Artemisinin 's a drug used to treat multi-drug resistant strains of falciparum malaria. The compound (a sesquiterpene lactone)'s isolated from the plant Artemisia annua. Not all plants of this species contain artemisinin. Apparently it's only produced when the plant's subjected to certain conditions, most likely biotic or abiotic stress. It can be synthesized from artemisinic acid. The drug's derived from a herb used in Chinese traditional medicine, though it's usually chemically modified and c… (More on Artemisinin)