Synthesis of 1,8-naphthyridines: a recent update (microreview)

This microreview focuses on the recent achievements (2015–2019) toward the synthesis of 1,8-naphthyridines, which include multicomponent reactions, Friedlander approach using green strategy, hydroamination of terminal alkynes followed by Friedlander cyclization, metal-catalyzed synthesis, and ring expansion reaction of 3-substituted 1H-pyrrolo[2,3-b]pyridin-2(3H)-one.