料.分别研究了填充度、pH值、nCo/nAl、起始原料浓度等对合成色料物相组成、颗粒大小与形貌和呈色的影响.用XRD、TEM和色度仪对样品进行了表征.结果表明:CoCl2·6H2O和AlCl3的浓度分别为0.15 mol/L和0.30 mol/L,在填充度为50%、pH值为13、nCo/nAl为1∶2的条件下,230℃微波水热反应3h可制得呈色较好的尖晶石型钴蓝色料;其形态为八面体,晶型完整、发育良好,粒径多为70~80 nm左右. 相似文献