Date Published: April 01, 2011
Publisher: International Union of Crystallography
Author(s): Madeleine Helliwell, Despina A. Nasiopoulou, Philip A. Harris, Antigoni Kotali, John A. Joule.
The title compound, C16H12N2O4S, was obtained by the condensation of 3-acetyl-4-hydroxycoumarin with thien-2-ylcarbonyl hydrazide. The pyran ring adopts a 2,4-dione tautomeric form. The benzopyran ring system is almost coplanar with the thiophene ring [dihedral angle 0.9 (2)°]. The exocyclic C=C double bond has an E geometry. The molecular conformation is stabilized by an intramolecular N—H⋯O hydrogen bond. In the crystal, intermolecular N—H⋯O hydrogen bonds link the molecules into chains along the a axis.
For the synthesis, characterization and reactions of N-acyl hydrazones, see: Kotali (2009 ▶); Kotali et al., (2010 ▶).