Alkaloids and a flavonoid from aerial parts (leaves and twigs) of Duguetia furfuracea - annonaceae

Abstract

ABSTRACT - Duguetia furfuracea is a shrub of the Annonaceae family that occurs in several regions in Brazil. In the state of Mato Grosso do Sul this species often becomes an invading plant when the cerrado is turned into pastures. In the local folk medicine, its powdered seeds are mixed with water and used against pediculosis, and the infusion of twigs and leaves is used to treat rheumatism.. The present work led to the isolation and characterization from the aerial parts of the plant (leaves and twigs), of twelve isoquinoline alkaloids of aporphine oxoaporphine, bisbenzyltetrahydro-isoquinoline, benzyltetrahydro-isoquinoline and tetrahydroprotoberberine skeletons. In addition b-sytosterol and the flavonoid isorhamnethin were obtained. The activity of these different patterns of isoquinoline skeleton and the flavonoid was tested against Trypanosoma cruzi, and only aporphinoid skeleton with (R)-configuration, (-)-asimilobine, was really effective against trypomastigotes (strain Y), killing approximately 72% of the parasites at a maximal concentration of 128.0 mM (IC50 57.2 mM). The trypanocidal activity of the alkaloids and the flavonoid have been investigated.