SYNTHETIC STUDIES ON WORTMANNIN AND 11-DESACETOXYWORTMANNIN

This report describes the first synthesis of the highly reactive furanocyclohexadienone lactone subunit of the natural products wortmannin (1) and 11-desacetoxywortmannin (2). The simplified wortmannin analogue 6 was prepared by acid treatment of aminomethylene lactone 22 in analogy to the known conversion of lactone 3 into wortmannin. Compound 22 was, in turn, prepared from the readily accessible lactone 18 through sequential oxidations and introduction of the aminomethylene unit using tris(dimethylamino)methane.