Chemical investigation of an antimalarial Chinese medicinal herb Picrorhiza scrophulariiflora

An antimalarial medicinal plant Picrorhiza scrophulariiflora was chemically investigated as part of our ongoing research in traditional chinese medicines (TCM). Mass directed fractionation of the active part of the crude extract led to the isolation of ten main components, three new compounds (1–3) and seven known compounds (4–10). Compound 10 inhibited the growth of the Plasmodium falciparum 3D7 malarial parasite line, with an IC₅₀ value of 8.3 μM. This compound accounted for ～95% of P. falciparum growth inhibitory activity in the crude extract confirming, for this TCM, that a single compound was responsible for the antimalarial activity.