Received 27 February 2013
In the title compound, C20H16N2O2, the condensed tricyclic fragment is near to planar, with an r.m.s. deviation of 0.0531 Å. The 1,4-dihydropyridine (1,4-DHP) ring adopts a slightly puckered boat-like conformation. The N and opposite C atoms deviate from the least-squares plane of the four other ring atoms by 0.039 (3) and 0.141 (3) Å, respectively. The C=O group located at the tricyclic fragment is fixed in an s-trans orientation, while the second C=O group adopts an s-cis orientation with respect to the double bonds of the 1,4-DHP ring. The pyridine ring has a pseudo-axial orientation with respect to the 1,4-DHP ring. The dihedral angle between the tricyclic system and the pyridine ring is 77.3 (3)°. In the crystal, the pyridine N atom accepts a hydrogen bond from the N-H group of the 1,4-DHP ring. The hydrogen bonds link the molecules into infinite C(8) chains along the b-axis direction.
For general information on the relationship between 1,4-dihydropyridine ring substituents and pharmaceutical effects, see: Christopher et al. (2010); Bisenieks et al. (1987, 1995); Ivanov et al. (1989). For the synthesis of 1,4-DHP-containing tricyclic derivatives, see: Bisenieks et al. (1982).
Data collection: COLLECT (Hooft, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FY2091 ).
The study was supported by the Latvian National Research Programme 2010-2013: "Development of prevention, treatment, diagnostic means, practices and biomedicine technologies for improvement of public health".
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