STRUCTURAL ELUCIDATION OF TRICHOTETRONINES - POLYKETIDES POSSESSING ABICYCLO[2.2.2]OCTANE SKELETON WITH A TETRONIC ACID MOIETY ISOLATED FROM TRICHODERMA SP

The isolation and structural elucidation of two novel fungal metabolit es, trichotetronine and its dihydro congener, from Trichoderma sp. are described. The structures, including the relative and absolute stereo chemistry, have been established using a variety of data including ext ensive NMR analyses and CD spectral studies. The compounds possess a b icyclo[2.2.2]octene system in conjunction with a tetronic acid moiety and two conjugated ketonic side chains. Along with them, trichodimerol , a known compound possessing an axis of symmetry, has been isolated. Both trichodimerol and the newly isolated trichotetronines appear to b e derived from the condensation of two hexaketides having two extra me thyl groups.