Antiprotozoal activity of flavonoid glycosides isolated from Clidemia sericea and Mosquitoxylon jamaicense

A new O-galloyl-C-glycosylflavone, 2 '',6 ''-O-digalloylvitexin (1), along with four known glycosylflavones (2 -5) have been isolated from Clidemia sericea D. Don (Melastomataceae), and four other known glycosylflavones (6 -9) have been isolated from Mosquitoxylon jamaicense Krug & Urb. (Anacardiaceae). Compound 1, 3, and 6 showed mild antimalarial activity (24 +/- 1, 38 +/- 2, and 44 +/- 1 mu M, respectively) against a chloroquine-resistant P. falciparum strain. Additionally, tests against leishmaniasis and Trypanosoma cruzi were made. These compounds were identified by MS, UV, IR, and 1D and 2D NMR data and by comparison with the literature data.