Chemical constituents of Heteroplexis micocephala.

Eleven new compounds including two sesquiterpenes with an unusual 2,2,5,9-tetramethylbicyclo[6.3.0]undecane carbon skeleton (1 and 2), five phytane-type diterpene dilactones (3-7), an ent-clerodane diterpene dilactone (8), and three phenylpropenol esters (9-11), together with a diacylphenol (12) and 38 known compounds, have been isolated from an ethanolic extract of Heteroplexis micocephala. Their structures including absolute configurations were elucidated by spectroscopic and chemical analyses. In the in vitro assays, compound 6 showed a selective cytotoxic activity against A2780 with an IC(50) value of 4.37 microM, while sinapyl diangelate (13) showed a potent activity inhibiting HIV-1 replication with an IC(50) value of 4.04 microM.