7--Substituted-3-oxadiazole Quinolones with Potent Antimalarial Activity Target the Cytochrome Complex.

The development of new antimalarials is required because of the threat of resistance to current antimalarial therapies. To discover new antimalarial chemotypes, we screened the Janssen Jumpstarter library against the asexual parasite and identified the 7--substituted-3-oxadiazole quinolone hit class. We established the structure-activity relationship and optimized the antimalarial potency.

Optimization of 2,3-Dihydroquinazolinone-3-carboxamides as Antimalarials Targeting PfATP4.

There is an urgent need to populate the antimalarial clinical portfolio with new candidates because of resistance against frontline antimalarials. To discover new antimalarial chemotypes, we performed a high-throughput screen of the Janssen Jumpstarter library against the asexual blood-stage parasite and identified the 2,3-dihydroquinazolinone-3-carboxamide scaffold. We defined the SAR and found that 8-substitution on the tricyclic ring system and 3-substitution of the exocyclic arene produced analogues with potent activity against asexual parasites equivalent to clinically used antimalarials.

Fast-Killing Tyrosine Amide (()-SW228703) with Blood- and Liver-Stage Antimalarial Activity Associated with the Cyclic Amine Resistance Locus (CARL).

Current malaria treatments are threatened by drug resistance, and new drugs are urgently needed. In a phenotypic screen for new antimalarials, we identified ()-SW228703 (()-SW703), a tyrosine amide with asexual blood and liver stage activity and a fast-killing profile. Resistance to ()-SW703 is associated with mutations in the cyclic amine resistance locus (CARL) and acetyl CoA transporter (ACT), similarly to several other compounds that share features such as fast activity and liver-stage activity.

Reaction hijacking of tyrosine tRNA synthetase as a new whole-of-life-cycle antimalarial strategy.

Aminoacyl transfer RNA (tRNA) synthetases (aaRSs) are attractive drug targets, and we present class I and II aaRSs as previously unrecognized targets for adenosine 5'-monophosphate-mimicking nucleoside sulfamates. The target enzyme catalyzes the formation of an inhibitory amino acid-sulfamate conjugate through a reaction-hijacking mechanism. We identified adenosine 5'-sulfamate as a broad-specificity compound that hijacks a range of aaRSs and ML901 as a specific reagent a specific reagent that hijacks a single aaRS in the malaria parasite , namely tyrosine RS (YRS).