1,2-cyclohexanedicarboxylic acid 2305-32-0 InChI=1/C8H12O4/c9-7(10)5-3-1-2-4-6(5)8(11)12/h5-6H,1-4H2,(H,9,10)(H,11,12 cyclohexane-1,2-dicarboxylic acid