Psorospermin, A New Antileukemic Xanthone From Psorospermum febrifugum

Abstract

An ethanolic extract of P. febrifugum was fractionated with antileukemic activity in vivo in the [mouse] P388 lymphocytic leukemia cells in mice and in vitro in the [human oral epidermoid carcinoma] KB cells. The new antileukemic xanthone psorospermin 1 was isolated and its structure elucidated. The chlorohydrin of O-methylpsorospermin 2 was isolated after treatment of the fraction containing psorospermin chlorohydrin 6 with diazomethane. Psorospermin 1 was demonstrated to have significant antitumor activity in the P388 in vivo system and cytotoxicity against the KB in vitro system.