New sesquiterpenes, JBIR-27 and -28, isolated from a tunicate-derived fungus, Penicillium sp. SS080624SCf1

In the course of our screening program for novel metabolites from tunicate-derived fungi, novel sesquiterpenoids, named JBIR-27 ( 1 ) and -28 ( 2 ), together with known sporogen-AO1 and phomenone, were isolated from the culture broth of Penicillium sp. SS080624SCf1. The structures of 1 and 2 were determined to be eremophilane analogs on the basis of extensive NMR and MS analyses. Sporogen-AO1, phomenone and 2 showed cytotoxicity against human cervical carcinoma cell line HeLa at IC 50 values of 8.3, 19 and 92 μ M , respectively, whereas 1 was inactive at a concentration of 80 μ M .