A DFT study on the structural, electronic properties and radical scavenging mechanisms of calycosin, glycitein, pratensein and prunetin

► The BDE value clearly indicates the importance of 'B' ring. ► The trend of BDE and PDE is similar for the target molecules except for glycitein. ► SPLET in water and HAT in gas phase are found to be the most probable processes. ► The antioxidant mechanism of the pratensein is similar to genistein. ► High spin density appears on the 5-OH pratensein radical.