Trypargine alkaloids from a previously undescribed Eudistoma sp. ascidian.

The MeOH extract of an undescribed Eudistoma sp. ascidian was found to contain the known beta-carboline trypargine (3); the two novel trypargine derivatives trypargimine (4) and 1-carboxytrypargine (5); and 3',5'-dibromo-4'-methoxyphenethylamine (6). The structures of the novel trypargine derivatives were elucidated through the use of mass spectrometry and NMR. The trypargine isolated in this study was found to be nearly racemic in contrast to the previously described isolate which was chiroptically pure. Other previously described compounds detected in the MeOH extract include 4-hydroxyphenylacetamide, tryptamine, 1,3,7-trimethylguanine, and tetrahydropentoxyline (7).