New tetrazole fused imidazopyridine derivatives (12a–j) were developed to exploit their cytotoxic activity towards cancer cell lines-MCF7, A549, and MDA-MB-231, utilizing MTT reduction assay with doxorubicin as standard drug. The compounds 12 h and 12j demonstrated strong anticancer activity bearing IC50 values 1.44 μM and 1.33 μM against A549 cell line.

Design, synthesis and biological studies of tetrazole fused imidazopyridines
    Abstract
        Graphical abstract
    1 Introduction
    2 Results and discussion
        2.1 Chemistry
        2.2 Biological evaluation—in vitro cytotoxicity
        2.3 Molecular docking studies of phosphatidylinositol 3-kinases (PI3Kα) with tetrazole fused imidazopyridine derivatives
    3 Experimental section
        3.1 General
        3.2 2-(4-Bromophenyl)H-imidazo[1,2-a]pyridine-3-carbaldehyde (8)
        3.3 (2-(4-Bromophenyl)H-imidazo[1,2-a]pyridin-3-yl)methanol (9)
        3.4 3-(Azidomethyl)-2-(4-bromophenyl)H-imidazo[1,2-a]pyridine (10)
        3.5 2-(4-Bromophenyl)-3-((5-phenyl-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a]pyridine (12a)
        3.6 2-(4-Bromophenyl)-3-((5-(3,4,5-trimethoxyphenyl)-1H-tetrazol-1-yl)methyl)H-imidazo [1,2-a]pyridine (12b)
        3.7 2-(4-Bromophenyl)-3-((5-(4-methoxyphenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a] pyridine (12c)
        3.8 2-(4-Bromophenyl)-3-((5-(4-chlorophenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a] pyridine (12d)
        3.9 2-(4-Bromophenyl)-3-((5-(4-bromophenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a]py ridine (12e)
        3.10 2-(4-Bromophenyl)-3-((5-(4-fluorophenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a] pyridine (12f)
        3.11 2-(4-Bromophenyl)-3-((5-(4-nitrophenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a]pyr idine (12g)
        3.12 2-(4-Bromophenyl)-3-((5-(3-nitrophenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a] pyridine (12h)
        3.13 2-(4-Bromophenyl)-3-((5-p-tolyl-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a]pyridine (12i)
        3.14 2-(4-Bromophenyl)-3-((5-(4-(trifluoromethyl)phenyl)-1H-tetrazol-1-yl)methyl)H-imidazo[1,2-a]pyridine (12j)
        3.15 MTT assay
        3.16 Docking studies
    4 Conclusion
    References

• Banoth Reddy(Department of Chemistry, Krishna University, Machilipatnam, Andhra Pradesh 521003, India)
• Amit Kumar Taneja(Department of Chemistry, Chaudhary Charan Singh University, Meerut 250001, India)
• Mandava Bhuvan Tej(Department of Healthcare Informatics, Sacred Heart University, 5151 Park Avenue, Fair Fields, CT 06825, USA)
• Komati Navya Sri(Department of MBBS, NRI Academy of Medical Sciences, Chinakakani, Guntur, Andhra Pradesh 522503, India)
• Mandava Bhagya Tej(Department of MBBS, NRI Academy of Medical Sciences, Chinakakani, Guntur, Andhra Pradesh 522503, India)
• Suryadevara Vijayavardhini(Department of Chemistry, Amrita Sai Institute of Science and Technology, Paritala, Andhra Pradesh 521180, India)
• Dandamudi Srilaxmi(Department of Chemistry, Dhanekula Institute of Engineering and Technology, Ganguru, Vijayawada, Andhra Pradesh 521139, India)
• Somasekhar Tiruveedhula(Department of Science & Humanities, St. Martin’s Engineering College, Dhulapally, Hyderabad, Telangana 500100, India)
• Srinivasa Rao Penumutchu(Department of Chemistry, Case Western Reserve University, Cleveland, USA)
• Mandava V. Basaveswara Rao(Department of Chemistry, Krishna University, Machilipatnam, Andhra Pradesh 521003, India) Corresponding author