Crystal structure of N0-[(1E)-1-(6-methyl- 2,4-dioxo-3,4-dihydro-2H-pyran-3-yl- idene)ethyl]benzenesulfonohydrazide

In the title compound, C14H14N2O5S, the molecule exists in the enamine (C C—NH) tautomeric form. The hydrazone fragment derived from the 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one moiety is approximately planar, with a maximum deviation of 0.1291 (11) A ̊ for the N atom bound to the S atom of the benzensulfonohydrazide group. The latter adopts a gauche conformation relative to the hydrazone N—N bond, with an N—N—S angle of 113.54 (10). There is an intra-molecular N—H O C hydrogen bond that stabilizes the tautomeric form. In the crystal, molecules are linked by N— H O C hydrogen bonds into chains extending parallel to [100]