Two new Aspera chaetominines A and B, and a new derivative of terrein, isolated from marine sponge associated fungus Aspergillus versicolour SCSIO XWS04 F52

Two new alkaloids, Aspera chaetominines A (1) and B (2), a new derivative (3) of terrein, and together with 11 known compounds (4-14) were isolated from marine sponge Callyspongia sp. -derived fungus Aspergillus versicolour SCSIO XWS04 F52, which was identified on the basis of morphology and ITS sequence analysis. The planar structures of 1-3 were determined by spectroscopic (1H, 13C NMR, HSQC, HMBC, and 1H-1H COSY), and MS analysis. Compounds 1 and 2 showed cytotoxic activity against leukaemia K562 and colon cancer cells SW1116 with IC50 7.5 to 12.5 μM, and also compounds 1 and 2 exhibited significant protection against H1N1 virus-induced cytopathogenicity in MDCK cells with IC50 values of 15.5 and 24.5 μM, respectively.