(1H-Pyridin-4-ylidene)amines containing lipophilic side chains at the imine nitrogen atom were prepared as potential clopidol isosteres in the development of antimalarials. Their antiplasmodial activity was evaluated in vitro against the Plasmodium falciparum W2 (chloroquine-resistant) and FCR3 (atovaquone-resistant) strains. The most active of these derivatives, 4m, had an IC50 of 1 μM against W2 and 3 μM against FCR3. Molecular modeling studies suggest that (1H-pyridin-4-ylidene)amines may bind to the ubiquinol oxidation Qo site of cytochrome bc1.
Tiago Rodrigues a, Rita C. Guedes a, Daniel J. V. A. dos Santos a, Marta Carrasco a, Jiri Gut b, Philip J. Rosenthal b, Rui Moreira a, Francisca Lopes a
a iMed.UL, Faculty of Pharmacy, University of Lisbon, Av. Prof. Gama Pinto, 1649-003 Lisbon, Portugal
b Department of Medicine, San Francisco General Hospital, University of California, San Francisco, Box 0811, CA 94143, USA