Zhou, LinTimmermann, Barbara N.Grittini, CarinaBruck, Michael A.Enemark, John H.2015-05-042015-05-041996Zhou, L., Timmermann, B.N., Grittini, C., Bruck, M.A., and Enemark, J.H. "Tarapacol 15-Acetate, a New Diterpenoid from Grindelia tarapacana Phil." Acta Cryst. (1996). C52, 1042-1044 http://dx.doi.org/10.1107/S0108270195013473https://hdl.handle.net/1808/17565In the title compound, 15-acetoxy-14(S)-hydroxy-13-epi-manoyl oxide {IUPAC systematic name: 2-(dodecahydro-3,4a,7,7,10a-pentamethyl-1H-naphtho[2,1-b]pyran-3-yl)-2-hydroxyethyl acetate}, C22H38N4, rings A and B have chair conformations. Ring C adopts a boat conformation with the 16-methyl group in an axial position and the bulky glycol monoacetate group in an equatorial position. Ring systems A/B and B/C (conventional IUPAC labdane diterpenoid nomenclature) are trans fused about the C(5)-C(10) and C(8)-C(9) bonds, respectively. The present study establishes the relative stereochemistry at the C(14) position.Article10.1107/S0108270195013473openAccess