Mannich bases of alizarin: synthesis and evaluation of antioxidant capacity

In this work, a series of C-3-aminomethyl derivatives based on alizarin (1) was obtained using Mannich reaction. The antioxidant properties of the compounds were evaluated using in vitro models. It was found that most of the synthesized derivatives were superior to alizarin (1) in radical scavenging activity and Fe2+-chelation ability. The antioxidant activity of alizarin derivatives was confirmed using biologically relevant test systems; all compounds strongly inhibited Fe2+/ascorbate-initiated oxidation of unsaturated fatty acids of animal lipids and most of them increased the survival of red blood cells under conditions of acute oxidative stress. In the cellular model system, the Mannich base containing a thiomorpholinomethyl moiety demonstrated the highest activity. [GRAPHICS] .

Automated summary

A series of C-3-aminomethyl derivatives based on alizarin were synthesized using Mannich reaction. The compounds exhibited superior radical scavenging activity and Fe2+-chelation ability compared to alizarin. They demonstrated significant antioxidant activity in biologically relevant test systems, including inhibition of lipid oxidation and protection of red blood cells under acute oxidative stress conditions. The Mannich base containing a thiomorpholinomethyl moiety showed the highest activity.