Exploring QSAR of Flavonoids as Scavengers of Peroxynitrite Using Electrotopological State (E-State) Atom Parameter

Peroxynitrite scavenging activity of eighteen substituted flavonoid derivatives was subjected to classical quantitative structure activity relationship ( QSAR) analysis using electrotopological state (E-state) atom parameter. For the development of the QSAR models, statistical techniques like stepwise multiple linear regression and partial least squares (PLS) were used. Based on the internal validation and external prediction statistics stepwise (Q(2) = 0.842) and PLS ( R 2 pred = 0.614) methods were found to the best models, respectively. The equations also satisfy the F-max criteria suggested by Livingstone and Salt. All the models indicate the impact of the phenyl ring at position 2. Proper positioning of hydroxyl group in the phenyl ring is important for activity. Based on the findings, the models show the utility of E-state parameters in QSAR study for better understanding about the contribution of atoms or fragments in the molecules towards the biological activity.