unprecedented radical difluoromethylarylation reaction of alkynes has been developed by discovering a new difluoromethylation reagent, CF2HSO2NHNHBoc. This air-stable and solid reagent can be prepared in one step from commercially available reagents CF2HSO2Cl and NH2NHBoc. The CF2H radical, generated through ferrocene-mediated electrochemical oxidation, participates in an unexplored alkyne addition reaction
A novel highly efficient, environmentally benign Lewis acid‐catalyzed, and protection‐free protocol for the construction of valuable polycyclic products bearing a 1H‐pyrrolo[1,2‐a]indole scaffold is described, starting from readily available propargylic alcohols and 2‐ethynylanilines. The one‐pot transformation entails the cleavage of one C−O bond, and the construction of two C−N bonds and one C−C
描述了一种新型的高效,环境友好的路易斯酸催化且无保护的方案,用于构建带有1 H-吡咯并[1,2- a ]吲哚骨架的有价值的多环产物,从容易获得的炔丙醇和2开始乙炔基苯胺。一锅转换需要裂解一个C-O键,两个C-N键和一个C-C双键。这种独特的操作简单的方法是在温和条件下和空气中进行的,产生的水是唯一的副产物。它具有可伸缩性,并显示出良好的功能组兼容性和广泛的适用范围。
Copper-Catalyzed Trifluoromethylation/Cyclization of Alkynes for Synthesis of Dioxodibenzothiazepines
作者:Zi-Qi Zhang、Yi-Hao Xu、Jing-Cheng Dai、Yan Li、Jie Sheng、Xi-Sheng Wang
DOI:10.1021/acs.orglett.1c00344
日期:2021.3.19
A facile and efficient approach for the synthesis of the CF3-containing dioxodibenzothiazepines has been developed via copper-catalyzed trifluoromethylation/cyclization of alkynes utilizing a radical relay strategy. This method has demonstrated low catalyst loading, high regiocontrol, and broad scope under mild conditions. Good compatibility for the N-protecting group, gram-scale experiment, and further
A simple and mild photoredox catalytic approach to access difluoroalkylated dioxodibenzothiazepines in high regioselectivity via radical cascadecyclization has been described herein. In contrast to previous methods, this strategy does not involve the use of transition-metal catalysts and avoids the potential disadvantages of inevitable toxicity and the tedious removal process of metal catalysts. The
tuberculosis (Mtb), resulting in superior anti-tuberculosis (TB) activity. Compared to the corresponding ‘open-form’ ethyl benzofuran-3-carboxylates, the enhanced anti-TB effects seen with the conformationally restricted coumestan series could be attributed to the extra π-π stacking interactions between the benzene ring of coumestans and the phenyl ring of F1670 residue located in the Pks13-TE binding
我们之前报道了一系列香豆素——一种含有δ-内酯的天然四环支架——可有效靶向结核分枝杆菌( Mtb )中聚酮合酶 13 (Pks13) 的硫酯酶结构域,从而产生优异的抗结核 (TB) 活性。与相应的“开放式”苯并呋喃-3-羧酸乙酯相比,构象受限的香豆素系列增强的抗结核作用可归因于香豆素的苯环和苯环之间额外的 π-π 堆积相互作用位于 Pks13-TE 结合域的 F1670 残基。为了进一步探索这种结合特征,合成了新的四环类似物并评估了它们对Mtb的抗结核活性菌株 H 37 Rv。“开放形式”类似物与四环对应物的初步比较再次表明后者在抗结核活性方面更胜一筹。特别是含有 δ-内酰胺的 5 H - benzofuro [3,2 - c ]quinolin-6-ones 给出了最有希望的结果。化合物65显示出对Mtb H 37 Rv 的有效活性,MIC 值介于 0.0313 和 0.0625 μg/mL