Novel fungal metabolites, demethylsorbicillin and oxosorbicillinol, isolated from Trichoderma sp USF-2690

The novel compounds, demethylsorbicillin (1) and oxosorbicillinol (2), were isolated from a fermentation broth of Trichoderma sp, USF-2690. The structures of these compounds, which were determined from spectroscopic evidence, suggest the possibility: that methylation at C-6 and oxidation at C-1 and C-6 of sorbicillin were controlled in the early polyketide stage before the formation of oxidized sorbicillin dimers. In a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay, 2 gave an ED50 value of 87.7 mu M.