monobromoalkene, a combination of hydrosilylation/vinylsilane hydrolysis and a palladium-catalyzed semi-hydrogenation step, using DMF/KOH as the hydrogen source. Our studies led us to prepare a series of diarylacetylene derivatives via a Sonogashira coupling reaction, and also to find out a copper-free basic cyclization leading to benzo[b]thiophenes. The final choice for the synthesis method of 1 strongly depends
研究了几种制备(Z)三甲氧基苯乙烯衍生物1的方法。在发现Wittig反应导致不满意的结果后,考虑了三种不同的策略:使用DMF / KOH作为氢源的Suzuki偶联与立体定义的单溴烯烃,氢化硅烷化/乙烯基硅烷水解和钯催化的半氢化步骤的组合。我们的研究使我们通过Sonogashira偶联反应制备了一系列二芳基乙炔衍生物,并且发现了无铜的碱性环化反应,从而生成了苯并[ b ]噻吩。1的合成方法的最终选择 强烈依赖于目标化合物,但通常应优先选择避免使用有毒锡还原剂的半氢化反应。
An Efficient Microwave-Promoted Route to (Z)-Stilbenes from trans-Cinnamic Acids: Synthesis of Combretastatin A-4 and Analogues
cis-Stilbenes were synthesized from trans-cinnamic acids, involving ethylenic-bond bromination and a subsequent one-pot microwave-promoted stereoselective debrominative decarboxylation-Suzuki cross-coupling strategy. This sequence represents a useful way to prepare a variety of combretastatin A-4 derivatives.
Synthesis and biological evaluation of thiophene and benzo[b]thiophene analogs of combretastatin A-4 and isocombretastatin A-4: A comparison between the linkage positions of the 3,4,5-trimethoxystyrene unit
Combretastatin A-4 and isocombretastatin A-4 derivatives having thiophenes or benzo[b]thiophenes instead of the B ring were prepared and evaluated for their in cellulo tubulin polymerization inhibition (TPI) and antiproliferative activities. The presence of the benzo[b]thiophene ring proved to have a crucial effect as most of the thiophene derivatives, except those having one methoxy group, were inactive to inhibit tubulin polymerization into microtubules. The influence of the attachment position was also studied: benzo[b]thiophenes having iso or cis 3,4,5-trimethoxystyrenes at position 2 were 12-30-fold more active than the 3-regioisomers for the TPI activity. Some of the novel designed compounds exhibited interesting anti-proliferative effects on two different cell lines. (C) 2015 Elsevier Ltd. All rights reserved.