作者:Thibault Gendron、Raul Pereira、Hafsa Y. Abdi、Timothy H. Witney、Erik Årstad
DOI:10.1021/acs.orglett.9b04280
日期:2020.1.3
Herein, we report that iron(II)/ammonium persulfate in aqueous acetonitrile mediates the Newman-Kwart rearrangement of O-aryl carbamothioates. Electron-rich substrates react rapidly under moderate heating to afford the rearranged products in excellent yields. The mild conditions, rapid reaction rates, and suitability for scale up offers immediate practical benefits to access functionalized thiophenols
Inverting the Selectivity of the Newman–Kwart Rearrangement via One Electron Oxidation at Room Temperature
作者:Stephan K. Pedersen、Anne Ulfkjær、Madeleine N. Newman、Sarangki Yogarasa、Anne U. Petersen、Theis I. Sølling、Michael Pittelkow
DOI:10.1021/acs.joc.8b01800
日期:2018.10.5
The discovery that the Newman–Kwartrearrangement can be performed at room temperature by action of a simple and readily available oxidant, cerium ammonium nitrate, is described. The conditions give clean conversion when using electron-rich aromatic substrates, and the reactions are often quantitative. Computational studies support a reaction mechanism where the O-thiocarbamate is first oxidized to
Design, synthesis and characterization of structurally dynamic cyclic <i>N</i>,<i>S</i>-acetals
作者:Emily K. Kirkeby、Andrew G. Roberts
DOI:10.1039/d0cc03503c
日期:——
We report the synthesis, characterization and comparison of a series of electronically perturbed, cyclic N,S-acetals. Inspired by electrophilic auxiliaries utilized for amine capture and concomitant peptide ligation, we studied these N,S-acetal systems and evaluated their propensity to generate zwitterionic intermediates in situ. Certain N,S-acetals in this study exhibit structurally dynamic properties
我们报告了一系列电子扰动的环状N , S-缩醛的合成、表征和比较。受用于胺捕获和伴随肽连接的亲电子助剂的启发,我们研究了这些N、S-缩醛系统并评估了它们原位生成两性离子中间体的倾向。本研究中的某些N , S -缩醛通过溶剂和 pH 依赖性在室温下通过C1-S 键电离开环和闭环的能力表现出结构动态特性。
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.