Received 7 May 2013
In the title compound, C26H22N2O5, the system consisting of five fused rings, being essentially planar with an r.m.s. deviation from the least-squares plane of 0.049 (3) Å, makes a dihedral angle of 58.72 (12)° with the plane of the ethyl carboxylate group immediately attached to it, and a dihedral angle of 89.48 (14)° with the plane of the ethyl carboxylate group attached via the -CH2- bridge. Bond lengths indicate -delocalization over the whole pentacyclic system. The molecular conformation is stabilized by a weak intramolecular C-HO hydrogen bond. In the crystal, molecules form stacks along the b-axis direction, neighboring molecules within each stack being related by inversion and the shortest distance between the centroids of the pyridine rings within the stack being 3.667 (2) Å.
For pharmaceutical properties of indolizines and related compounds, see: Olden et al. (1991); Jaffrezou et al. (1992). For the preparation of annulated indolizine, see: Liu et al. (2010). For standard bond-length data, see: Allen et al. (1987).
Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: YK2094 ).
The authors acknowledge financial support by 2012JSSPITP3193. This work was also sponsored by the research funds of Xuzhou City (XZZD1213 and XF10C015).
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