ANTIMALARIAL ACTIVITY AND NUCLEOSIDE TRANSPORT INHIBITORY ACTIVITY OFTHE TRITERPENIC CONSTITUENTS OF CIMICIFUGA SPP

The in vitro antimalarial activity against human malaria parasite (Pla smodium falciparum, FCR-3 strain) was examined using 59 triterpenoids obtained during studies on the triterpenic constituents of Cimicifuga spp. The 50% effective concentration values (EC50) of 25 active triter penoids were 1.0-3.0 mu M, and 19 of the compounds had a common 16, 23 :23, 26:24, 25-triepoxy group in the side-chain moieties. Among the ac tive triterpenoids, 9 also showed significant inhibition of nucleoside transport in mouse splenocytes. A relationship between the antimalari al activity and the inhibition of nucleoside transport involving these triterpenoids is discussed.