15-Deacetylsergeolide, a potent antileukemic quassinoid from Picrolemma pseudocoffea

Investigation of the leaf extract of Picrolemma pseudocoffea afforded a new antineoplastic quassinoid, 15-deacetylsergeolide (3), and two known quassinoids, isobruceine B (1) and sergeolide (2). The structure of 3, which displayed strong antileukemic activity in the P-388 test system, was established through the interpretation of spectral data and chemical correlation to 2.