(Z)-6-{[1,3-Dihydroxy-2-(hydroxymethyl)propan-2-ylamino]methylene}-2-methoxy-4-[(E)-o-tolyldiazenyl]cyclohexa-2,4-dienone

Abstract

The title compound, C<inf>19</inf>H<inf>23</inf>N<inf>3</inf>O<inf>5</inf>, adopts the keto-amine tautomeric form with the hydroxy H atom located on the N atom, where it is involved in a strong intramolecular N-H⋯O hydrogen bond. The compound exhibits trans geometry with respect to the azo N=N double bond, with a dihedral angle between the two benzene rings of 38.03 (6)°. The packing of the molecules in the crystal structure is determined by O-H⋯O and C-H⋯O hydrogen bonds. A comparison with closely related compounds is given. © 2006 International Union of Crystallography.