Charge delocalization in Z-isomers of (4α → 6″, 2α → O → 1″)-phenylflavans with R = H, OH and OCH3. Effects on bond dissociation enthalpies and ionization potentials

► Hyperconjugative interactions as an important factor in understanding the associated values of BDEs and IPs. ► Enhanced free radical scavenging ability with R = OH can be related to specific charge delocalization effects. ► Even when flavans are nonplanar structures, our results show that the ring B is not independent of ring A. ► Charge delocalization mechanisms that define the interaction between A, D and B rings, are characterized and quantified.