Open AccessSynthesis of New 4-Aminoquinolines and Evaluation of Their In Vitro Activity against Chloroquine-Sensitive and Chloroquine-Resistant Plasmodium falciparum
Author(s) -
C. S. K. Rajapakse,
Maryna Lisai,
Christiane Deregnaucourt,
Véronique Sinou,
Christine Latour,
Dipankar Roy,
Joseph Schrével,
Roberto A. SánchezDelgado
Publication year - 2015
Publication title -
hal (le centre pour la communication scientifique directe)
Language(s) - English
DOI - 10.1371/journal.pone.0140878.s004
Subject(s) - chloroquine , plasmodium falciparum , aminoquinolines , in vitro , malaria , pharmacology , virology , biology , chemistry , immunology , combinatorial chemistry , biochemistry
International audienceThe efficacy of chloroquine, once the drug of choice in the fight against Plasmodium falcipa-rum, is now severely limited due to widespread resistance. Amodiaquine is one of the most potent antimalarial 4-aminoquinolines known and remains effective against chloroquine-resistant parasites, but toxicity issues linked to a quinone-imine metabolite limit its clinical use. In search of new compounds able to retain the antimalarial activity of amodiaquine while circumventing quinone-imine metabolite toxicity, we have synthesized five 4-amino-quinolines that feature rings lacking hydroxyl groups in the side chain of the molecules and are thus incapable of generating toxic quinone-imines. The new compounds displayed high in vitro potency (low nanomolar IC 50), markedly superior to chloroquine and comparable to amodiaquine, against chloroquine-sensitive and chloroquine-resistant strains of P. falcipa-rum, accompanied by low toxicity to L6 rat fibroblasts and MRC5 human lung cells, and metabolic stability comparable or higher than that of amodiaquine. Computational studies indicate a unique mode of binding of compound 4 to heme through the HOMO located on a biphenyl moeity, which may partly explain the high antiplasmodial activity observed for this compound