Novel antimalarial chloroquine- and primaquine-quinoxaline 1,4-di-N-oxide hybrids: Design, synthesis, Plasmodium life cycle stage profile, and preliminary toxicity studies

European Journal of Medicinal Chemistry
2018.0

Abstract

Emergence of drug resistance and targeting all stages of the parasite life cycle are currently the major challenges in antimalarial chemotherapy. Molecular hybridization combining two scaffolds in a single molecule is an innovative strategy for achieving these goals. In this work, a series of novel quinoxaline 1,4-di-N-oxide hybrids containing either chloroquine or primaquine pharmacophores was designed, synthesized and tested against both chloroquine sensitive and multidrug resistant strains of Plasmodium falciparum. Only chloroquine-based compounds exhibited potent blood stage activity with compounds 4b and 4e being the most active and selective hybrids at this parasite stage. Based on their intraerythrocytic activity and selectivity or their chemical nature, seven hybrids were then evaluated against the liver stage of Plasmodium yoelii, Plasmodium berghei and Plasmodium falciparum infections. Compound 4b was the only chloroquine-quinoxaline 1,4-di-N-oxide hybrid with a moderate liver activity, whereas compound 6a and 6b were identified as the most active primaquine-based hybrids against exoerythrocytic stages, displaying enhanced liver activity against P. yoelii and P. berghei, respectively, and better SI values than primaquine. Although both primaquine-quinoxaline 1,4-di-N-oxide hybrids slightly reduced the infection of mosquitoes, they inhibited sporogony of P. berghei and compound 6a showed 92% blocking of transmission. In vivo liver efficacy assays revealed that compound 6a showed causal prophylactic activity affording parasitaemia reduction of up to 95% on day 4. Absence of genotoxicity and in vivo acute toxicity were also determined. These results suggest the approach of primaquine-quinoxaline 1,4-di-N-oxide hybrids as new potential dual-acting antimalarials for further investigation.

Knowledge Graph

Similar Paper

Novel antimalarial chloroquine- and primaquine-quinoxaline 1,4-di-N-oxide hybrids: Design, synthesis, Plasmodium life cycle stage profile, and preliminary toxicity studies
European Journal of Medicinal Chemistry 2018.0
Primaquine–pyrimidine hybrids: Synthesis and dual-stage antiplasmodial activity
European Journal of Medicinal Chemistry 2015.0
Novel 4-Aminoquinoline-Pyrimidine Based Hybrids with Improved in Vitro and in Vivo Antimalarial Activity
ACS Medicinal Chemistry Letters 2012.0
Synthesis and antimalarial activity of new heterocyclic hybrids based on chloroquine and thiazolidinone scaffolds
Bioorganic & Medicinal Chemistry 2011.0
Synthesis, characterization and antimalarial activity of quinoline–pyrimidine hybrids
Bioorganic & Medicinal Chemistry 2013.0
Antimalarial and anti-inflammatory activities of new chloroquine and primaquine hybrids: Targeting the blockade of malaria parasite transmission
Bioorganic & Medicinal Chemistry 2020.0
Anti- Plasmodium falciparum activity of quinoline–sulfonamide hybrids
Bioorganic & Medicinal Chemistry 2015.0
Design and synthesis of quinoline-pyrimidine inspired hybrids as potential plasmodial inhibitors
European Journal of Medicinal Chemistry 2021.0
Novel Endoperoxide-Based Transmission-Blocking Antimalarials with Liver- and Blood-Schizontocidal Activities
ACS Medicinal Chemistry Letters 2014.0
N-Substituted aminoquinoline-pyrimidine hybrids: Synthesis, in vitro antimalarial activity evaluation and docking studies
European Journal of Medicinal Chemistry 2019.0