The workflow of the study.

12,432 approved were docked into the active site of CDK6 using HTVS and XP docking modes of Glide resulting in 277 compounds with docking scores ≤7 kcal/mol. These compounds were then docked against aromatase and CDK4 enzymes using XP mode and their MM-GBSA was calculated. Four drugs showed good binding affinity to all three protein targets and favourable binding free energy with CDK6. Apomorphine displayed the most favorable binding free energy with all three protein targets and the stability of its interaction with CDK6 was proven via molecular dynamics simulation.