One-pot three-component synthesis of thioether linked 4-hydroxycoumarin-benzothiazole derivatives under ambient condition and evaluation of their biological activity

•Coumarin derivatives were synthesized using L-proline catalyst.•The synthesized compounds exhibited promising antioxidant activity.•Screened for their cytotoxic activity against HePG2 cells.•Coumarin derivatives showed good antimycobacterial activity against H37Rv strain.•In silico Molecular docking studies was carried out with GlcN-46-P synthase receptor. An efficient and convenient method has been outlined for the synthesis of 3-[(1,3-benzothiazol-2-ylsulfanyl)(phenyl)methyl]-2H-chromen-4-ol derivatives via a one-pot three-component Knoevenagel condensation reaction between 4-hydroxycoumarin, substituted aldehyde, and 2-mercapto benzothiazole in the presence of 10 mol% L-proline as an efficient catalyst in ethanol. The structure of all the newly synthesized chromone derivatives was confirmed by different spectroscopic techniques like IR, 1H NMR, 13C NMR, and LC-MS. Further, all the derivatives were screened for their biological activities such as anti-mycobacterial activity, in vitro antioxidant activity, anticancer activity, and molecular docking studies.