Xanthones from the seeds of Allanblackia monticola and their apoptotic and antiproliferative activities.

Phytochemical investigations of the seeds of ALLANBLACKIA MONTICOLA have led to the isolation and characterization of one new xanthone derivative, named allanxanthone E ( 1), together with seven known compounds, including five xanthones, 1,7-dihydroxy-3-methoxy-2-(3-methylbut-2-enyl)xanthone ( 2), alpha-mangostin ( 3) , garciniafuran ( 4) , allanxanthone C ( 5), and 1,6-dihydroxy-2,4-diprenylxanthone ( 6), and two pentacyclic triterpenes, friedelin and lupeol. The structures of these compounds were established on the basis of one- and two-dimensional NMR homo- and heteronuclear correlation evidence. Some of these compounds were evaluated for their apoptotic and antiproliferative activities against human leukemic B lymphocytes, such as the hairy cell leukemia-derived ESKOL cell line and cells from B-CLL (B-cell chronic lymphocytic leukemia) patients.