The aerial parts of Lippia javanica were investigated for biologically active chemical compounds
present in them. Chromatographic separation of the ethyl acetate extract of the aerial parts yielded
a new antimalarial α-pyrone, lippialactone (2). Lippialactone is active against the chloroquinesensitive
D10 strain of Plasmodium falciparum with an IC50 value of 9.1 μg/mL, and is also mildly
cytotoxic. The relative stereochemistry of lippialactone was determined by molecular modeling
based on the determination of the relative configuration by quantum mechanical GIAO 13C
chemical shift calculations.