New Scalarane Class Sesterterpenes from an Indonesian Sponge, <i>Phyllospongia</i> sp.

A series of scalarane class sesterterpenes (1−8) have been isolated from an Indonesian sponge, Phyllospongia sp. Their structures were determined by spectroscopic analysis and confirmed by single-crystal X-ray diffraction on compound 1. The absolute stereochemistry of 1 was established by modified Mosher's method

Aromatic Cyclic Peroxides and Related Keto-Compounds from the <i>Plakortis</i> sp. Component of a Sponge Consortium

Six unreported aromatic compounds, 1−6, were isolated, along with the known compounds dehydrocurcuphenol and manoalide, from a sample of Plakortis sp., which was the main component of a Pacific sponge consortium. The new molecules were chemically characterized by spectroscopic methods. Compounds 1−4 contain a six-membered cyclic peroxide, whereas 5 and 6 display a terminal methyl ketone. The new metabolites were tested for antifungal and antibacterial properties. Compounds 1 and 4 were weakly active against S. aureus

Aaptamine Derivatives from the Indonesian Sponge <i>Aaptos suberitoides</i>

Four new aaptamine derivatives (<b>1</b>–<b>4</b><b></b>) along with aaptamine (<b>5</b>) and three related compounds (<b>6</b>–<b>8</b>) were isolated from the ethanol extract of the sponge <i>Aaptos suberitoides</i> collected in Indonesia. The structures of the new compounds were unambiguously determined by one- and two-dimensional NMR and by HRESIMS measurements. Compounds <b>3</b>, <b>5</b>, and <b>6</b> showed cytotoxic activity against the murine lymphoma L5178Y cell line, with IC₅₀ values ranging from 0.9 to 8.3 μM

Indoleamine 2,3-Dioxygenase Inhibitors Isolated from the Sponge <i>Xestospongia vansoesti</i>: Structure Elucidation, Analogue Synthesis, and Biological Activity

Two new IDO inhibitory meroterpenoids, xestolactone A (<b>1</b>) and xestosaprol O (<b>2</b>), have been isolated from the sponge <i>Xestospongia vansoesti</i>. Xestolactone A (<b>1</b>) has an unprecedented degraded meroterpenoid carbon skeleton. A short synthesis of the xestosaprol O (<b>2</b>) analogues <b>3</b> and <b>4</b> features the application of a rarely used photochemical coupling reaction. Synthetic analogue <b>3</b> is ∼40 times more potent than the inspirational natural product <b>2</b>

Twilight Zone Sponges from Guam Yield Theonellin Isocyanate and Psammaplysins I and J

From the organic extracts of two Guam sponges, <i>Rhaphoxya</i> sp. and <i>Suberea</i> sp., determined to have cytotoxic and chemopreventive activities, three new compounds, theonellin isocyanate (<b>1</b>) and psammaplysins I and J (<b>5</b>, <b>6</b>), and six previously reported compounds (<b>2</b>–<b>4</b>, <b>7</b>–<b>9</b>) were isolated and characterized spectroscopically (¹H and ¹³C NMR, MS, IR, UV, [α]_D). The two new metabolites (<b>5</b> and <b>6</b>) isolated from the <i>Suberea</i> sp. sponge are rare examples of compounds containing a bromotyramine moiety rather than the more usual dibromo analogue. For the compounds isolated from the <i>Rhaphoxya</i> sp., this is the first report of the known compounds <b>2</b>–<b>4</b> being found in a single sponge. For previously reported compounds <b>2</b>–<b>4</b> complete unambiguous ¹H and ¹³C NMR data are provided