EIGHT NEW XENIA DITERPENOIDS FROM THREE SOFT CORALS OF THE RED SEA

Article abstract of DOI:10.1016/S0040-4020(01)91590-X

Investigation of the terpenoid content of three soft corals from the Gulf of Eilat (THe Red Sea), Xenia macrospiculata, X. obscuronata and X. lilielae resulted in the isolation of 8 new diterpens.Two of the new compounds belong to the xeniolides (xenialactol-D (10a) and xeniolide-E (13)) and the other six (4,14-diepoxyxeniaphyllene (15), 4,5-epoxyxeniaphyllan-14,15-diol (17), 4,14-diepoxy-xeniaphyllenol-A (21a), xeniaphyllenol-B (23a), xeniaphyllenol-C (24a) and xeniaphyllantriol (25) are new xeniaphyllanes (prenylated caryophyllanes).The structure determination of the various compounds is based on chemical transformations as well as on the 1H and 13C NMR spectra.Several known caryophyllene derivatives have been synthesised for 13C NMR spectra and chemical comparisons.The 13C NMR has proven to be an excellent probe for structural and stereochemical determinations.