SEVERAL NEW ISOPRENOIDS FROM THE SOFT CORAL SINULARIA-ERECTA

Eight compounds were isolated from the Indo-Pacific soft coral Sinular ia erecta (Tixier-Durivault, 1945) collected from the lagoon of Mayott e, Comoros Islands, northwest of Madagascar. Four of the compounds, na mely the sesquiterpene germacrene D, the diterpenoids nephthenol and d ecaryiol, and norcembrene, are known. The other four are the new secon dary metabolites germacrene E (1), epi-norcembrene (3), and two bis-pu kalide diterpenes, mayotolides A and B (4 and 5). The structure of eac h of the compounds was determined by means of 1D and 2D NMR and MS spe ctroscopy in addition to some chemical transformations.