Design, Synthesis, and Molecular Modeling Studies of Novel Coumarin Carboxamide Derivatives as eEF-2K Inhibitors

Abstract

Eukaryotic elongation factor-2 kinase (eEF-2K) is an unusual alpha kinase commonly upregulated in various human cancers, including breast, pancreatic, lung, and brain tumors. We have demonstrated that eEF-2K is relevant to poor prognosis and shorter patient survival in breast and lung cancers and validated it as a molecular target using genetic methods in related <i>in vivo</i> tumor models. Although several eEF-2K inhibitors have been published, none of them have shown to be potent and specific enough for translation into clinical trials. Therefore, development of highly effective novel inhibitors targeting eEF-2K is needed for clinical applications. However, currently, the crystal structure of eEF-2K is not known, limiting the efforts for designing novel inhibitor compounds. Therefore, using homology modeling of eEF-2K, we designed and synthesized novel coumarin-3-carboxamides including compounds <b>A1</b>, <b>A2</b>, and <b>B1-B4</b> and evaluated their activity by performing <i>in silico</i> analysis and <i>in vitro</i> biological assays in breast cancer cells. The Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) area results showed that <b>A1</b> and <b>A2</b> have interaction energies with eEF-2K better than those of <b>B1-B4</b> compounds. Our <i>in vitro</i> results indicated that compounds <b>A1</b> and <b>A2</b> were highly effective in inhibiting eEF-2K at 1.0 and 2.5 μM concentrations compared to compounds <b>B1-B4</b>, supporting the <i>in silico</i> findings. In conclusion, the results of this study suggest that our homology modeling along with <i>in silico</i> analysis may be effectively used to design inhibitors for eEF-2K. Our newly synthesized compounds <b>A1</b> and <b>A2</b> may be used as novel eEF-2K inhibitors with potential therapeutic applications.