View of Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> supported vanillin/Indole-sulfonic acid as a green, sustainable and magnetically reusable catalyst for the synthesis of mono-, bis- and tris- azo acridines | Iranian Journal of Catalysis

← Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> supported vanillin/Indole-sulfonic acid as a green, sustainable and magnetically reusable catalyst for the synthesis of mono-, bis- and tris- azo acridines