Structure of hopeaphenol: X-ray analysis of the benzene solvate of dibromodeca-O-methylhopeaphenol
The X-ray crystal structure analysis of the dibromo-derivative of deca-O-methylhopeaphenol has established the structure and absolute configuration of hopeaphenol, a heartwood extractive of Hopea odorata. The crystals are monoclinic, of space group C2, with four units of C66H60Br2O12,2C6H6 in the unit cell of dimensions a= 21·75, b= 11·31, c= 27·78 Å, β= 95° 25′. Phase determination was based initially on the two bromine atoms, and subsequent electron-density calculations revealed the non-hydrogen atoms. The atomic parameters were refined by least-squares methods, and the final R over 4688 independent observed reflexions was 11·9%.