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苯丙素苷是从药用植物中提取出的具有取代苯乙基和取代肉桂酰基的一系列天然糖苷化合物的统称,其糖核一般由一到四个单糖构成.许多研究表明,这类化合物具有抗菌、抗病毒、抗肿瘤、镇痛、降压、治疗糖尿病和免疫调节等明显的生物活性[1],因此它们的合成研究已得到有机合成化学家的注意[2].二糖苯丙素苷Lugrandoside是从毛地黄属药用植物中分离出来的一种天然化合物[3],具有强的抗氧化活性[4].本文从D-葡萄糖出发,经过15步反应,得到了全保护的二糖(3,4-二-O-烯丙基)-β-苯乙基(2,3,4,6-四-O-乙酰基)-O-β-D-吡喃葡萄糖基(1→6)-4-O-(3,4-二-O-烯丙基)咖啡酰基-2,3-二-O-乙酰基-1-O-β-D-吡喃葡萄糖,脱去保护基团,最终合成出Lugrandoside的研究正在进行之中. 相似文献
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An efficient and practiacal procedure for the synthesis of dihydropyrimidinones from aldehydes,1,3-dicarbonyl compounds and urea under solvent-free reaction condition using zinc triflate as a catalyst is described.In comparison with the classical Biginelli reaction,the yields for this new procedure increased from 20%-50% to 75%-98% while the reaction time was significantly shortened from 18h to 20min. 相似文献
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聚乙二醇支持的二醋酸碘苯作为可溶性聚合物试剂可在温和的反应条件下将醛的苯基腙氧化成为腈亚胺中间体,该中间体进而可与丙烯酸甲酯发生1,3-偶极环回成反应,以良好的产率和完全的区域选择性生成吡唑啉衍生物。 相似文献
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抗癌活性鬼臼毒素衍生物的合成与构效关系研究 总被引:3,自引:2,他引:3
合成了13个新的鬼臼毒素衍生物5-17,经元素分析IR,MS,ESR和^1HNMR分析确证了其组成和结构,并对它们进行了抑制小鼠淋巴白血病P388和人胃腺癌SGC-7901细胞体外筛选,发现新化合物5,7-10对两种瘤株均有显著抑制活性,4′-O-去甲基鬼臼毒素5,10-13的抗癌活性大于相应的4′-甲氧基类似物6,14-17,用“-O-”桥取代C-4位的“-NH-”桥可导致抗癌活性降低。 相似文献
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Cuprous oxide (Cu2O) nanocubes have successfully been prepared through a simple and novel method by heating Cu(ethyl acetoacetate)2 (Cu(EAC)2) and poly(ethyleneglycol) (PEG) in the absence of other chemicals. The PEG acted as the reducing agent as well as the stabilizer. The XRD results indicated that no metal Cu or CuO developed in the preparation process, and only Cu2O nanoparticles with the cuprous structure were produced. The TEM images revealed that all the Cu2O nanoparticles were cubic-shaped or square-shaped particles. The size and shape of Cu2O nanocubes were dependent on concentrations of the Cu(Ⅱ) precursor, reactant temperatures, and chain length of PEGs. It is interesting that the reducing reactivity of PEG was sensitive to its chain length, and the reduction reaction activity was drastically dropped with the decreasing of polymer′s chain length. 相似文献
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综述了近年来聚乙二醇支撑的有机合成反应、试剂和催化剂的研究进展。参考文献30篇。 相似文献
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聚乙二醇支持的底物或试剂参与的小分子化合物的合成 总被引:1,自引:0,他引:1
对近年来聚乙二醇为可溶性聚合物支持体支持的底物或试剂参与的小分子化合物的液相有机合成反应进行了总结。参考文献36篇。 相似文献