Increased attention has been given to natural plants owing to several presumed health-promoting biological activities. Brassica oleracea var. Italica and their bioactive compounds exhibit health-promoting roles as well as antimicrobial, antioxidant, and anti-inflammatory properties. The aim of the study is used to confirm the mode of binding for antibacterial activity, elucidating quantum chemical properties, and ADME-drug-likeness of phenolic and flavonoids isolated from Brassica oleracea. L. Var. Italica. Methods: Docking studies were performed against 3AIC employing a flexible ligand docking approach using Autodock vina. SwissADME prediction and toxicology predictions were done using ADMET. The optimized structure and electrostatic potential of the isolated compounds were predicted by DFT analysis using B3LYP/31G basis levels. Results and discussion: Docking results revealed that Kaempferol and isochlorogenic acid showed better docking scores compared to other compounds. The SwissADME prediction results showed that kaempferol and isochlorogenic acid compounds satisfy Lipinski’s rule of five with zero violations having higher affinity value. Toxicological prediction results suggested that compounds are non-hepatotoxic, non-carcinogenic, non-irritant, immunogenic, and non-cytotoxic. The DFT analysis suggesting better bioactivity and chemical reactivity with considerable intra-molecular charge transfer between electron-donor to electron-acceptor groups. Conclusion: Kaempferol and isochlorogenic acid compound may serve as a lead molecule and further work is recommended for functional group inclusion, modification, and SAR study to develop novel antibacterial agents with therapeutic activity against S. mutans