New Halimane Diterpenoids from Croton oblongifolius - Roengsumran, Sophon; Pornpakakul, Surachai; Muangsin, Nongnuj; Sangvanich, Polkit; Nhujak, Thumnoon; Singtothong, Pravit; Chaichit, Narongsak; Puthong, Songchan; Petsom, Amorn (Planta Medica, 2004)