Design, synthesis, biological evaluation and molecular docking study on peptidomimetic analogues of XK469.

XK469 is identified as a potent quinoxaline antineoplastic agent based on its significant clinical efficacy. It probably exerts its activity via DNA topoisomerase II (topo II) inhibition. To obtain more effective antineoplastic agents, a spectrum of peptidomimetic-type quinoxaline analogues of XK469 was herein designed, synthesized, and evaluated. Few compounds ( e.g . 13a and 13b ) exhibited obvious cytotoxicity indicated by in vitro anti-proliferative assay. SAR investigation revealed that introducing of hydrophobic tert -butylamine or dodecylamine moiety at the 3-position of quinoxaline core is favorable for achieving a better anti-proliferative potency, while peptidomimetic derivatives only yielded moderate cytotoxicity. Compounds with improved anti-proliferative activities also demonstrated decent anti-metastatic potencies comparable with that of doxorubicin (Doxo) based on in vivo mouse model study. The topo II-mediated kinetoplast DNA ( k DNA) decatenation assay as well as molecular docking studies implicated that these compounds tend to be potent topo II inhibitors. Overall, compounds 13a and 13b , 13b in particular, standed out from various assessments and might be promising candidates for further chemical optimization. [ABSTRACT FROM AUTHOR]