Aim: Synthesis of novel 2(2-hydroxyphenyl) pyrimidine/benzothiazole piperazinyl-substituted flavones end evaluate their antioxidant activity.
Results: Six novel 2-(2-hydroxyphenyl) pyrimidine/benzothiazole-substituted flavones were synthesized, their structures were confirmed by elementary and spectral analyses. The compounds were evaluated for their in vitro antioxidant potency by employing various antioxidant assays.
Conclusion: All tested compounds acted as scavengers of free radicals like hydroxyl (15-45%), 2,2-diphenyl-1-picrylhydrazyl• (17-48%) at 1.25 and 0.5 mM concentrations respectively. The total antioxidant status activity values of the compounds ranged from 234.1 to 464.1 μm trolox equivalent/g, the total antioxidant capacity - from 24.9 to 52.7 μm trolox equivalent per gram. Compounds incorporating the benzothiazole group on the piperazine ring were more effective antioxidants than those with the 2-(2-hydroxyphenyl) pyrimidine group.
Keywords: antioxidant activity; chemiluminescence; free radical inhibitory activity; piperazinyl flavone analogs; spectroscopy.