Crystal structure and Hirshfeld surface analysis of 3,4-dihydro-2-(2,4-dioxo-6-methylpyran-3-ylidene)-4-(4-pyridin-4-yl)-1,5-benzodiazepine.

The title compound, C20H17N3O3 [systematic name: 2-(6-methyl-2,4-dioxo-pyran-3-yl-idene)-4-(pyridin-4-yl)-2,3,4,5-tetra-hydro-1H-1,5-benzodiazepine], is built up from a benzodiazepine ring system linked to pyridyl and pendant di-hydro-pyran rings, where the benzene and pyridyl rings are oriented at a dihedral angle of 43.36 (6)°. The pendant di-hydro-pyran ring is rotationally disordered in a 90.899 (3):0.101 (3) ratio with the orientation of each component largely determined by intra-molecular N-HDiazp⋯ODhydp (Diazp = diazepine and Dhydp = di-hydro-pyran) hydrogen bonds. In the crystal, mol-ecules are linked via pairs of weak inter-molecular N-HDiazp⋯ODhydp hydrogen bonds, forming inversion-related dimers with R 2 2(26) ring motifs. The dimers are further connected along the b-axis direction by π-π stacking inter-actions between the pendant di-hydro-pyran and pyridyl rings with centroid-centroid distances of 3.833 (3) Å and a dihedral angle of 14.51 (2)°. Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (50.1%), H⋯C/C⋯H (17.7%), H⋯O/O⋯H (16.8%), C⋯C (7.7%) and H⋯N/N⋯H (5.3%) inter-actions. Hydrogen-bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing.