Figure 1 The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) x, -1+y, z; (ii) 1-x, -1/2+y, 1/2-z; (iii) 1-x, 2-y, 1-z; (iv) 2-x, 1-y, 1-z; (v) x, 1+y, z.]  [article HTML]