2-{[2-(1-Methyl-2,2-dioxo-3,4-dihydro-1H-2λ⁶,1-benzothia­zin-4-yl­idene)hydrazin-1-yl­idene]meth­yl}phenol

In the title compound, C₁₆H₁₅N₃O₃S, the dihedral angle between the aromatic rings is 8.18 (11)° and the C=N—N=C torsion angle is 178.59 (14)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.8157 (18) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.045 Å). An intra­molecular O—H...N hydrogen bond closes an S(6) ring. In the crystal, weak C—H...O inter­actions link the mol­ecules, with all three O atoms acting as acceptors.