New 5-alkylpyrrole-2-carboxaldehyde derivatives from the sponge Mycale tenuispiculata.

The sponge Mycale tenuispiculata afforded three new compounds-(6'Z)-5-(23'-cyano-6'-tricosenyl)pyrrole-2-carboxaldehyd e (1), mycaleoxime (2), and (6'E)-5-(6'-penta decenyl)pyrrole-2-carboxaldehyde (3)-and three known compounds, 3-formyl indole, an admixture of 5-alkyl pyrrole-2-carboxaldehydes, and thymidine. The structures of the above compounds were elucidated by the interpretation of their spectral data.