New brasiliamide congeners, brasiliamides C, D and E, from Penicillium brasilianum Batista JV-379

Three new brasiliamide congeners, brasiliamides C, D and E, were isolated from okara fermented with Penicillium brasilianum Batista JV-379. Their structures were elucidated on the basis of spectral data and chemical evidence. NMR spectra of these brasiliamides exhibited a mixture of four or two conformers due to the restricted rotation of an amide bond in a solution. The (1)H- and (13)C-NMR spectral data were analyzed for a major rotamer at an appropriate temperature, since the signals were broadened at room temperature. Both brasiliamides C and D showed convulsive activity against silkworms with an ED(50) value of 400 microg/g of diet, whereas brasiliamide E showed less activity than the others.