Isolation of gallic acid esters as antiplasmodial constituents of Swintonia foxworthyi (Anacardiaceae).

An extract of a leaf and twig sample from Swintonia foxworthyi demonstrated weak in vitro activity against two clones of Plasmodium falciparum. At the same time, the extract was inactive in cancer cell cytotoxicity assays. Bioassay-directed fractionation led to the isolation of methyl gallate as the principal antiplasmodial constituent; the compound demonstrated estimated IC(50) values of 2.0 and 3.5 μg/ml against the W2 and D6 clones of P. falciparum, respectively. Methyl digallate was also isolated from an active fraction and demonstrated estimated IC(50) values of 4.6 and 5.3 μg/ml against the W2 and D6 clones, respectively. Copyright © 1997 Gustav Fischer Verlag. Published by Elsevier GmbH.. All rights reserved.