Compared with peripheral late-stage transformations mainly focusing on carbon–hydrogen functionalizations, reliable strategies to directly edit the core skeleton of pharmaceutical lead compounds still remain scarce despite the recent flurry of activity in this area. Herein, we report the skeletal editing of indoles through nitrogen atom insertion, accessing the corresponding quinazoline or quinoxaline bioisosteres by trapping of an electrophilic nitrene species generated from ammonium carbamate and hypervalent iodine. This reactivity relies on the strategic use of a silyl group as a labile protecting group that can facilitate subsequent product release. The utility of this highly functional group-compatible methodology in the context of late-stage skeletal editing of several commercial drugs is demonstrated.
与主要侧重于碳-氢官能化的外围后期转化相比,直接编辑药物先导化合物核心骨架的可靠策略仍然稀缺,尽管最近该领域的活动十分活跃。在此,我们报告了通过氮原子插入对吲哚进行骨架编辑的方法,通过捕获由氨基甲酸铵和高价碘生成的亲电烯类,获得相应的喹唑啉或喹喔啉生物异构体。这种反应性依赖于战略性地使用硅烷基作为易溶保护基团,从而促进后续产物的释放。这种高度兼容官能团的方法在几种商业药物的后期骨架编辑中的应用得到了证实。