1,4-Dimethyl-7-oxabicyclo(2.2.1)heptane-2,3-dicarboxylic acid (endo,endo)- 109282-37-3 7-Oxabicyclo(2.2.1)heptane-2,3-dicarboxylic acid, 1,4-dimethyl-, (endo,endo)-