Crystal structure and Hirshfeld surface analysis of 2,6-bis[4-(ethoxycarbonyl)-5-methylpyrazol-1-yl]pyridine

The title compound (systematic name: ethyl 1-{6-[4-(ethoxycarbonyl)-5-methylpyrazol-1-yl]pyridin-2-yl}-5-methylpyrazole-4-carboxylate), C 19 H 21 N 5 O 4 , consists of a central pyridine ring substituted by two functionalized pyrazole rings and crystallizes in the centrosymmetric space group C 2/ c . The pyridine–pyrazole and pyrazole–pyrazole dihedral angles are 30.55 (5) and 50.81 (8)°, respectively, indicating significant deviations from coplanarity. An intramolecular C—H...O hydrogen bond stabilizes the molecular conformation. In the crystal, molecules form columns along the c -axis, but large centroid separations and offsets between parallel pyridine rings contribute to the absence of π–π stacking. Intermolecular C—H...N and C—H...O hydrogen bonds link molecules into a three-dimensional network. Hirshfeld surface analysis shows that H...H contacts dominate the packing (49.9%), with hydrogen-involving interactions contributing over 90% of all contacts. The molecular shape is moderately anisotropic, with globularity and asphericity values of 0.677 and 0.395, respectively. These results highlight the key role of hydrogen-based interactions in directing the supramolecular organization and crystal cohesion.