Cytotoxic constituents of Polyalthia longifolia var. pendula.

A new halimane diterpene, 3β,5β,16α-trihydroxyhalima-13(14)-en-15,16-olide (1), and a new oxoprotoberberine alkaloid, (−)-8-oxopolyalthiaine (2), along with 20 known compounds, were isolated from a methanolic extract of Polyalthia longifolia var. pendula. The structures of compounds 1 and 2 were established by spectroscopic analysis. Several of these compounds were evaluated for cytotoxicity toward a small panel of human cell lines.