Diketopiperazines and phthalides from a marine derived fungus of the order pleosporales

Five metabolites, (Z)-6-benzylidene-3-hydroxy-m ethyl-1,4-dimethyl-3-methyl sulfanyl pi perazine-2,5-dione (1), (3S,3'R)-3-(3'-hydroxybutyl)-7-methoxyphthalide (2), (S)-3-butyl-7-methoxyphthalide (3), (3R,6R)-bisdethiodi(methylthio)hyalodendrin (4), and bis-N-norgliovictin (5), were isolated from the culture broth of the marine derived fungus of the order Pleosporales strain CRIF2. Compounds 1 and 2 are new fungal metabolites, while 3 was isolated for the first time as a natural product. Compounds 1, 3, and 4 exhibited only weak cytotoxic activity, while 5 was inactive at 50 mu g/mL.