Synthesis, molecular modeling and bioactivity of new bis-thiazole, thiazole-pyrazole, and thiazole-pyridine analogues
Abrar Bayazeed, Rua B. Alnoman, Kahdr Alatawi, Omar M. Alatawi, Alaa M. Alqahtani, Mariam Mojally, Noof A. Alenazi, Nashwa M. El‐Metwaly
Abstract
Several new thiazole derivatives linked pyrazole and/or pyridine rings were synthesized based on the versatile precursor 2-(5-acetyl-4-methyl-3-phenylthiazol-2(3H)-ylidene)acetonitrile (1). The synthesized derivatives were optimized using DFT approach in order to inspect the configurations and energies of the HOMO-LUMO orbitals. The data disclosed low energy gap (ΔEH-L), 0.99–2.54 eV, following the order 9 < 3 = 4 ≈ 2 ≈ 8 < 5 < 1 < 7 ≈ 6. The in vitro anticancer activity of the new thiazole hybrids was tested against three cancer cell lines (HepG2, HCT-116, and MCF-7) as well as standard fibroblast cells (WI38) using Doxorubicin as a reference drug. The thiazole-pyridine hybrids 8 and 9 exhibited high cytotoxic efficacies against the MCF-7 cell line, IC50 28.53 ± 0.39 and 25.47 ± 0.54 µM. Moreover, the synthesized hybrids were docked against the crystal structure of (PDB: 3rcd) as a representative protein for the human epidermal growth factor receptor (HER2) to approve the relationship between the in vitro cytotoxicity results and inhibitor binding interactions. The docking study showed that thiazole-pyridine hybrids 8 and 9 displayed the highest score of bindings, which was compatible with the results of the cytotoxicity results.