10-Hydroxy-10-(1,3-thiazol-2-ylmethyl)phenanthren-9(10H)-one

In the title phenanthrenone compound, C18H13NO2S, the dihydrophenanthrene ring system is not planar, with its central ring distorted to a screw-boat conformation. The essentially planar thiazole ring [maximum deviation = 0.005 (1) Å] is inclined at an interplanar angle of 23.36 (5)° with respect to the mean plane through the dihydrophenanthrene ring system. In the crystal packing, intermolecular O—H⋯N hydrogen bonds link the molecules into infinite chains along the a axis. Weak intermolecular C—H⋯π interactions further stabilize the crystal packing.

In the title phenanthrenone compound, C 18 H 13 NO 2 S, the dihydrophenanthrene ring system is not planar, with its central ring distorted to a screw-boat conformation. The essentially planar thiazole ring [maximum deviation = 0.005 (1) Å ] is inclined at an interplanar angle of 23.36 (5) with respect to the mean plane through the dihydrophenanthrene ring system. In the crystal packing, intermolecular O-HÁ Á ÁN hydrogen bonds link the molecules into infinite chains along the a axis. Weak intermolecular C-HÁ Á Á interactions further stabilize the crystal packing.

Comment
Research interest in phenanthrenequinone can be traced back as early as 1905 (Bloom, 1961;Meyer & Spengler, 1905).
Phenanthrenequinone and its derivatives possess a wide range of activities, especially biological and pharmaceutical. For example, phenanthrenequinone is one of the major quinones in diesel exhaust particles (Milko & Roithova, 2009), which plays a negative role in inducing pathogenic processes such as lung cancer (Schuetzle et al., 1981), allergies (McClellan, 1987) or asthma (Nel et al., 2001). Phenanthrenequinone has also been reported to be a good substrate for microsomal NADPHcytochrome P450 reductase and that superoxide and hydroxyl radicals generated during redox cycling of the quinone by this flavin enzyme mainly participate in the DEP-prompted oxidative stress (Shimada et al., 2004;Kumagai et al., 1997).
The photochemistry of phenanthrenequinone has been investigated early in 1956 (Mustafa et al., 1956). In recent years, more complex products have been obtained in photoreactions of oxazoles with phenanthrenequinone (Zhang et al., 2004).

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.