Synthesis and characterization of novel bioactive azo compounds fused with benzothiazole and their versatile biological applications

•The new heterocyclic azo compounds were synthesized via diazo-coupling reaction.•Structure of newly synthesized azo compounds was confirmed by various spectroscopic techniques.•Pharmacological properties were explored through in vitro antioxidant and antibacterial studies.•Biologically significance of azo compounds were ascertained by molecular docking, anticancer and cytotoxicity experiments. The present work established the synthesis of novel azo incorporated heterocyclic bioactive compounds (4a-4d)via diazo-coupling reaction between the 2-amino benzothiazole and various synthetic phenolic antioxidant molecules like BHA, phloroglucinal, 2,4-di‑tert-butylphenol and 2,6-di‑tert-butylphenol. The structure of newly synthesized azo compounds was confirmed by various spectroscopic techniques such as UV–Vis, FT-IR, 1H NMR, 13C NMR and LC-(ESI)MS while a single crystal X-ray structural analysis of the azo compound (4a) was carried out. Biological efficiency of novel azo compounds was evaluated by antioxidant activities like DPPH radical scavenging activity and reducing power activity which exhibits the azo compounds 4a and 4b possess potent antioxidant ability. The significant antibacterial activity also exposed by all newly synthesized azo compounds against human pathogenic organisms and often the remarkable activity also observed by 4a and 4b in all bacterial strain. In silico molecular docking study demonstrates the azo fused compounds owing several crucial interactions with EGFR protein. Moreover in vitro anticancer and toxicity of selected azo compounds were assessed by MTT cytotoxicity assay against lung cancer cell line (A549) and normal skin cell line (L929). [Display omitted]