The crystal structures of two new coumarin derivatives: 2-(4-{2-[(2-oxo-2H-chromen-4-yl)-oxy]acet-yl}piperazin-1-yl)acetamide and N-(2,4-di-meth-oxy-benz-yl)-2-[(2-oxo-2H-chromen-4-yl)-oxy]acetamide

Crystal structure and Hirshfeld surface analysis of 2-[(2-oxo-2H-chromen-4-yl)-oxy]acetic acid dimethyl sulfoxide monosolvate

The title compound, C11H8O5·(CH3)2SO, is a new coumarin derivative. The asymmetric unit contains two coumarin mol-ecules (A and B) and two di-methyl-sulfoxide solvent mol-ecules (A and B). The dihedral angle between the pyran and benzene rings in the chromene moiety is 3.56 (2)° for mol-ecule A and 1.83 (2)° for mol-ecule B. In mol-ecule A, the dimethyl sulfoxide sulfur atom is disordered over two positions with a refined occupancy ratio of 0.782 (5):0.218 (5). In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, forming chains running along the c-axis direction. The chains are linked by C-H⋯O hydrogen bonds, forming layers parallel to the ac plane. In addition, there are also C-H⋯π and π-π inter-actions present within the layers. The inter-molecular contacts in the crystal have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots, which indicate that the most important contributions to the packing are from H⋯H (33.9%) and O⋯H/H⋯O (41.2%) contacts.