Received 4 April 2011
The asymmetric unit of the title compound, C19H12O5, contains two independent molecules, both slightly buckled along an axis passing through the C=O bonds of the anthraquinone ring system (r.m.s. deviation of non-H atoms = 0.082 and 0.148 Å): the benzene rings are twisted to each other by 4.3 (3)°in one molecule and 10.6(3)° in the other. In both molecules, the hydroxy group forms an intramolecular O-HO hydrogen bond. The two independent molecules interact by - stacking with a centroid-centroid distance of 3.539 (2) Å between hydroxybenzene rings of adjacent molecules.
Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU5188 ).
We thank the University of Malaya for supporting this study.
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