3,6-Endooxyphthalic anhydride, hexahydro- 3,6-Endoxohexahydrophthalic anhydride 4,7-Epoxyisobenzofuran-1,3-dione, hexahydro- 5442-12-6 7-Oxabicyclo(2.2.1)heptane-2,3-dicarboxylic anhydride NSC 14003 Norcantharidin Phthalic anhydride, hexahydro-3,6-endoxo-