Microwave-assisted synthesis, antioxidant and antimicrobial evaluation of 2-indolinone-based bis-1,2,3-triazole derivatives

A series of 2-indolinone-based bis-1,2,3-triazole derivatives have been synthesized in excellent yields via microwave-assisted, copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) reaction of O-, N-propargylated indolinone derivatives with in situ generated organic azides. The antioxidant activity of the synthesized compounds was evaluated by DPPH, NO and radical scavenging methods. Among the compounds screened for antioxidant activity, compounds 5e, 5f and 5o showed excellent radical scavenging activity more than the standard drugs ascorbic acid and BHT. The synthesized compounds were evaluated for their antimicrobial activity against gram-positive and gram-negative bacterial and fungal strains. Compounds 5g, 5h, 5n, 5q and 5r were found to be the most promising microbial growth inhibitory molecules.