Halisulfate 7, a new sesterterpene sulfate from a sponge, Coscinoderma sp

Isolation and characterization of antiplasmodial constituents from the marine sponge Coscinoderma sp

Six known compounds, namely two halisulfates 1 and 2 and four epidioxy sterols 3-6, were isolated from the marine sponge Coscinoderma sp. The structures of these compounds were confirmed by nuclear magnetic resonance (1H and 13C NMR) spectroscopy, and their antiplasmodial activities were determined against the chloroquine-resistant Dd2 strain of Plasmodium falciparum. The epidioxy steroids 3-6 all showed moderate to weak antiplasmodial activity, with IC50 values of 2.7 μM for (24S)-5α,8α-epidioxy-24-methylcholesta-6-en-3β-ol (3), 11.6 μM for 5α,8α-epidioxycholesta-6,24(28)-dien-3β-o1 (4), 2.33 μM for 5α,8α-epidioxy-24-methylcholesta-6,9(11)-24(28)-trien-3β-ol (5), and between 12 and 24 μM for 5α,8α-epidioxycholesta-6-en-3β-ol (6). In contrast, halisulfate 2 (1) was inactive, and halisulfate 1 (2) had an of IC50 value of about 24 μM.

Bioactive sulfated sesterterpene alkaloids and sesterterpene sulfates from the marine sponge Fasciospongia sp

Two new sulfated sesterterpene alkaloids, 19-oxofasciospongine A (3) and fasciospongine C (4), and a new sesterterpene sulfate, 25-hydroxyhalisulfate 9 (5), along with two known sesterterpene sulfates, halisulfates 7 (6) and 9 (7), were isolated from an organic extract of the marine sponge Fasciospongia sp. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectroscopic studies as well as by HRESIMS analysis. Compounds 1-7 exhibited inhibitory activity against Streptomyces 85E in the hyphae-formation inhibition assay. Compounds 1, 2, and 4-7 were not cytotoxic when tested at 20 microg/mL with MCF-7, LNCaP, and LU cell lines. Only compound 3 demonstrated a moderate cytotoxic effect on the MCF-7 (IC(50) 13.4 microM), LNCaP (IC(50) 21.8 microM), and LU-1 cells (IC(50) 5.0 microM), respectively.

Protein phosphatase inhibitors isolated from Spongia irregularis collected in Papua New Guinea

Irregularasulfate (1), a new nitrogen-containing sesterterpenoid, and the known sesterterpenoids hipposulfate C (2), halisulfate-7 (3), and igernellin (4), have been isolated from the marine sponge Spongia irregularis collected in Papua New Guinea. The structure of 1 was elucidated via analysis of its spectroscopic data. Sesterterpenoids 1, 2, and 3 are moderate inhibitors of the catalytic subunits of the mammalian Ser/Thr protein phosphatases calcineurin, PP-1, and PP-2A. The phosphate analogue of 3 and the thiophosphate analogue of 2 have been prepared from the corresponding natural products and evaluated for their ability to inhibit the phosphatase activity of calcineurin.

Marine natural products

This review covers the literature published in 2004 for marine natural products, with 693 citations (491 for the period January to December 2004) referring to compounds isolated from marine microorganisms and phytoplankton, green algae, brown algae, red algae, sponges, coelenterates, bryozoans, molluscs, tunicates and echinoderms. The emphasis is on new compounds (716 for 2004), together with their relevant biological activities, source organisms and country of origin. Biosynthetic studies (8), and syntheses (80), including those that lead to the revision of structures or stereochemistries, have been included.