Tricycloalternarene derivatives from endophytic fungus Alternaria tenuissima SY-P-07.

A new tricycloalternarene, TCA 11a (1), was isolated from the culture broth of an endophytic fungus, Alternaria tenuissima SY-P-07, along with four known structurally related compounds 2-5. The structure of compound 1 was elucidated by extensive spectroscopic methods, especially 2D NMR, and the absolute stereochemistry of 1 was suggested on the basis of the CD spectral analysis and NOESY data.