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Updated: Jul 9, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Antimalarial quinolones: synthesis, potency, and mechanistic studies
Rolf W Winter1, Jane X Kelly, Martin J Smilkstein
1Biomedical Laboratory R&D Service, Mail Code: RD-33, Experimental Chemotherapy Laboratory, VA Medical Center, 3710 SW U.S. Veterans Hospital Road, Portland, OR 97239, USA.
Experimental Parasitology
|December 18, 2007
Summary
Novel quinolone derivatives show potent antiplasmodial activity against drug-resistant malaria strains. These compounds target the parasite cytochrome bc1 complex, offering potential new treatments for malaria.
Area of Science:
- Medicinal Chemistry
- Parasitology
- Drug Discovery
Background:
- Malaria remains a significant global health threat, with increasing drug resistance.
- Atovaquone targets the Plasmodium bc1 complex but faces resistance issues.
- Novel therapeutic agents are needed to combat resistant Plasmodium falciparum strains.
Purpose of the Study:
- To investigate the antiplasmodial activities of novel quinolone derivatives.
- To evaluate their efficacy against chloroquine-sensitive and resistant Plasmodium falciparum.
- To explore their mechanism of action, particularly targeting the cytochrome bc1 complex.
Main Methods:
- Synthesis and evaluation of quinolone derivatives with trifluoromethyl-terminated side chains.
- Determination of IC50 values against Plasmodium falciparum strains.
- Assessment of cross-resistance with atovaquone.
- Oxygen biosensor plate technology to measure inhibition of oxygen consumption.
Main Results:
- Quinolone derivatives exhibited IC50 values in the low nanomolar range (1.2–30 nM).
- Compounds showed activity against chloroquine-sensitive and multidrug-resistant strains.
- Evidence suggests targeting of the parasite cytochrome bc1 complex, similar to atovaquone.
- Inhibition of parasite oxygen consumption confirmed the mechanism of action.
Conclusions:
- Novel halogenated alkyl and alkoxy 4(1H)-quinolones demonstrate significant antiplasmodial potential.
- These "endochin-like quinolones" are effective against resistant malaria parasites.
- Further development could lead to new malaria therapeutics targeting the cytochrome bc1 complex.
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