The Discovery of Novel Antimalarial Aminoxadiazoles as a Promising Nonendoperoxide Scaffold

Since the appearance
of resistance to the current front-line antimalarial
treatments, ACTs (artemisinin combination therapies), the discovery
of novel chemical entities to treat the disease is recognized as a
major global health priority. From the GSK antimalarial set, we identified
an aminoxadiazole with an antiparasitic profile comparable with artemisinin
(1), with no cross-resistance in a resistant strains
panel and a potential new mode of action. A medicinal chemistry program
allowed delivery of compounds such as 19 with high solubility
in aqueous media, an acceptable toxicological profile, and oral efficacy.
Further evaluation of the lead compounds showed that in vivo genotoxic
degradants might be generated. The compounds generated during this
medicinal chemistry program and others from the GSK collection were
used to build a pharmacophore model which could be used in the virtual
screening of compound collections and potentially identify new chemotypes
that could deliver the same antiparasitic profile.