8. Synthesis of 6-azaindoles via formal electrophilic [4 + 1]-cyclization of 3-amino-4-methyl pyridines: new frontiers of diversity Sergey P. Ivonin,Volodymyr V. Voloshchuk,Eduard B. Rusanov,Sergiy Suikov,Serhiy V. Ryabukhin,Dmytro M. Volochnyuk Org. Chem. Front. 2024 11 2088