Phthalimide
Phthal"i*mide\, n. [Phthalic + imide.] (Chem.) An imido derivative of phthalic acid, obtained as a white crystalline substance, C6H4.(CO)2NH, which has itself (like succinimide) acid properties, and forms a series of salts. Cf. Imido acid, under Imido.