12-hydroxy-E-gamma-bisabolene, a new sesquiterpene alcohol from a Caribbean sea whip of the genus Pseudopterogorgia (Gorgonacea, Cnidaria).

A new sesquiterpene alcohol, 12-hydroxy-E-gamma-bisabolene, is reported from an undescribed Caribbean sea whip of the genus Pseudopterogorgia. The structure of this new alcohol was established based upon spectral analyses and through chemical interconversions.

The pseudopterosins: anti-inflammatory and analgesic natural products from the sea whip Pseudopterogorgia elisabethae.

The Caribbean sea whip Pseudopterogorgia elisabethae (Octocorallia, Cnidaria) has been found to contain the pseudopterosins, a newly described class of natural products, which have been characterized as diterpene-pentoseglycosides. The pseudopterosins possess anti-inflammatory and analgesic properties that exceed, in our assays, the potencies of existing drugs such as indomethacin. As anti-inflammatory agents, the pseudopterosins appear to modify the arachidonic acid cascade by an as yet undefined mechanism of pharmacological action.

1H- and 13C-nmr assignments for taxol, 7-epi-taxol, and cephalomannine.

The 1H- and 13C-nmr spectra of taxol [1], 7-epi-taxol [2], and cephalomannine [3] were assigned using modern 1D and 2D nmr methods. Preliminary conformational information was obtained by nOe spectroscopy.

Taxus spp. needles contain amounts of taxol comparable to the bark of Taxus brevifolia: analysis and isolation.

New sources for the antitumor natural product taxol [1] are needed as demands for this promising cancer chemotherapeutic agent increase. Presently, supplies of taxol for clinical studies are obtained from the bark of Taxus brevifolia, a potentially limited source. Using analytical methods, the needles and stems of six Taxus species have been examined for taxol [1] and 10-deacetylbaccatin III [5], a related compound that can be converted to taxol through a semi-synthetic route. Amounts of taxol comparable to quantities reported from the bark of T. brevifolia were found in the needles of four of the Taxus species investigated. In addition, taxol was isolated from the needles of one Taxus species. Thus, Taxus needles may provide a renewable source of this valuable compound.

On the origin of terpenes in symbiotic associations between marine invertebrates and algae (zooxanthellae). Culture studies and an application of 13C/12C isotope ratio mass spectrometry.

13C/12C ratios of sets of compounds, algal sterols and terpenes, isolated from dinoflagellate symbiont (zooxanthellae)-bearing soft corals and gorgonians were determined. In most cases, a significant difference was found between the delta 13C values of the terpenes and of the algal sterols from the same set, the algal sterols containing less 13C than the terpenes. These results can only be explained if terpenes are synthesized by the host. Cultured zooxanthellae, isolated from symbiotic associations, do not make terpenes. Algal sterols of the various sets do not all have the same delta 13C value: average values range from -18.2 to -24.3%. A consistent difference of about 7% in the delta 13C values of sterols of cultured symbionts isolated from two of the gorgonians was found. This has potential applications for the taxonomy of zooxanthellae, most of which are believed by some specialists to be one discrete species.