Abstract
The asymmetric unit of the title compound, C17H14O6S, contains four crystallographically independent molecules in which the pyranone units are essentially planar, with maximum deviations of 0.016 (2), 0.019 (2), 0.025 (2), 0.014 (2), 0.020 (2), 0.010 (2), 0.003 (2) and 0.012 (2) angstrom. One of the thiophene rings is disordered over two positions, with an occupancy ratio of 0.739 (4):0.261 (4). The dihedral angles between the two pyranone rings in the independent molecules are 59.42 (8), 48.67 (8), 60.62 (9) and 51.60 (8)degrees. In the crystal, molecules are linked through intermolecular O-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonds, forming a three-dimensional network.