An azo dye mol­ecule having a pyridine‐2,6‐dione backbone

The title azo dye, 2‐(2‐methoxy­ethoxy)ethyl 4‐(5‐cyano‐1‐ethyl‐4‐methyl‐2,6‐dioxo‐1,2,3,6‐tetra­hydro­pyridin‐3‐ylidene)hydrazino]benzoate, C₂₁H₂₄N₄O₆, with a 1‐ethyl‐5‐cyano‐2‐hydr­oxy‐4‐methyl‐6‐pyridone component, crystallizes in the hydrazone form. Hydrogen bonding mediates the formation of four‐mol­ecule aggregates, which are further grouped into an extended structure by π–π stacking inter­actions between the aromatic rings of adjacent mol­ecules, with a centroid–centroid separation of 3.697 (2) Å.