Synthesis of Substituted α-Carboline Derivatives by Base-Mediated Annulation of Azaindoles with Alkylidene Malononitriles

Abstract A new synthetic method has been established to synthesize α-carbolines through the reaction of electrophilic azaindoles with ambiphilic alkylidene malononitriles. The versatility of this approach was explored by using various alkylidene malononitriles, and also by conducting nitrogen migration on the azaindole. This method enables the simultaneous introduction of diverse functional groups, such as amine, nitrile, and aryl, onto the benzene ring of a carboline scaffold. As the scaffold putatively shows antiproliferative and other biological activities, the method is valuable in the development of new chemical entities for drug discovery.