Crystal structure of 7β-hy-droxy-royleanone isolated from Taxodium ascendens (B.)

The title compound, C H O [systematic name: (4b ,8a ,10 )-3,10-dihy-droxy-2-isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a,9,10-octa-hydro-phenanthrene-1,4-dione], is an abietane-type diterpene, which was isolated from (B.). The compound crystallizes in the chiral space group 2 , but it was not possible to determine the absolute structure of the mol-ecule in the crystal by resonant scattering. The mol-ecular structure is stabilized by two intra-molecular O-H⋯O hydrogen bonds, enclosing (5) and (6) ring motifs. In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds, forming chains along the [010] direction. The crystal structure of the 10 stereoisomer of the title compound, isolated from the roots of (Verbenaceae), has been reported. It crystallized in the chiral space group 2 2 2 , and the absolute structure was determined as (4b ,8a ,10 ), by resonant scattering using Cu α radiation [Razak (2010 ▸). E , o1566-o1567].