Crystal structures and Hirshfeld surface analyses of (E)-N'-benzyl-idene-2-oxo-2H-chromene-3-carbo-hydrazide and the disordered hemi-DMSO solvate of (E)-2-oxo-N'-(3,4,5-trimeth-oxybenzyl-idene)-2H-chromene-3-carbohydrazide: lattice energy and inter-molecular inter-action energy calculations for the former.

The crystal structures of the disordered hemi-DMSO solvate of (E)-2-oxo-N'-(3,4,5-tri-meth-oxy-benzyl-idene)-2H-chromene-3-carbohydrazide, C(20)H(18)N(2)O(6)·0.5C(2)H(6)OS, and (E)-N'-benzyl-idene-2-oxo-2H-chromene-3-carbohydrazide, C(17)H(12)N(2)O(3) (4: R = C(6)H(5)), are discussed. The non-hydrogen atoms in compound [4: R = (3,4,5-MeO)(3)C(6)H(2))] exhibit a distinct curvature, while those in compound, (4: R = C(6)H(5)), are essential coplanar. In (4: R = C(6)H(5)), C-H⋯O and π-π intra-molecular inter-actions combine to form a three-dimensional array. A three-dimensional array is also found for the hemi-DMSO solvate of [4: R = (3,4,5-MeO)(3)C(6)H(2)], in which the mol-ecules of coumarin are linked by C-H⋯O and C-H⋯π inter-actions, and form tubes into which the DMSO mol-ecules are cocooned. Hirshfeld surface analyses of both compounds are reported, as are the lattice energy and inter-molecular inter-action energy calculations of compound (4: R = C(6)H(5)).