A new highly transformed sorbicillinoid derivative, trichoreesin A (1), and four known monomeric sorbicillinoids, sorbicillin (2), 2',3'-dihydrosorbicillin (3), 3-demethylsorbicillin (4), and sohirnone A (5), were discovered from Trichoderma reesei Z56-8, an epiphyte from the marine brown alga Sargassum sp. The structure and relative configuration of 1 were determined by interpretation of UV, IR, NMR, and MS signals, and its absolute configuration was assigned by analysis of ECD data aided by quantum chemical calculations. This is the first survey of metabolites from marine algicolous T. reesei. Compound 1 represents the first bicyclic vertinolide derivative, and it possesses inhibition of several marine phytoplankton species.
Keywords: Trichoderma; sorbicillinoid; trichoreesin; vertinolide.