Excavatoids E and F: Discovery of Two New Briaranes from the Cultured Octocoral Briareum excavatum

Two new briarane-related diterpenoids, designated as excavatoids E (1) and F (2), were isolated from the cultured octocoral Briareum excavatum. The structures of compounds 1 and 2 were established on the basis of extensive spectral data analysis. Briaranes 1 and 2 were found to exhibit moderate inhibitory effects on elastase release by human neutrophils

Discovery of New Eunicellins from an Indonesian Octocoral Cladiella sp.

Two new 11-hydroxyeunicellin diterpenoids, cladieunicellin F (1) and (–)-solenopodin C (2), were isolated from an Indonesian octocoral Cladiella sp. The structures of eunicellins 1 and 2 were established by spectroscopic methods, and eunicellin 2 was found to be an enantiomer of the known eunicellin solenopodin C (3). Eunicellin 2 displayed inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils. The previously reported structures of two eunicellin-based compounds, cladielloides A and B, are corrected in this study

Excavatoids O and P, New 12-Hydroxybriaranes from the Octocoral Briareum excavatum

Two new 12-hydroxybriarane diterpenoids, designated as excavatoids O (1) and P (2), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1 and 2 were established on the basis of extensive spectral data analysis. Excavatoid P (2) is the first metabolite which possesses a 6β -chlorine atom in briarane analogues

Cembranoids with 3,14-Ether Linkage and a Secocembrane with Bistetrahydrofuran from the Dongsha Atoll Soft Coral Lobophytum sp.

Four new cembranoids, lobophylins A–D (1–4), and one novel secocembrane, lobophylin E (5) were isolated from a soft coral Lobophytum sp. The structures of new metabolites were elucidated on the basis of extensive spectroscopic methods. Among these metabolites, 1–4 are rarely found cembranoids possessing a tetrahydrofuran moiety with a 3,14-ether linkage. In addition, 5 is the first secocembrane possessing two tetrahydrofuran moieties with 3,14- and 4,7-ether linkages

Lobocrassins A–E: New Cembrane-Type Diterpenoids from the Soft Coral Lobophytum crassum

Five new cembrane-type diterpenoids, lobocrassins A–E (1–5), were isolated from the soft coral Lobophytum crassum. The structures of cembranes 1–5 were established by spectroscopic and chemical methods and by comparison of the spectral data with those of known cembrane analogues. Lobocrassin A (1) is the first cembranoid possessing an α-chloromethyl-α-hydroxy-γ-lactone functionality and is the first chlorinated cembranoid from soft corals belonging to the genus Lobophytum. Lobocrassins B (2) and C (3) were found to be the stereoisomers of the known cembranes, 14-deoxycrassin (6) and pseudoplexaurol (7), respectively. Lobocrassin B (2) exhibited modest cytotoxicity toward K562, CCRF-CEM, Molt4, and HepG2 tumor cells and displayed significant inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils

Menelloides C and D, New Sesquiterpenoids from the Gorgonian Coral Menella sp

Two new metabolites, including a lindenane-type sesquiterpenoid, menelloide C (1), and a germacrane-type sesquiterpenoid, menelloide D (2), were isolated from a Formosan gorgonian coral identified as Menella sp. The structures of 1 and 2 were established by spectroscopic methods and 2 displayed a weak inhibitory effect on the release of elastase by human neutrophils

Carijoside A, a Bioactive Sterol Glycoside from an Octocoral Carijoa sp. (Clavulariidae)

A new bioactive sterol glycoside, 3β-O-(3′,4′-di-O-acetyl-β-d-arabinopyranosyl) -25ξ-cholestane-3β,5α,6β,26-tetrol-26-acetate) (carijoside A, 1), was isolated from an octocoral identified as Carijoa sp. The structure of glycoside 1 was established by spectroscopic methods and by comparison with spectral data for the other known glycosides. Carijoside A (1) displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils and this compound exhibited moderate cytotoxicity toward DLD-1, P388D1, HL-60, and CCRF-CEM tumor cells

Natural Product Chemistry of Gorgonian Corals of Genus Junceella—Part II

The structures, names, bioactivities, and references of 81 new secondary metabolites obtained from gorgonian corals belonging to the genus Junceella are described in this review. All compounds mentioned in this review were obtained from sea whip gorgonian corals Junceella fragilis and Junceella juncea, collected from the tropical and subtropical Indo-Pacific Ocean

Nardosinane-Type Sesquiterpenoids from the Formosan Soft Coral Paralemnalia thyrsoides

Five new nardosinane-type sesquiterpenoids, paralemnolins Q–U (1–5), along with three known compounds (6–8), were isolated from the Formosan soft coral Paralemnalia thyrsoides. The structures of new metabolites were elucidated on the basis of extensive spectroscopic methods, and the absolute configuration of 1 was determined by the application of Mosher’s method on 1. Among these metabolites, 1 and 3 are rarely found nardosinane-type sesquiterpenoids, possessing novel polycyclic structures. Compounds 1, 3, 6 and 7 were found to possess neuroprotective activity

Cladielloides A and B: New Eunicellin-Type Diterpenoids from an Indonesian Octocoral Cladiella sp

Two new eunicellin-type diterpenoids, cladielloides A (1) and B (2), which were found to possess a 2-hydroxybutyroxy group in their structures, were isolated from an Indonesian octocoral identified as Cladiella sp. The structures of eunicellins 1 and 2 were elucidated by spectroscopic methods. Cladielloide B (2) exhibited moderate cytotoxicity toward CCRF-CEM tumor cells and this compound displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils