Chemical Investigation of two Antarctic Invertebrates, Synoicum adareanum (Chordata: Ascidiaceae; Enterogona; Polyclinidae) and Austrodoris kergulenensis (Molusca; Gastropoda; Nudibranchia; Dorididae)

Synoicum adareanum is a colonial tunicate commonly found on the benthos around Palmer Station on Anvers Island, Antarctica. A comprehensive chemical investigation of the lipophilic extract of the frozen tunicates gave a new series of polyketide macrolides, palmerolides A-E and H. The structure elucidation of these compounds was accomplished by extensive NMR and mass spectral studies.The palmerolides are unusual 20-membered macrolides displaying functionality more commonly found in sponges or cyanobacteria. Palmerolide A, the major member of the group, shows significant and selective in vitro cytotoxicity against melanoma with three orders of greater sensitivity relative to other cell lines tested, in the National Cancer Institute (NCI) 60 human cancer cell-line panel. In addition, it displays potent cytostatic activity against several other cancer cell lines. Based on NCI\u27s COMPARE analysis, palmerolide A was investigated as a V-ATPase inhibitor and shown to bind the V0 subunit with 2 nM inhibition.Austrodoris kerguelenensis is a common Antarctic nudibranch widely distributed in the High Antarctic and Sub Antarctic Zone. It is characterized by the presence of terpenoid glyceryl esters which are supposed to be involved in defense. Chemical investigations of several specimens of A. kerguelenensis collected near Palmer station Antarctica afforded hitherto undescribed series of clerodane diterpenoid glycerides. The structure elucidation of three major compounds of this series, palmadorin A, B and C was accomplished

Cytotoxin compounds and methods of isolation

The present invention concerns groups of compounds derived from tunicates of the Synoicum species, as well as to pharmaceutical compositions comprising these compounds, and uses thereof. Extracts from tunicates show selective toxicity against several different cancer cell lines in the NCI 60 cell line panel. These compounds are useful in the effective treatment of cancers, particularly malignant melanomas, colon cancer, and renal cancer cell lines

Cytotoxin compounds and methods of isolation

The present invention concerns groups of compounds derived from tunicates of the Synoicum species, as well as to pharmaceutical compositions comprising these compounds, and uses thereof. Extracts from tunicates show selective toxicity against several different cancer cell lines in the NCI 60 cell line panel. These compounds are useful in the effective treatment of cancers, particularly malignant melanomas, colon cancer, and renal cancer cell lines

Flabelliferins A and B, Sesterterpenoids from the South Pacific Sponge <i>Carteriospongia flabellifera</i>

Two new sesterterpenoids named flabelliferins A (<b>1</b>) and B (<b>2</b>) were isolated from the lipophilic extract of the sponge <i>Cateriospongia flabellifera,</i> collected in the South Pacific near Vanuatu. The structure and absolute configuration of these two compounds were assigned by a combination of one- and two-dimensional NMR spectroscopy and by Mosher’s ester analysis. Flabelliferin A (<b>1</b>) has a rare 25-homocheilanthane carbon skeleton, while flabelliferin B (<b>2</b>) is a 24-nor-25-homoscalarane sesterterpenoid

Inhibition of Hypoxia Inducible Factor‑2 Transcription: Isolation of Active Modulators from Marine Sponges

Renal or kidney cancer accounts for about 3% of all cancer cases reported each year in the U.S. Molecular signatures that define the cancer, such as the loss of functional VHL, are found in both sporadic and familial cases of cancer. In clear cell renal cancer, the transcription factor HIF-2α has been shown to have a distinct role in tumorigenesis. Our laboratories developed a cell-based screen to identify modulators of HIF-2α. Screening of the NCI’s Natural Product Extract Repository resulted in the identification of 10 sponge extracts, from which 12 compounds were isolated. The biological evaluation of these compounds will be discussed including evaluation of HIF-1α vs HIF-2α selectivity and the isolated compounds’ effects on mRNA from several pathways regulated by HIF