3′,6′-Bis(diethylamino)-2-[(E)-2-(4-hydroxy-3-methoxybenzylideneamino)ethyl]spiro[isoindoline-1,9′-xanthen]-3-one ethanol monosolvate

In the title compound, C38H42N4O4·C2H6O, prepared via a spirolactam ring-formation reaction in a rhodamine dye, the xanthene ring system is approximately planar (r.m.s. deviation = 0.0014Å) and subtends dihedral angles of 88.10 (3) and 86.92 (4)° with the spirolactam (r.m.s. deviations = 0.0012 Å) and benzene rings, respectively. The crystal structure consists of chains parallel to [-101], formed via O—H...O interactions.