%0 Journal Article
%T Hydrazonophenol, a Food Vacuole-Targeted and Ferriprotoporphyrin IX-Interacting Chemotype Prevents Drug-Resistant Malaria
%J -
%D 2019
%R https://doi.org/10.1021/acsinfecdis.8b00178
%X The rapid emergence of resistance against frontline antimalarial drugs essentially warrants the identification of new-generation antimalarials. Here, we describe the synthesis of (E)-2-isopropyl-5-methyl-4-((2-(pyridin-4-yl)hydrazono)methyl)phenol (18), which binds ferriprotoporphyrin-IX (FeIII-PPIX) (Kd = 33 nM) and offers antimalarial activity against chloroquine-resistant and sensitive strains of Plasmodium falciparum in vitro. Structure¨Cfunction analysis reveals that compound 18 binds FeIII-PPIX through the £¿C¨TN¨CNH¨C moiety and 2-pyridyl substitution at the hydrazine counterpart plays a critical role in antimalarial efficacy. Live cell confocal imaging using a fluorophore-tagged compound confirms its accumulation inside the acidic food vacuole (FV) of P. falciparum. Furthermore, this compound concentration-dependently elevates the pH in FV, implicating a plausible interference with FeIII-PPIX crystallization (hemozoin formation) by a dual function: increasing the pH and binding free FeIII-PPIX. Different off-target bioassays reduce the possibility of the promiscuous nature of compound 18. Compound 18 also exhibits potent in vivo antimalarial activity against chloroquine-resistant P. yoelii and P. berghei ANKA (causing cerebral malaria) in mice with negligible toxicity
%U https://pubs.acs.org/doi/10.1021/acsinfecdis.8b00178