Constituents of Endiandra species. IV. Isolation of 2-(8'-[(E,E)-5'-phenylpenta-2',4''-dien-1''-yl]bicyclo[4,2,0]octa-2',4'-dien-7'-yl)acetic acid, a biogenetically predicted metabolite of Endiandra introrsa (Lauraceae) and its structure determination by means of 1D and 2D N.M.R. spectroscopy

The structure (6a) is proposed for the title compound, on the basis of chemical and spectroscopic data. In particular, a combination of one- and two-dimensional n.m.r. techniques has led to this assignment. Compound (6a) is relatively unstable and its isolation requires a careful extraction process.