Synthesis and in vitro antioxidant activity of quinolin-5-ylamine derivatives

Imines of six new quinolin-5-ylamine derivatives 3(a-c) and 5(a-c) were synthesized by the reaction of quinolin-5-ylamine (1) with different aldehydes 2(a-c) and ketones 4(a-c). The chemical structures of the compounds were confirmed by UV-visible, FT-IR and 1H NMR spectral study. New compounds were screened for the antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) method. Butylated Hydroxytoluene (BHT) was used as standard. All the compounds showed DPPH radical scavenging activity, where compound 3c was the best radical scavenger.