30627-50-0 5-18-07-00033 (Beilstein Handbook Reference) 7-Oxabicyclo(2.2.1)heptane-2,3-dicarboxylic acid, benzyl ester, exo-(Z)- BRN 3983205 exo-cis-7-Oxabicyclo(2.2.1)heptane-2,3-dicarboxylic acid benzyl ester