18188-89-1 2-Phthalimidotropone 5-21-10-00405 (Beilstein Handbook Reference) BRN 1534331 N-(7-Oxo-1,3,5-cycloheptatrien-1-yl)phthalimide Phthalimide, N-(7-oxo-1,3,5-cycloheptatrien-1-yl)-