InChI=1S/C20H20Cl2O4/c1-13(2)6-5-11-25-19(23)14-7-3-8-15(12-14)20(24)26-17-10-4-9-16(21)18(17)22/h3-4,7-10,12-13H,5-6,11H2,1-2H3