Design, synthesis, and biological evaluation of thieno[2,3- d ]pyrimidine-based isoxazole derivatives as potential antimicrobial and anticancer agents: In vitro and in silico insights

This work the design, and synthesis of thieno[2,3-d]pyrimidine-based isoxazole derivatives (4a–4j) are reported along with characterization with the support of 1H NMR,13C NMR, HRMS spectral techniques. The compounds were investigated for their antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and antifungal activity (Escherichia coli and Pseudomonas aeruginosa). They were also carried out molecular docking and MTT assay against MCF-7 breast cancer cells containing estrogen receptor alpha (ERα) (PDB ID: 3POZ). The compound (4b) exhibited effective docking scores as well as potent microbial activity against Gram-positive bacteria but displayed moderate activity against MCF-7 in the MTT assay. The anti-cancer activity of the synthesized compounds (4b, 4h, and 4j), which revealed good binding affinity in a docking study, was tested against MCF-7 (human Caucasian breast adenocarcinoma) via primary and secondary screening.