Monoindole Alkaloids from a Marine Sponge Spongosorites sp.

Seven (1–7) monoindole derivatives were isolated from the MeOH extract of a marine sponge Spongosorites sp. by bioactivity-guided fractionation. The planar structures were established on the basis of NMR and MS spectroscopic analyses. Compounds 1–5 are unique indole pyruvic acid derivatives. Compounds 1–2 and 4–6 are isolated for the first time from a natural source although they were previously reported as synthetic intermediates. Compound 3 was defined as a new compound. Co-occurring bisindoles such as hamacanthins and topsentins might be biosynthesized by condensation of two units of these compounds. The compounds were tested for cytotoxicity against a panel of five human solid tumor cell lines, and compound 7 displayed weak activity

Synthesis and Reactivity of Oxazinoindolones via Regioselective 6- exo-dig Iodolactonization Reaction

International audienceAn efficient protocol for facile construction of 3,4-dihydro-10-iodo-3-iodomethylene-[1,4]-oxazino[4,3-a]indol-1-ones has been developed by using a regio-and stereoselective iodolactonization reaction. Subsequent palladium cross-coupling reactions of 3,4-dihydro-10-iodo-3-iodomethylene-[1,4]-oxazino[4,3-a]indol-1-ones readily afforded functionalized oxazinoindolones