Diethyl 1,2-cyclopropanedicarboxylate, trans-1,2-diethoxycarbonyl-cyclopropane, diethyl cis-1,2-cyclopropanedicarboxylate, cyclopropane-1,2-dicarboxylic acid diethyl ester, Diethyl trans-cyclopropane-1,2-dicarboxylate, 1,2-Cyclopropanedicarboxylic acid,diethyl ester, diethyl trans-1,2-cyclopropanedicarboxylate