Four new bioactive lobane diterpenes of the soft coral Lobophytum pauciflorum from Mindoro, Philippines

Edrada-Ebel, Ruangelie and Proksch, P and Wray, V and Witte, L and van Ofwegen, L (1998) Four new bioactive lobane diterpenes of the soft coral Lobophytum pauciflorum from Mindoro, Philippines. Journal of Natural Products, 61 (3). pp. 358-361. ISSN 0163-3864

Full text not available in this repository.Request a copy from the Strathclyde author

Abstract

The marine soft coral Lobophytum pauciflorum collected from Mindoro Island, Philippines, yielded four new lobane diterpene derivatives: the acetate congeners of epoxylobatrienol and lobatrienediol (2 and 7, respectively), a methoxyl congener of lobatetraene (10), and an oxepin congener of lobatrienetriol (11), and six known derivatives (1, 3-6, and 8). The structures of the new compounds were unambiguously established on the basis of NMR spectroscopic (1H, 13C, COSY, 1H-detected direct, and long-range 13C-1H correlations) and mass spectrometric (EIMS) data. All of the compounds were active against the phytopathogenic fungus Cladosporium cucumerinum. Compound 1 was found to be active against the Gram-positive bacteria Bacillus subtilis and the yeast Saccharomyces cerevisiae. The isolated lobane diterpenes were also active in the brine shrimp lethality test. In the latter bioassay, compounds 8 and 10 were the most active congeners with LC50's of 0.64 and 4.18 micrograms/mL, respectively.