Revision of the absolute configuration at C(23) of lanostanoids and isolation of secondary metabolites from formosan soft coral Nephthea erecta.

Three new oxygenated ergostanoids, 1-3, one known ergostanoid, 4, one new trinoreudesmadienone, 5, one new calamenene type sesquiterpene, 6, and one known aristolane-type sesquiterpene, (-)-aristolone (7), have been isolated from the AcOEt extract of the soft coral Nephthea erecta. The structures of these compounds were determined by extensive spectroscopic and X-ray crystallographic analysis, as well as Mosher's method. We revised the absolute configuration at C(23) in the side chain of some lanostanoids as a result of the Mosher's products of 1 (i.e., 1a and 1b). The cytotoxicities against selected cancer cells and the anti-inflammatory effects of these tested metabolites 1-7 were determined in vitro.

Cytotoxic xenia diterpenoids from the soft coral Xenia umbellata.

Eleven new xenia diterpenoids, umbellacins A-G (1-7), 14,15-epoxy-xeniolide H (8), 3-acetyl-14,15-epoxy-xeniolide H (9), and umbellacins H and I (10, 11), were isolated from a methylene chloride-soluble fraction of the soft coral Xenia umbellata. The structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Sesquiterpenoids and norsesquiterpenoids from the Formosan soft coral Lemnalia laevis.

Eight new nornardosinane sequiterpenoids, laevinols A-H (1-8), a new neolemnane sesquiterpenoid, laevinone A (9), and the previously known 6beta-acetyl-4beta,5beta-dimethyl-1(10)alpha-epoxy-2beta-hydroxy-7-oxodecalin (10) and 11,12-dihydroxy-6,10-eremophiladiene (11) were isolated from the methylene chloride solubles of the Formosan soft coral Lemnalia laevis. Their structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Xenia diterpenoids from the formosan soft coral Xenia blumi.

Eight new xenia diterpenoids, blumiolide-A (1) (novel carbon skeleton), blumiolide-B (2), 9-deoxy-isoxeniolide-A (3), 9-deoxy-7,8-epoxy-isoxeniolide-A (4), 9-deacetoxy-7,8-epoxy-13-epi-xenicin (5), 9-deoxy-7,8-epoxy-xeniolide-A (6), blumiolide-C (7), and blumicin-A (8), were isolated from the methylene chloride solubles of the Formosan soft coral Xenia blumi. Their structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Xenibellols A and B, new diterpenoids from the formosan soft coral Xenia umbellata.

Xenibellols A (1) and B (2), possessing an unprecedented diterpenoid skeleton, were isolated from the soft coral Xenia umbellata. The structures of xenibellols A and B were established by extensive analysis of spectroscopic data.

Prenylbicyclogermacrane diterpenoids from the formosan soft coral Nephthea pacifica.

Ten new prenylbicyclogermacrane diterpenoids, pacificins A-J (1-10), were isolated from the methylene chloride solubles of the Formosan soft coral Nephthea pacifica. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Steroids and sesquiterpenoids from the soft corals Dendronephthya gigantea and Lemnalia cervicorni.

One new cytotoxic steroid, dendronesterone A (1), two new steroids, dendronesterones B and C (2 and 3), and a known steroid (4) were isolated from the methylene chloride solubles of the Formosan soft coral Dendronephthya gigantea. Two cytotoxic ylangene-type sesquiterpenoids, lemnalol (5) and the new compound cervicol (6), as well as two ylangene-type sesquiterpenoids, isolemnalol (7) (a new compound) and 4-oxo-alpha-ylangene (8), were isolated from the methylene chloride solubles of the Formosan soft coral Lemnalia cervicorni. Their structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

New nardosinanes and 19-oxygenated ergosterols from the soft coral Nephthea armata collected in Taiwan.

Five new nardosinane sesquiterpenoids, armatins A-E, lemnal-1(10)-ene-2,12-dione (a new natural product), and two new cytotoxic 19-oxygenated ergosterols, armatinols A and B, were isolated from the methylene chloride extract of the soft coral Nephthea armata, collected in Taiwan. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity was determined against selected cancer cells.

New diterpenoids from Viburnum awabuki.

Eight new vibsane-type diterpenoids, vibsanins P-W (1-8), were isolated from the methanol extracts of the leaves and twigs of Viburnum awabuki. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Triterpenoids from Parthenium argentatum x P. tomentosa.

Four tetracyclic triterpenoids and lupeol were isolated from the hybrid Parthenium argentatum x P. tomentosa. The new triterpenoids were identified as 16, 24-epoxy-3 alpha-hydroxylanost-8-ene (argentatin E); 16, 24-epoxy-25-hydroxycycloart-1, 11, 22-trien-3-one (argentatin F); 16,24-dihydroxycycloart-20, 25-dien-3-one (argentatin G) and 16, 24-dihydroxycycloart-25-en-3-one (argentatin H). The chemical identities of these compounds were confirmed by the different spectrometric measurements.