Constituents of Eupomatia species. VI. The structures of eupodienone-1, -2 and -3

Abstract

Eupodienone-1, from the bark of Eupomatia laurina, has been shown by spectroscopic and degradative studies to have the novel neolignan structure (2), (7R,8S,9R)-9-acetoxy-2,3,3',4,5'-pentamethoxy-7,8- dimethyl-6,7,8,9-tetrahydrospiro[5H-benzocycloheptene-5,1'-cyclohexa- 2',5'-dien]-4'-one. Eupodienone-2 is the corresponding 9-hydroxy derivative (3) and eupodienone-3, the 9-benzoyloxy derivative (4). The substance EL3 is the 9-ethoxy derivative (5), an artefact.