3-(6-Fluoro-4-oxo-4H-chromen-3-yl)-3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dione

In the title compound, C16H11FN2O4S, the mean planes of the bicyclic chromone system and of the benzene ring of the benzothiadiazine derivative make a dihedral angle of 54.28 (5)°. An intramolecular N—H⋯O hydrogen bond occurs. In the crystal, molecules are linked into layers by N—H⋯O and C—H⋯O hydrogen bonds, generating an infinite two-dimensional network.

In the title compound, C 16 H 11 FN 2 O 4 S, the mean planes of the bicyclic chromone system and of the benzene ring of the benzothiadiazine derivative make a dihedral angle of 54.28 (5) . An intramolecular N-HÁ Á ÁO hydrogen bond occurs. In the crystal, molecules are linked into layers by N-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds, generating an infinite two-dimensional network.
In the molecule of the title compound ( Fig. 1), the two rings of the chromone system (F1, O1, O4, C2-C10) are coplanar, making a dihedral angle of 0.55 (19)°. The carbon atom C11 deviates only by 0.034 (5) Å from the mean plane of the chromone. The phenyl ring (C12-C17) and the atoms N4, S1 and C11 are coplanar as well (rms deviation = 0.033) and make a dihedral angle of 54.28 (5)° with the mean plane of the chromone system.
The crystal structure is stabilized by intra-and intermolecular N-H···O and C-H···O hydrogen bonds which link the molecules into an infinite two-dimensional network (Fig. 2).

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.