New conjugates of substituted 1,2,3-triazoles
linked to 1,2,4-triazoles
were synthesized starting from the appropriate S-propargylated 1,2,4-triazoles 7 and 8. Ligation of 1,2,4-triazoles to the 1,2,3-triazole
core was performed through Cu(I)-catalyzed cycloaddition of 1,2,4-triazole-based
alkyne side chain 7 and/or 8 with several
un/functionalized alkyl- and/or aryl-substituted azides 9–15 to afford the desired 1,4-disubstituted 1,2,3-triazoles 16–27, using both classical and microwave methods. After their spectroscopic
characterization (infrared, 1H, 13C nuclear
magnetic resonance, and elemental analyses), an anticancer screening
was carried out against some cancer cell lines including human colon
carcinoma (Caco-2 and HCT116), human cervical carcinoma (HeLa), and
human breast adenocarcinoma (MCF-7). The outcomes of this exploration
revealed that compounds 17, 22, and 25 had a significant anticancer activity against MCF-7 and
Caco-2 cancer cell lines with IC50 values of 0.31 and 4.98
μM, respectively, in relation to the standard reference drug,
doxorubicin. Enzyme-docking examination was executed onto cyclin-dependent
kinase 2; a promising aim for cancer medication. Synthesized compounds
acquiring highest potency showcased superior interactions with the
active site residue of the target protein and exhibited minimum binding
energy. Finally, the density functional theory (DFT) calculations
were carried out to confirm the outcomes of the molecular docking
and the experimental findings. The chemical reactivity descriptors
such as softness (δ), global hardness (η), electronegativity
(χ), and electrophilicity were calculated from the levels of
the predicted frontier molecular orbitals and their energy gap. The
DFT results and the molecular docking calculation results explained
the activity of the most expectedly active compounds 17, 22, and 25.