Synthesis of 2-Acylbenzo[<i>b</i>]thiophenes via Cu-Catalyzed α-C–H Functionalization of 2-Halochalcones Using Xanthate
作者:Subramani Sangeetha、Govindasamy Sekar
DOI:10.1021/acs.orglett.7b00462
日期:2017.4.7
An efficient protocol is described for the synthesis of 2-acylbenzo[b]thiophenes from easily accessible 2-iodochalcones through α-C–H functionalization using Cu(OAc)2 catalyst and xanthate as sulfur source. Less reactive 2-bromochalcones also yielded the corresponding 2-acylbenzothiophenes in good yield. The reaction proceeds via in situ incorporation of sulfur followed by copper-catalyzed cyclization
描述了一种有效的规程,用于使用Cu(OAc)2催化剂和黄原酸酯作为硫源,通过α-C–H官能化,从易于获得的2-碘对二苯并呋喃中合成2-酰基苯并[ b ]噻吩。反应性较低的2-溴查耳酮也以良好的产率产生相应的2-酰基苯并噻吩。该反应通过硫的原位结合进行,然后进行铜催化的环化反应,生成没有外部酰基源的2-酰基苯并噻吩。合成的重要性通过1-(5-羟基苯并噻吩-2-基)乙酮的合成得到了展示,这是一种已知的mRNA前剪接调节剂。
Copper-catalyzed double C–S bond formation for the synthesis of 2-acyldihydrobenzo[<i>b</i>]thiophenes and 2-acylbenzo[<i>b</i>]thiophenes
作者:Subramani Sangeetha、Govindasamy Sekar
DOI:10.1039/d0cc04647g
日期:——
An efficient domino process is developed for the synthesis of diversely substituted 2,3-dihydrobenzo[b]thiophenes from 2-iodoketones using a Cu-catalyst and easily available xanthate as a sulfur surrogate in good yields. This domino method has been expanded for the synthesis of 2-acylbenzo[b]thiophenes using in situ generated iodine (I2) from by-product KI in high yields. Treatment of xanthate with
开发了一种有效的多米诺方法,该方法使用铜催化剂和易于获得的黄原酸酯作为硫代用品,以高收率从2-碘酮合成各种取代的2,3-二氢苯并[ b ]噻吩。该多米诺法已得到扩展,可利用副产物KI的原位生成的碘(I 2)高产率地合成2-酰基苯并[ b ]噻吩。用铜(II)催化剂处理黄药可能将其还原为铜(I)催化剂,从而启动催化循环。根据XPS分析,碘色测试和其他几个对照实验的结果,提出了一种可能的机制。
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.
Substituted 2-(3′,4′,5′-trimethoxybenzoyl)-benzo[b]thiophene derivatives as potent tubulin polymerization inhibitors
作者:Romeo Romagnoli、Pier Giovanni Baraldi、Maria Dora Carrion、Olga Cruz-Lopez、Manlio Tolomeo、Stefania Grimaudo、Antonietta Di Cristina、Maria Rosaria Pipitone、Jan Balzarini、Andrea Brancale、Ernest Hamel
DOI:10.1016/j.bmc.2010.05.068
日期:2010.7
The central role of microtubules in cell division and mitosis makes them a particularly important target for anticancer agents. On our early publication, we found that a series of 2-(3',4',5'-trimethoxybenzoyl)-3-aminobenzo[b]thiophenes exhibited strong antiproliferative activity in the submicromolar range and significantly arrested cells in the G2-M phase of the cell cycle and induced apoptosis. In order to investigate the importance of the amino group at the 3-position of the benzo[b] thiophene skeleton, the corresponding 3-unsubstituted and methyl derivatives were prepared. A novel series of inhibitors of tubulin polymerization, based on the 2-(3,4,5-trimethoxybenzoyl)-benzo[b] thiophene molecular skeleton with a methoxy substituent at the C-4, C-5, C-6 or C-7 position on the benzene ring, was evaluated for antiproliferative activity against a panel of five cancer cell lines, for inhibition of tubulin polymerization and for cell cycle effects. Replacing the methyl group at the C-3 position resulted in increased activity compared with the corresponding 3-unsubstituted counterpart. The structure-activity relationship established that the best activities were obtained with the methoxy group placed at the C-4, C-6 or C-7 position. Most of these compounds exhibited good growth inhibition activity and arrest K562 cells in the G2-M phase via microtubule depolymerization. (C) 2010 Elsevier Ltd. All rights reserved.