InChI=1S/C21H22O6/c1-12-15-7-13(5-4-6-22)8-16(23-2)20(15)27-19(12)14-9-17(24-3)21-18(10-14)25-11-26-21/h4-5,7-10,12,19,22H,6,11H2,1-3H3/b5-4+