Two new drimane sesquiterpenes, fudecadiones A and B, from the soil fungus Penicillium sp. BCC 17468.

Two new drimane sesquiterpenoids, fudecadione A and fudecadione B (1, 2), together with the known brefeldin A (3) and fulvic acid (4), were isolated from the soil fungus Penicillium sp. BCC 17468. Chemical structures were determined based on spectroscopic evidence including 1D and 2D NMR and mass spectral data. The proposed relative stereochemistry of fudecadiones A and B was based upon NOESY spectral data and chemical means. Compounds 1 and 4 exhibited anticancer activity against MCF-7, KB, and NCI-H187, with IC (50) values in the range of 5.05-45.43 µg/mL, while compound 2 was inactive against these tumor cells. Brefeldin (3) also displayed antimalarial activity against PLASMODIUM FALCIPARUM (K1, multidrug-resistant strain), with an IC (50) value of 1.12 µg/mL.