1,4,5,8-Naphthalenetetracarboxylic 1,8:4,5-dianhydride 1,4,5,8-Naphthalenetetracarboxylic acid anhydride 1,4,5,8-Naphthalenetetracarboxylic acid dianhydride 1,4,5,8-Naphthalenetetracarboxylic dianhydride 1,8:4,5-Naphthalenetetracarboxylic dianhydride 2,7-Dioxapyrene-1,3,6,8-tetrone 81-30-1 NSC84241 Naphthalenetetracarboxylic dianhydride [2]Benzopyrano[6,5,4-def][2]benzopyran-1,3,6,8-tetrone