THE ISOLATION OF NOVEL DITERPENOIDS, INCLUDING A C-40 BIS-DITERPENOID, FROM THE BRAZILIAN PLANT VELLOZIA-MAGDALENAE (VELLOZIACEAE)

Two new diterpenoid acids, magdalenic acid (1), and an unusual bis-dit erpenoid diacid, bismagdalenic acid (2), have been isolated from the h exane extract of the Brazilian plant Vellozia magdalenae (Velloziaceae ). Magdalenic acid is a regular diterpenoid of the uncommon eunicellan class, while bismagdalenic acid (2) is a bis-diterpene diacid apparen tly formed via a Diels-Alder type condensation of magdalenic acid and cis-ozic acid, a regular labdane diterpenoid. The structures of the ne w compounds were established by comprehensive spectral analysis. This is the first report of the isolation of the more commonly marine eunic ellan class diterpene from a terrestrial plant, and the first report o f these structural classes of diterpenoids from this chemically-prolif ic family of plants. (C) 1997, Elsevier Science Ltd.