Fluorinated benzofuro[2,3-b]pyridines, benzothieno[2,3-b]pyridines and 9H-pyrido[2,3-b]indoles (α-carbolines) were synthesized via regiospecific pyridine core annulation of a number of fluoro-containing 1,3-CCC-dielectrophiles to benzofuran-2-amine, benzothiophen-2-amine and 1H-indol-2-amine. Based on the 2,4-bis(trifluoromethyl)-9H-pyrido[2,3-b]indole thus synthesized, the preparative approach towards a set of nucleosides and nucleoside mimetics bearing the α-carboline framework was elaborated.
合
氟苯并呋喃[2,3-b]
吡啶、
苯并噻吩[2,3-b]
吡啶和9H-
吡啶[2,3-b]
吲哚(α-卡宾)通过多种含
氟的1,3-CCC-双电亲体与
苯并呋喃-2-胺、
苯并噻吩-2-胺和1H-
吲哚-2-胺进行区域选择性的
吡啶核心环化反应合成。基于所合成的2,4-二(三
氟甲基)-9H-
吡啶[2,3-b]
吲哚,进一步阐述了制备一系列具有α-卡宾结构的核苷和核苷类似物的方法。