Limonoids from the endemic Brazilian species Raulinoa echinata

Phytochemical survey of stems and leaves of the South Brazilian endemic Rau linoa echinata Cowan, Rutaceae led to the isolation of five limonoid deriva tives: the widespread limonin, limonexic acid, kihadalactone B, a methoxyla ted limonexic acid derivative and a degraded limonoid structurally related to fraxinellone. The two latter compounds have been isolated for the first time. These compounds displayed weak inhibitory activity when assayed in vi tro against trypomastigote forms of Trypanosoma cruzi. In this paper, the i solation, structure elucidation and bioactivity of these compounds are repo rted.