Synthesis of Isoxazolopyridines and Spirooxindoles under Ultrasonic Irradiation and Evaluation of Their Antioxidant Activity

New polycyclic-fused isoxazolo[4,5-e] pyridines and spirooxindoles were obtained via multicomponent reaction of 5-amino-3-methylisoxazole, indan-1,3-dione, and aromatic aldehydes and reaction of 5-amino-3-methylisoxazole, isatin, and beta-diketones in the presence of (+/-)-camphor-10-sulfonic acid as an effective and nontoxic organocatalyst under ultrasound-promoted conditions. The antioxidant activity of the novel synthesized compounds was studied.Kirklareli UniversityKirklareli University [KLUBAP 015]This study was financially supported by Kirklareli University under Project no. KLUBAP 015. The author thanks Assistant Professor Dr. Melek Gul, Associate Professor Dr. Emine Bagdatli, and Assistant Professor Dr. Aliye Gediz Erturk for their guidance and helpful comments on antioxidant activity assays