7-Hydroxy-8-isopropyl-1,1,4a-trimethyl-4a,9,10,10a-tetrahydro-phenanthren-2(1H)-one

Abstract

The title compound, C20H26O2, was isolated from a chloro­form extract of Tetra­clinis articulata wood. The mol­ecule contains three fused rings which exhibit different conformations. The non-aromatic oxo-substituted ring has a screw-boat conformation, while the central ring has a half-chair conformation. In the crystal, mol­ecules are linked to each other by inter­molecular O—H⋯O hydrogen bonds involving the carbonyl and hy­droxy groups.

Crystal structure of (4bS,8aR)-1-isopropyl-4b,8,8-trimethyl-7-oxo-4b,7,8,8a,9,10-hexahydrophenanthren-2-yl acetate

“…These include several compounds similar to the title compound. One with a similar conformation has a hydroxyl substituent in place of the acetate in the title compound (Benharref et al, 2011), and three others have a methoxy group in position 4b and carbaldehyde/benzenesulfonohydrazide (Vo et al, 2008) or biphenylsulfonyl (Gu & You, 2011) in position 9 ( Fig. 4b), while six entries (Oubabi et al, 2014a,b;Zeroual et al, 2007Zeroual et al, , 2008Cutfield et al, 1974;Pettit et al, 2004) have 1-isopropyl-4b,8,8-trimethyl substituents ( Fig.…”