Triterpenoid constituents of Raulinoa echinata.

A phytochemical investigation of the stems of the South Brazilian endemic species Raulinoa echinata has led to the isolation of two new methoxylated protolimonoid epimers (1 and 2) together with the known melianone and melianodiol. The leaves afforded three glabretal-type triterpene derivatives esterified by N-methylanthranilic acid (3-5). Compounds 1 and 2 displayed weak inhibitory activity when assayed in vitro against trypomastigote forms of Trypanosoma cruzi. Compounds 1-5 were inactive in a brine shrimp (Artemia salina) lethality test.