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