1,2-cyclopentanedicarboxylic acid, 4-oxo-, dimethyl ester, (1S,2S)- InChI=1/C9H12O5/c1-13-8(11)6-3-5(10)4-7(6)9(12)14-2/h6-7H,3-4H2,1-2H3/t6-,7-/m0/s dimethyl (1S,2S)-4-oxocyclopentane-1,2-dicarboxylate