“…19 The structures of 3 and 4 were identified by NMR as patagonic acid 14 and (4aR,5S,6R,8aR)-5-[2-(2,5-dihydro-5-methoxy-2-oxofuran-3-yl)ethyl]-3,4,4a,5,6,7,8,8a-octahydro-5,6,8a-trimethylnaphthalene-1-carboxylic acid, respectively, both diterpenes of the clerodane type. 15,24,25 According to the literature 14 on substance 3 the chemical shifts of C-2 is 27.4 and C-7 is 27.2. HMBC spectrum showed a correlation of the signal at 0.85 (d, J 6.7 Hz, CH 3 -17) with the signal at 27.2, being this signal assigned to C-7, and a correlation of the signal at 6.81 (br s H-3) with the signal at 27.4, which was assigned to C-2.…”