A simple sensitive spectrophotometric method was developed using Phenolic compounds. The method is based on the reaction of the secondary amine as n-electron donor with the π-acceptor 2,3,5,6-tetra chloro 1,4-benzo quinone. The coloured charge-transfer complex was measured at 412nm. The Free radical generation was confirmed with the polymerization of acrylonitrile with charge transfer complex as initiator. The procedure was applied successfully to the determination of the Free radical Scavenging activity of the title compounds. Among the Sixteen analogs, V16 exhibited highest antioxidant activity and very low IC50 value, V6 exhibited least antioxidant activity with highest IC50 value. In the present study, Quantitative Structure-activity relationship modeling was performed on a series of Phenolic derivatives. IP, EN, Soft and EI are found to be the explainable variables for the semi empirical methods. The statistical parameters from the models indicate that the data well fitted and have high predictive ability. The external predictive capability of the established model was evaluated by test set of 16 compounds. It is recommended that the bulky electron-donation groups at the R1 and R3 position can increase the biological activities of the inhibitors. It is expected that the developed model could provide some useful information for the future synthesis of highly potent Transferase inhibitor.