Isolation and relative stereochemistry of lippialactone, a new antimalarial compound from Lippia javanica.

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 chloroquine-sensitive 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 (13)C chemical shift calculations.