Alogliptin [INN]; 1,3-Isobenzofurandione; 2-Benzofuran-1,3-dione; 1,3-Dioxophthalan

Phthalic anhydride appears as a colorless to white lustrous solid in the form of needles with a mild distinctive odor. Moderately toxic by inhalation or ingestion and a skin irritant. Melting point 64°F Flash point 305°F. Forms a corrosive solution when mixed with water. Used in the manufacture of materials such as artificial resins. Phthalic anhydride is the cyclic dicarboxylic anhydride that is the anhydride of phthalic acid. It has a role as an allergen. It is a cyclic dicarboxylic anhydride and a member of 2-benzofurans.

Phthalic anhydride is a key organic chemical raw material, serving as a critical intermediate in the production of phthalate plasticizers, coatings, saccharin, dyes, and other organic compounds.