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

Abstract

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

Syntheses and biological studies of marine terpenoids derived from inorganic cyanide

“…An isolation effort from “twilight sponges”, isolated at depths below 50 m, produced a number of active extracts and resulting active compounds validating this unusual source material. xii These studies identified a new bisabolene derivative theonellin isocyanate 13 , as well the known isonitrile and isothiocyanate congeners. Other efforts obtained a variety of compounds in which the acyclic portion of the bisabolene scaffold is extensively oxidatively modified.…”

Cytotoxic Psammaplysin Analogues from a Suberea sp. Marine Sponge and the Role of the Spirooxepinisoxazoline in Their Activity

“…Chemical shifts are reported in ppm from tetramethylsilane with the solvent resonance resulting from incomplete deuteration as the internal references (acetone-d 6 : δ H 2.050 ppm). 13 C NMR spectra were recorded on a Varian Unity 500 (125 MHz) spectrometer with complete proton decoupling. Chemical shifts are reported in ppm from tetramethylsilane with the solvent as the internal reference (acetone-d 6 : δ C 206.68, 29.92 ppm).…”

Cytotoxic Psammaplysin Analogues from the Verongid Red Sea Sponge Aplysinella Species

“…Members of the order Verongiida are characterized by production of brominated compounds that are biosynthesized from bromotyrosine [1]. Compounds possessing the rare dibrominated 1,6-dioxa-2-azaspiro [4.6]undeca-2,7,9-triene moiety (spirooxepinisoxazoline) are derived from bromotyrosine and are named psammaplysins [2][3][4][5][6][7][8][9][10], ceratinamides [9,11] and ceratinadins [12]. Compounds with the spirooxepinisoxazoline moiety were reported mainly from members of the Verongiida [2][3][4][5][6][7][8][9][10]12] with only two representatives from the order Dictyoceratida [11,13].…”